compat with mypy 1.14 (#48626)

* OSError.errno apparently is int | None, but already part of __str__ anyway so drop

* fix disambiguate_spec_from_hashes

* List[Spec].sort() complains, ignore it

* fix typing of KnownCompiler, and use it in asp.py

.github/workflows/coverage.yml

@@ -29,7 +29,7 @@ jobs:
     - run: coverage xml
 
     - name: "Upload coverage report to CodeCov"
-      uses: codecov/codecov-action@05f5a9cfad807516dbbef9929c4a42df3eb78766
+      uses: codecov/codecov-action@1e68e06f1dbfde0e4cefc87efeba9e4643565303
       with:
         verbose: true
         fail_ci_if_error: false

.github/workflows/requirements/style/requirements.txt

@@ -2,6 +2,6 @@ black==24.10.0
 clingo==5.7.1
 flake8==7.1.1
 isort==5.13.2
-mypy==1.8.0
+mypy==1.11.2
 types-six==1.17.0.20241205
 vermin==1.6.0

.github/workflows/valid-style.yml

@@ -20,7 +20,7 @@ jobs:
     - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
     - uses: actions/setup-python@0b93645e9fea7318ecaed2b359559ac225c90a2b
       with:
-        python-version: '3.11'
+        python-version: '3.13'
         cache: 'pip'
     - name: Install Python Packages
       run: |
@@ -39,7 +39,7 @@ jobs:
         fetch-depth: 0
     - uses: actions/setup-python@0b93645e9fea7318ecaed2b359559ac225c90a2b
       with:
-        python-version: '3.11'
+        python-version: '3.13'
         cache: 'pip'
     - name: Install Python packages
       run: |
@@ -58,7 +58,7 @@ jobs:
     secrets: inherit
     with:
       with_coverage: ${{ inputs.with_coverage }}
-      python_version: '3.11'
+      python_version: '3.13'
   # Check that spack can bootstrap the development environment on Python 3.6 - RHEL8
   bootstrap-dev-rhel8:
     runs-on: ubuntu-latest

lib/spack/docs/config_yaml.rst

@@ -25,14 +25,23 @@ These settings can be overridden in ``etc/spack/config.yaml`` or
 The location where Spack will install packages and their dependencies.
 Default is ``$spack/opt/spack``.
 
----------------------------------------------------
-``install_hash_length`` and ``install_path_scheme``
----------------------------------------------------
+---------------
+``projections``
+---------------
 
-The default Spack installation path can be very long and can create problems
-for scripts with hardcoded shebangs. Additionally, when using the Intel
-compiler, and if there is also a long list of dependencies, the compiler may
-segfault. If you see the following:
+.. warning::
+
+   Modifying projections of the install tree is strongly discouraged.
+
+By default Spack installs all packages into a unique directory relative to the install
+tree root with the following layout:
+
+.. code-block::
+
+   {architecture}/{compiler.name}-{compiler.version}/{name}-{version}-{hash}
+
+In very rare cases, it may be necessary to reduce the length of this path. For example,
+very old versions of the Intel compiler are known to segfault when input paths are too long:
 
      .. code-block:: console
 
@@ -40,36 +49,25 @@ segfault. If you see the following:
        ** Segmentation violation signal raised. **
        Access violation or stack overflow. Please contact Intel Support for assistance.
 
-it may be because variables containing dependency specs may be too long. There
-are two parameters to help with long path names. Firstly, the
-``install_hash_length`` parameter can set the length of the hash in the
-installation path from 1 to 32. The default path uses the full 32 characters.
+Another case is Python and R packages with many runtime dependencies, which can result
+in very large ``PYTHONPATH`` and ``R_LIBS`` environment variables. This can cause the
+``execve`` system call to fail with ``E2BIG``, preventing processes from starting.
 
-Secondly, it is also possible to modify the entire installation
-scheme. By default Spack uses
-``{architecture}/{compiler.name}-{compiler.version}/{name}-{version}-{hash}``
-where the tokens that are available for use in this directive are the
-same as those understood by the :meth:`~spack.spec.Spec.format`
-method. Using this parameter it is possible to use a different package
-layout or reduce the depth of the installation paths. For example
+For this reason, Spack allows users to modify the installation layout through custom
+projections. For example
 
      .. code-block:: yaml
 
        config:
-         install_path_scheme: '{name}/{version}/{hash:7}'
+         install_tree:
+           root: $spack/opt/spack
+           projections:
+             all: "{name}/{version}/{hash:16}"
 
-would install packages into sub-directories using only the package
-name, version and a hash length of 7 characters.
+would install packages into sub-directories using only the package name, version and a
+hash length of 16 characters.
 
-When using either parameter to set the hash length it only affects the
-representation of the hash in the installation directory. You
-should be aware that the smaller the hash length the more likely
-naming conflicts will occur. These parameters are independent of those
-used to configure module names.
-
-.. warning:: Modifying the installation hash length or path scheme after
-   packages have been installed will prevent Spack from being
-   able to find the old installation directories.
+Notice that reducing the hash length increases the likelihood of hash collisions.
 
 --------------------
 ``build_stage``

lib/spack/docs/developer_guide.rst

@@ -543,10 +543,10 @@ With either interpreter you can run a single command:
 
 .. code-block:: console
 
-   $ spack python -c 'from spack.spec import Spec; Spec("python").concretized()'
+   $ spack python -c 'from spack.concretize import concretize_one; concretize_one("python")'
    ...
 
-   $ spack python -i ipython -c 'from spack.spec import Spec; Spec("python").concretized()'
+   $ spack python -i ipython -c 'from spack.concretize import concretize_one; concretize_one("python")'
    Out[1]: ...
 
 or a file:

lib/spack/docs/module_file_support.rst

@@ -456,14 +456,13 @@ For instance, the following config options,
        tcl:
          all:
            suffixes:
-             ^python@3: 'python{^python.version}'
+             ^python@3: 'python{^python.version.up_to_2}'
              ^openblas: 'openblas'
 
-will add a ``python-3.12.1`` version string to any packages compiled with
-Python matching the spec, ``python@3``. This is useful to know which
-version of Python a set of Python extensions is associated with. Likewise, the
-``openblas`` string is attached to any program that has openblas in the spec,
-most likely via the ``+blas`` variant specification.
+will add a ``python3.12`` to module names of packages compiled with Python 3.12, and similarly for
+all specs depending on ``python@3``. This is useful to know which version of Python a set of Python
+extensions is associated with. Likewise, the ``openblas`` string is attached to any program that
+has openblas in the spec, most likely via the ``+blas`` variant specification.
 
 The most heavyweight solution to module naming is to change the entire
 naming convention for module files. This uses the projections format

lib/spack/docs/requirements.txt

@@ -4,7 +4,7 @@ sphinx_design==0.6.1
 sphinx-rtd-theme==3.0.2
 python-levenshtein==0.26.1
 docutils==0.21.2
-pygments==2.18.0
+pygments==2.19.1
 urllib3==2.3.0
 pytest==8.3.4
 isort==5.13.2

lib/spack/llnl/util/filesystem.py

@@ -1740,8 +1740,7 @@ def find(
 
 
 def _log_file_access_issue(e: OSError, path: str) -> None:
-    errno_name = errno.errorcode.get(e.errno, "UNKNOWN")
-    tty.debug(f"find must skip {path}: {errno_name} {e}")
+    tty.debug(f"find must skip {path}: {e}")
 
 
 def _file_id(s: os.stat_result) -> Tuple[int, int]:

lib/spack/spack/audit.py

@@ -1356,14 +1356,8 @@ def _test_detection_by_executable(pkgs, debug_log, error_cls):
 
             def _compare_extra_attribute(_expected, _detected, *, _spec):
                 result = []
-                # Check items are of the same type
-                if not isinstance(_detected, type(_expected)):
-                    _summary = f'{pkg_name}: error when trying to detect "{_expected}"'
-                    _details = [f"{_detected} was detected instead"]
-                    return [error_cls(summary=_summary, details=_details)]
-
                 # If they are string expected is a regex
-                if isinstance(_expected, str):
+                if isinstance(_expected, str) and isinstance(_detected, str):
                     try:
                         _regex = re.compile(_expected)
                     except re.error:
@@ -1379,7 +1373,7 @@ def _compare_extra_attribute(_expected, _detected, *, _spec):
                         _details = [f"{_detected} does not match the regex"]
                         return [error_cls(summary=_summary, details=_details)]
 
-                if isinstance(_expected, dict):
+                elif isinstance(_expected, dict) and isinstance(_detected, dict):
                     _not_detected = set(_expected.keys()) - set(_detected.keys())
                     if _not_detected:
                         _summary = f"{pkg_name}: cannot detect some attributes for spec {_spec}"
@@ -1394,6 +1388,10 @@ def _compare_extra_attribute(_expected, _detected, *, _spec):
                         result.extend(
                             _compare_extra_attribute(_expected[_key], _detected[_key], _spec=_spec)
                         )
+                else:
+                    _summary = f'{pkg_name}: error when trying to detect "{_expected}"'
+                    _details = [f"{_detected} was detected instead"]
+                    return [error_cls(summary=_summary, details=_details)]
 
                 return result
 

lib/spack/spack/binary_distribution.py

@@ -23,7 +23,7 @@
 import urllib.request
 import warnings
 from contextlib import closing
-from typing import IO, Dict, Iterable, List, NamedTuple, Optional, Set, Tuple, Union
+from typing import IO, Callable, Dict, Iterable, List, NamedTuple, Optional, Set, Tuple, Union
 
 import llnl.util.filesystem as fsys
 import llnl.util.lang
@@ -591,32 +591,18 @@ def file_matches(f: IO[bytes], regex: llnl.util.lang.PatternBytes) -> bool:
         f.seek(0)
 
 
-def deps_to_relocate(spec):
-    """Return the transitive link and direct run dependencies of the spec.
-
-    This is a special traversal for dependencies we need to consider when relocating a package.
-
-    Package binaries, scripts, and other files may refer to the prefixes of  dependencies, so
-    we need to rewrite those locations when dependencies are in a different place at install time
-    than they were at build time.
-
-    This traversal covers transitive link dependencies and direct run dependencies because:
-
-    1. Spack adds RPATHs for transitive link dependencies so that packages can find needed
-       dependency libraries.
-    2. Packages may call any of their *direct* run dependencies (and may bake their paths into
-       binaries or scripts), so we also need to search for run dependency prefixes when relocating.
-
-    This returns a deduplicated list of transitive link dependencies and direct run dependencies.
-    """
-    deps = [
+def specs_to_relocate(spec: spack.spec.Spec) -> List[spack.spec.Spec]:
+    """Return the set of specs that may be referenced in the install prefix of the provided spec.
+    We currently include non-external transitive link and direct run dependencies."""
+    specs = [
         s
         for s in itertools.chain(
-            spec.traverse(root=True, deptype="link"), spec.dependencies(deptype="run")
+            spec.traverse(root=True, deptype="link", order="breadth", key=traverse.by_dag_hash),
+            spec.dependencies(deptype="run"),
         )
         if not s.external
     ]
-    return llnl.util.lang.dedupe(deps, key=lambda s: s.dag_hash())
+    return list(llnl.util.lang.dedupe(specs, key=lambda s: s.dag_hash()))
 
 
 def get_buildinfo_dict(spec):
@@ -630,7 +616,7 @@ def get_buildinfo_dict(spec):
         # "relocate_binaries": [],
         # "relocate_links": [],
         "hardlinks_deduped": True,
-        "hash_to_prefix": {d.dag_hash(): str(d.prefix) for d in deps_to_relocate(spec)},
+        "hash_to_prefix": {d.dag_hash(): str(d.prefix) for d in specs_to_relocate(spec)},
     }
 
 
@@ -683,19 +669,24 @@ def sign_specfile(key: str, specfile_path: str) -> str:
 
 
 def _read_specs_and_push_index(
-    file_list, read_method, cache_prefix, db: BuildCacheDatabase, temp_dir, concurrency
+    file_list: List[str],
+    read_method: Callable,
+    cache_prefix: str,
+    db: BuildCacheDatabase,
+    temp_dir: str,
+    concurrency: int,
 ):
     """Read all the specs listed in the provided list, using thread given thread parallelism,
         generate the index, and push it to the mirror.
 
     Args:
-        file_list (list(str)): List of urls or file paths pointing at spec files to read
+        file_list: List of urls or file paths pointing at spec files to read
         read_method: A function taking a single argument, either a url or a file path,
             and which reads the spec file at that location, and returns the spec.
-        cache_prefix (str): prefix of the build cache on s3 where index should be pushed.
+        cache_prefix: prefix of the build cache on s3 where index should be pushed.
         db: A spack database used for adding specs and then writing the index.
-        temp_dir (str): Location to write index.json and hash for pushing
-        concurrency (int): Number of parallel processes to use when fetching
+        temp_dir: Location to write index.json and hash for pushing
+        concurrency: Number of parallel processes to use when fetching
     """
     for file in file_list:
         contents = read_method(file)
@@ -875,9 +866,12 @@ def _url_generate_package_index(url: str, tmpdir: str, concurrency: int = 32):
     tty.debug(f"Retrieving spec descriptor files from {url} to build index")
 
     db = BuildCacheDatabase(tmpdir)
+    db._write()
 
     try:
-        _read_specs_and_push_index(file_list, read_fn, url, db, db.database_directory, concurrency)
+        _read_specs_and_push_index(
+            file_list, read_fn, url, db, str(db.database_directory), concurrency
+        )
     except Exception as e:
         raise GenerateIndexError(f"Encountered problem pushing package index to {url}: {e}") from e
 
@@ -1112,7 +1106,7 @@ def _exists_in_buildcache(spec: spack.spec.Spec, tmpdir: str, out_url: str) -> E
 
 
 def prefixes_to_relocate(spec):
-    prefixes = [s.prefix for s in deps_to_relocate(spec)]
+    prefixes = [s.prefix for s in specs_to_relocate(spec)]
     prefixes.append(spack.hooks.sbang.sbang_install_path())
     prefixes.append(str(spack.store.STORE.layout.root))
     return prefixes
@@ -2139,10 +2133,9 @@ def fetch_url_to_mirror(url):
 
 
 def dedupe_hardlinks_if_necessary(root, buildinfo):
-    """Updates a buildinfo dict for old archives that did
-    not dedupe hardlinks. De-duping hardlinks is necessary
-    when relocating files in parallel and in-place. This
-    means we must preserve inodes when relocating."""
+    """Updates a buildinfo dict for old archives that did not dedupe hardlinks. De-duping hardlinks
+    is necessary when relocating files in parallel and in-place. This means we must preserve inodes
+    when relocating."""
 
     # New archives don't need this.
     if buildinfo.get("hardlinks_deduped", False):
@@ -2171,65 +2164,47 @@ def dedupe_hardlinks_if_necessary(root, buildinfo):
         buildinfo[key] = new_list
 
 
-def relocate_package(spec):
-    """
-    Relocate the given package
-    """
-    workdir = str(spec.prefix)
-    buildinfo = read_buildinfo_file(workdir)
-    new_layout_root = str(spack.store.STORE.layout.root)
-    new_prefix = str(spec.prefix)
-    new_rel_prefix = str(os.path.relpath(new_prefix, new_layout_root))
-    new_spack_prefix = str(spack.paths.prefix)
-
-    old_sbang_install_path = None
-    if "sbang_install_path" in buildinfo:
-        old_sbang_install_path = str(buildinfo["sbang_install_path"])
+def relocate_package(spec: spack.spec.Spec) -> None:
+    """Relocate binaries and text files in the given spec prefix, based on its buildinfo file."""
+    buildinfo = read_buildinfo_file(spec.prefix)
     old_layout_root = str(buildinfo["buildpath"])
-    old_spack_prefix = str(buildinfo.get("spackprefix"))
-    old_rel_prefix = buildinfo.get("relative_prefix")
-    old_prefix = os.path.join(old_layout_root, old_rel_prefix)
-    rel = buildinfo.get("relative_rpaths", False)
 
-    # In the past prefix_to_hash was the default and externals were not dropped, so prefixes
-    # were not unique.
+    # Warn about old style tarballs created with the --rel flag (removed in Spack v0.20)
+    if buildinfo.get("relative_rpaths", False):
+        tty.warn(
+            f"Tarball for {spec} uses relative rpaths, which can cause library loading issues."
+        )
+
+    # In Spack 0.19 and older prefix_to_hash was the default and externals were not dropped, so
+    # prefixes were not unique.
     if "hash_to_prefix" in buildinfo:
         hash_to_old_prefix = buildinfo["hash_to_prefix"]
     elif "prefix_to_hash" in buildinfo:
-        hash_to_old_prefix = dict((v, k) for (k, v) in buildinfo["prefix_to_hash"].items())
+        hash_to_old_prefix = {v: k for (k, v) in buildinfo["prefix_to_hash"].items()}
     else:
-        hash_to_old_prefix = dict()
+        raise NewLayoutException(
+            "Package tarball was created from an install prefix with a different directory layout "
+            "and an older buildcache create implementation. It cannot be relocated."
+        )
 
-    if old_rel_prefix != new_rel_prefix and not hash_to_old_prefix:
-        msg = "Package tarball was created from an install "
-        msg += "prefix with a different directory layout and an older "
-        msg += "buildcache create implementation. It cannot be relocated."
-        raise NewLayoutException(msg)
+    prefix_to_prefix = {}
 
-    # Spurious replacements (e.g. sbang) will cause issues with binaries
-    # For example, the new sbang can be longer than the old one.
-    # Hence 2 dictionaries are maintained here.
-    prefix_to_prefix_text = collections.OrderedDict()
-    prefix_to_prefix_bin = collections.OrderedDict()
+    if "sbang_install_path" in buildinfo:
+        old_sbang_install_path = str(buildinfo["sbang_install_path"])
+        prefix_to_prefix[old_sbang_install_path] = spack.hooks.sbang.sbang_install_path()
 
-    if old_sbang_install_path:
-        install_path = spack.hooks.sbang.sbang_install_path()
-        prefix_to_prefix_text[old_sbang_install_path] = install_path
+    # First match specific prefix paths. Possibly the *local* install prefix of some dependency is
+    # in an upstream, so we cannot assume the original spack store root can be mapped uniformly to
+    # the new spack store root.
 
-    # First match specific prefix paths. Possibly the *local* install prefix
-    # of some dependency is in an upstream, so we cannot assume the original
-    # spack store root can be mapped uniformly to the new spack store root.
-    #
-    # If the spec is spliced, we need to handle the simultaneous mapping
-    # from the old install_tree to the new install_tree and from the build_spec
-    # to the spliced spec.
-    # Because foo.build_spec is foo for any non-spliced spec, we can simplify
-    # by checking for spliced-in nodes by checking for nodes not in the build_spec
-    # without any explicit check for whether the spec is spliced.
-    # An analog in this algorithm is any spec that shares a name or provides the same virtuals
-    # in the context of the relevant root spec. This ensures that the analog for a spec s
-    # is the spec that s replaced when we spliced.
-    relocation_specs = deps_to_relocate(spec)
+    # If the spec is spliced, we need to handle the simultaneous mapping from the old install_tree
+    # to the new install_tree and from the build_spec to the spliced spec. Because foo.build_spec
+    # is foo for any non-spliced spec, we can simplify by checking for spliced-in nodes by checking
+    # for nodes not in the build_spec without any explicit check for whether the spec is spliced.
+    # An analog in this algorithm is any spec that shares a name or provides the same virtuals in
+    # the context of the relevant root spec. This ensures that the analog for a spec s is the spec
+    # that s replaced when we spliced.
+    relocation_specs = specs_to_relocate(spec)
     build_spec_ids = set(id(s) for s in spec.build_spec.traverse(deptype=dt.ALL & ~dt.BUILD))
     for s in relocation_specs:
         analog = s
@@ -2248,98 +2223,48 @@ def relocate_package(spec):
         lookup_dag_hash = analog.dag_hash()
         if lookup_dag_hash in hash_to_old_prefix:
             old_dep_prefix = hash_to_old_prefix[lookup_dag_hash]
-            prefix_to_prefix_bin[old_dep_prefix] = str(s.prefix)
-            prefix_to_prefix_text[old_dep_prefix] = str(s.prefix)
+            prefix_to_prefix[old_dep_prefix] = str(s.prefix)
 
     # Only then add the generic fallback of install prefix -> install prefix.
-    prefix_to_prefix_text[old_prefix] = new_prefix
-    prefix_to_prefix_bin[old_prefix] = new_prefix
-    prefix_to_prefix_text[old_layout_root] = new_layout_root
-    prefix_to_prefix_bin[old_layout_root] = new_layout_root
+    prefix_to_prefix[old_layout_root] = str(spack.store.STORE.layout.root)
 
-    # This is vestigial code for the *old* location of sbang. Previously,
-    # sbang was a bash script, and it lived in the spack prefix. It is
-    # now a POSIX script that lives in the install prefix. Old packages
-    # will have the old sbang location in their shebangs.
-    orig_sbang = "#!/bin/bash {0}/bin/sbang".format(old_spack_prefix)
-    new_sbang = spack.hooks.sbang.sbang_shebang_line()
-    prefix_to_prefix_text[orig_sbang] = new_sbang
+    # Delete identity mappings from prefix_to_prefix
+    prefix_to_prefix = {k: v for k, v in prefix_to_prefix.items() if k != v}
 
-    tty.debug("Relocating package from", "%s to %s." % (old_layout_root, new_layout_root))
+    # If there's nothing to relocate, we're done.
+    if not prefix_to_prefix:
+        return
 
-    # Old archives maybe have hardlinks repeated.
-    dedupe_hardlinks_if_necessary(workdir, buildinfo)
+    for old, new in prefix_to_prefix.items():
+        tty.debug(f"Relocating: {old} => {new}.")
 
-    def is_backup_file(file):
-        return file.endswith("~")
+    # Old archives may have hardlinks repeated.
+    dedupe_hardlinks_if_necessary(spec.prefix, buildinfo)
 
     # Text files containing the prefix text
-    text_names = list()
-    for filename in buildinfo["relocate_textfiles"]:
-        text_name = os.path.join(workdir, filename)
-        # Don't add backup files generated by filter_file during install step.
-        if not is_backup_file(text_name):
-            text_names.append(text_name)
+    textfiles = [os.path.join(spec.prefix, f) for f in buildinfo["relocate_textfiles"]]
+    binaries = [os.path.join(spec.prefix, f) for f in buildinfo.get("relocate_binaries")]
+    links = [os.path.join(spec.prefix, f) for f in buildinfo.get("relocate_links", [])]
 
-    # If we are not installing back to the same install tree do the relocation
-    if old_prefix != new_prefix:
-        files_to_relocate = [
-            os.path.join(workdir, filename) for filename in buildinfo.get("relocate_binaries")
-        ]
-        # If the buildcache was not created with relativized rpaths
-        # do the relocation of path in binaries
-        platform = spack.platforms.by_name(spec.platform)
-        if "macho" in platform.binary_formats:
-            relocate.relocate_macho_binaries(
-                files_to_relocate,
-                old_layout_root,
-                new_layout_root,
-                prefix_to_prefix_bin,
-                rel,
-                old_prefix,
-                new_prefix,
-            )
-        elif "elf" in platform.binary_formats and not rel:
-            # The new ELF dynamic section relocation logic only handles absolute to
-            # absolute relocation.
-            relocate.new_relocate_elf_binaries(files_to_relocate, prefix_to_prefix_bin)
-        elif "elf" in platform.binary_formats and rel:
-            relocate.relocate_elf_binaries(
-                files_to_relocate,
-                old_layout_root,
-                new_layout_root,
-                prefix_to_prefix_bin,
-                rel,
-                old_prefix,
-                new_prefix,
-            )
+    platform = spack.platforms.by_name(spec.platform)
+    if "macho" in platform.binary_formats:
+        relocate.relocate_macho_binaries(binaries, prefix_to_prefix)
+    elif "elf" in platform.binary_formats:
+        relocate.relocate_elf_binaries(binaries, prefix_to_prefix)
 
-        # Relocate links to the new install prefix
-        links = [os.path.join(workdir, f) for f in buildinfo.get("relocate_links", [])]
-        relocate.relocate_links(links, prefix_to_prefix_bin)
+    relocate.relocate_links(links, prefix_to_prefix)
+    relocate.relocate_text(textfiles, prefix_to_prefix)
+    changed_files = relocate.relocate_text_bin(binaries, prefix_to_prefix)
 
-        # For all buildcaches
-        # relocate the install prefixes in text files including dependencies
-        relocate.relocate_text(text_names, prefix_to_prefix_text)
-
-        # relocate the install prefixes in binary files including dependencies
-        changed_files = relocate.relocate_text_bin(files_to_relocate, prefix_to_prefix_bin)
-
-        # Add ad-hoc signatures to patched macho files when on macOS.
-        if "macho" in platform.binary_formats and sys.platform == "darwin":
-            codesign = which("codesign")
-            if not codesign:
-                return
-            for binary in changed_files:
-                # preserve the original inode by running codesign on a copy
-                with fsys.edit_in_place_through_temporary_file(binary) as tmp_binary:
-                    codesign("-fs-", tmp_binary)
-
-    # If we are installing back to the same location
-    # relocate the sbang location if the spack directory changed
-    else:
-        if old_spack_prefix != new_spack_prefix:
-            relocate.relocate_text(text_names, prefix_to_prefix_text)
+    # Add ad-hoc signatures to patched macho files when on macOS.
+    if "macho" in platform.binary_formats and sys.platform == "darwin":
+        codesign = which("codesign")
+        if not codesign:
+            return
+        for binary in changed_files:
+            # preserve the original inode by running codesign on a copy
+            with fsys.edit_in_place_through_temporary_file(binary) as tmp_binary:
+                codesign("-fs-", tmp_binary)
 
 
 def _extract_inner_tarball(spec, filename, extract_to, signature_required: bool, remote_checksum):

lib/spack/spack/bootstrap/_common.py

@@ -10,7 +10,9 @@
 import sys
 import sysconfig
 import warnings
-from typing import Dict, Optional, Sequence, Union
+from typing import Optional, Sequence, Union
+
+from typing_extensions import TypedDict
 
 import archspec.cpu
 
@@ -18,13 +20,17 @@
 from llnl.util import tty
 
 import spack.platforms
+import spack.spec
 import spack.store
 import spack.util.environment
 import spack.util.executable
 
 from .config import spec_for_current_python
 
-QueryInfo = Dict[str, "spack.spec.Spec"]
+
+class QueryInfo(TypedDict, total=False):
+    spec: spack.spec.Spec
+    command: spack.util.executable.Executable
 
 
 def _python_import(module: str) -> bool:
@@ -211,7 +217,9 @@ def _executables_in_store(
             ):
                 spack.util.environment.path_put_first("PATH", [bin_dir])
                 if query_info is not None:
-                    query_info["command"] = spack.util.executable.which(*executables, path=bin_dir)
+                    query_info["command"] = spack.util.executable.which(
+                        *executables, path=bin_dir, required=True
+                    )
                     query_info["spec"] = concrete_spec
                 return True
     return False

lib/spack/spack/bootstrap/core.py

@@ -34,6 +34,7 @@
 from llnl.util.lang import GroupedExceptionHandler
 
 import spack.binary_distribution
+import spack.concretize
 import spack.config
 import spack.detection
 import spack.mirrors.mirror
@@ -47,7 +48,13 @@
 import spack.version
 from spack.installer import PackageInstaller
 
-from ._common import _executables_in_store, _python_import, _root_spec, _try_import_from_store
+from ._common import (
+    QueryInfo,
+    _executables_in_store,
+    _python_import,
+    _root_spec,
+    _try_import_from_store,
+)
 from .clingo import ClingoBootstrapConcretizer
 from .config import spack_python_interpreter, spec_for_current_python
 
@@ -134,7 +141,7 @@ class BuildcacheBootstrapper(Bootstrapper):
 
     def __init__(self, conf) -> None:
         super().__init__(conf)
-        self.last_search: Optional[ConfigDictionary] = None
+        self.last_search: Optional[QueryInfo] = None
         self.config_scope_name = f"bootstrap_buildcache-{uuid.uuid4()}"
 
     @staticmethod
@@ -211,14 +218,14 @@ def _install_and_test(
                 for _, pkg_hash, pkg_sha256 in item["binaries"]:
                     self._install_by_hash(pkg_hash, pkg_sha256, bincache_platform)
 
-                info: ConfigDictionary = {}
+                info: QueryInfo = {}
                 if test_fn(query_spec=abstract_spec, query_info=info):
                     self.last_search = info
                     return True
         return False
 
     def try_import(self, module: str, abstract_spec_str: str) -> bool:
-        info: ConfigDictionary
+        info: QueryInfo
         test_fn, info = functools.partial(_try_import_from_store, module), {}
         if test_fn(query_spec=abstract_spec_str, query_info=info):
             return True
@@ -231,7 +238,7 @@ def try_import(self, module: str, abstract_spec_str: str) -> bool:
         return self._install_and_test(abstract_spec, bincache_platform, data, test_fn)
 
     def try_search_path(self, executables: Tuple[str], abstract_spec_str: str) -> bool:
-        info: ConfigDictionary
+        info: QueryInfo
         test_fn, info = functools.partial(_executables_in_store, executables), {}
         if test_fn(query_spec=abstract_spec_str, query_info=info):
             self.last_search = info
@@ -249,11 +256,11 @@ class SourceBootstrapper(Bootstrapper):
 
     def __init__(self, conf) -> None:
         super().__init__(conf)
-        self.last_search: Optional[ConfigDictionary] = None
+        self.last_search: Optional[QueryInfo] = None
         self.config_scope_name = f"bootstrap_source-{uuid.uuid4()}"
 
     def try_import(self, module: str, abstract_spec_str: str) -> bool:
-        info: ConfigDictionary = {}
+        info: QueryInfo = {}
         if _try_import_from_store(module, abstract_spec_str, query_info=info):
             self.last_search = info
             return True
@@ -270,10 +277,10 @@ def try_import(self, module: str, abstract_spec_str: str) -> bool:
                 bootstrapper = ClingoBootstrapConcretizer(configuration=spack.config.CONFIG)
                 concrete_spec = bootstrapper.concretize()
             else:
-                concrete_spec = spack.spec.Spec(
+                abstract_spec = spack.spec.Spec(
                     abstract_spec_str + " ^" + spec_for_current_python()
                 )
-                concrete_spec.concretize()
+                concrete_spec = spack.concretize.concretize_one(abstract_spec)
 
         msg = "[BOOTSTRAP MODULE {0}] Try installing '{1}' from sources"
         tty.debug(msg.format(module, abstract_spec_str))
@@ -288,7 +295,7 @@ def try_import(self, module: str, abstract_spec_str: str) -> bool:
         return False
 
     def try_search_path(self, executables: Tuple[str], abstract_spec_str: str) -> bool:
-        info: ConfigDictionary = {}
+        info: QueryInfo = {}
         if _executables_in_store(executables, abstract_spec_str, query_info=info):
             self.last_search = info
             return True
@@ -299,7 +306,7 @@ def try_search_path(self, executables: Tuple[str], abstract_spec_str: str) -> bo
         # might reduce compilation time by a fair amount
         _add_externals_if_missing()
 
-        concrete_spec = spack.spec.Spec(abstract_spec_str).concretized()
+        concrete_spec = spack.concretize.concretize_one(abstract_spec_str)
         msg = "[BOOTSTRAP] Try installing '{0}' from sources"
         tty.debug(msg.format(abstract_spec_str))
         with spack.config.override(self.mirror_scope):
@@ -414,6 +421,7 @@ def ensure_executables_in_path_or_raise(
                     current_bootstrapper.last_search["spec"],
                     current_bootstrapper.last_search["command"],
                 )
+                assert cmd is not None, "expected an Executable"
                 cmd.add_default_envmod(
                     spack.user_environment.environment_modifications_for_specs(
                         concrete_spec, set_package_py_globals=False

lib/spack/spack/build_environment.py

@@ -44,7 +44,19 @@
 from enum import Flag, auto
 from itertools import chain
 from multiprocessing.connection import Connection
-from typing import Callable, Dict, List, Optional, Set, Tuple
+from typing import (
+    Callable,
+    Dict,
+    List,
+    Optional,
+    Sequence,
+    Set,
+    TextIO,
+    Tuple,
+    Type,
+    Union,
+    overload,
+)
 
 import archspec.cpu
 
@@ -146,48 +158,128 @@ def get_effective_jobs(jobs, parallel=True, supports_jobserver=False):
 
 
 class MakeExecutable(Executable):
-    """Special callable executable object for make so the user can specify
-    parallelism options on a per-invocation basis.  Specifying
-    'parallel' to the call will override whatever the package's
-    global setting is, so you can either default to true or false and
-    override particular calls. Specifying 'jobs_env' to a particular
-    call will name an environment variable which will be set to the
-    parallelism level (without affecting the normal invocation with
-    -j).
+    """Special callable executable object for make so the user can specify parallelism options
+    on a per-invocation basis.
     """
 
-    def __init__(self, name, jobs, **kwargs):
-        supports_jobserver = kwargs.pop("supports_jobserver", True)
-        super().__init__(name, **kwargs)
+    def __init__(self, name: str, *, jobs: int, supports_jobserver: bool = True) -> None:
+        super().__init__(name)
         self.supports_jobserver = supports_jobserver
         self.jobs = jobs
 
-    def __call__(self, *args, **kwargs):
-        """parallel, and jobs_env from kwargs are swallowed and used here;
-        remaining arguments are passed through to the superclass.
-        """
-        parallel = kwargs.pop("parallel", True)
-        jobs_env = kwargs.pop("jobs_env", None)
-        jobs_env_supports_jobserver = kwargs.pop("jobs_env_supports_jobserver", False)
+    @overload
+    def __call__(
+        self,
+        *args: str,
+        parallel: bool = ...,
+        jobs_env: Optional[str] = ...,
+        jobs_env_supports_jobserver: bool = ...,
+        fail_on_error: bool = ...,
+        ignore_errors: Union[int, Sequence[int]] = ...,
+        ignore_quotes: Optional[bool] = ...,
+        timeout: Optional[int] = ...,
+        env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        extra_env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        input: Optional[TextIO] = ...,
+        output: Union[Optional[TextIO], str] = ...,
+        error: Union[Optional[TextIO], str] = ...,
+        _dump_env: Optional[Dict[str, str]] = ...,
+    ) -> None: ...
 
+    @overload
+    def __call__(
+        self,
+        *args: str,
+        parallel: bool = ...,
+        jobs_env: Optional[str] = ...,
+        jobs_env_supports_jobserver: bool = ...,
+        fail_on_error: bool = ...,
+        ignore_errors: Union[int, Sequence[int]] = ...,
+        ignore_quotes: Optional[bool] = ...,
+        timeout: Optional[int] = ...,
+        env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        extra_env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        input: Optional[TextIO] = ...,
+        output: Union[Type[str], Callable] = ...,
+        error: Union[Optional[TextIO], str, Type[str], Callable] = ...,
+        _dump_env: Optional[Dict[str, str]] = ...,
+    ) -> str: ...
+
+    @overload
+    def __call__(
+        self,
+        *args: str,
+        parallel: bool = ...,
+        jobs_env: Optional[str] = ...,
+        jobs_env_supports_jobserver: bool = ...,
+        fail_on_error: bool = ...,
+        ignore_errors: Union[int, Sequence[int]] = ...,
+        ignore_quotes: Optional[bool] = ...,
+        timeout: Optional[int] = ...,
+        env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        extra_env: Optional[Union[Dict[str, str], EnvironmentModifications]] = ...,
+        input: Optional[TextIO] = ...,
+        output: Union[Optional[TextIO], str, Type[str], Callable] = ...,
+        error: Union[Type[str], Callable] = ...,
+        _dump_env: Optional[Dict[str, str]] = ...,
+    ) -> str: ...
+
+    def __call__(
+        self,
+        *args: str,
+        parallel: bool = True,
+        jobs_env: Optional[str] = None,
+        jobs_env_supports_jobserver: bool = False,
+        **kwargs,
+    ) -> Optional[str]:
+        """Runs this "make" executable in a subprocess.
+
+        Args:
+            parallel: if False, parallelism is disabled
+            jobs_env: environment variable that will be set to the current level of parallelism
+            jobs_env_supports_jobserver: whether the jobs env supports a job server
+
+        For all the other **kwargs, refer to the base class.
+        """
         jobs = get_effective_jobs(
             self.jobs, parallel=parallel, supports_jobserver=self.supports_jobserver
         )
         if jobs is not None:
-            args = ("-j{0}".format(jobs),) + args
+            args = (f"-j{jobs}",) + args
 
         if jobs_env:
-            # Caller wants us to set an environment variable to
-            # control the parallelism.
+            # Caller wants us to set an environment variable to control the parallelism
             jobs_env_jobs = get_effective_jobs(
                 self.jobs, parallel=parallel, supports_jobserver=jobs_env_supports_jobserver
             )
             if jobs_env_jobs is not None:
-                kwargs["extra_env"] = {jobs_env: str(jobs_env_jobs)}
+                extra_env = kwargs.setdefault("extra_env", {})
+                extra_env.update({jobs_env: str(jobs_env_jobs)})
 
         return super().__call__(*args, **kwargs)
 
 
+class UndeclaredDependencyError(spack.error.SpackError):
+    """Raised if a dependency is invoking an executable through a module global, without
+    declaring a dependency on it.
+    """
+
+
+class DeprecatedExecutable:
+    def __init__(self, pkg: str, exe: str, exe_pkg: str) -> None:
+        self.pkg = pkg
+        self.exe = exe
+        self.exe_pkg = exe_pkg
+
+    def __call__(self, *args, **kwargs):
+        raise UndeclaredDependencyError(
+            f"{self.pkg} is using {self.exe} without declaring a dependency on {self.exe_pkg}"
+        )
+
+    def add_default_env(self, key: str, value: str):
+        self.__call__()
+
+
 def clean_environment():
     # Stuff in here sanitizes the build environment to eliminate
     # anything the user has set that may interfere. We apply it immediately
@@ -621,10 +713,9 @@ def set_package_py_globals(pkg, context: Context = Context.BUILD):
         module.std_meson_args = spack.build_systems.meson.MesonBuilder.std_args(pkg)
         module.std_pip_args = spack.build_systems.python.PythonPipBuilder.std_args(pkg)
 
-    # TODO: make these build deps that can be installed if not found.
-    module.make = MakeExecutable("make", jobs)
-    module.gmake = MakeExecutable("gmake", jobs)
-    module.ninja = MakeExecutable("ninja", jobs, supports_jobserver=False)
+    module.make = DeprecatedExecutable(pkg.name, "make", "gmake")
+    module.gmake = DeprecatedExecutable(pkg.name, "gmake", "gmake")
+    module.ninja = DeprecatedExecutable(pkg.name, "ninja", "ninja")
     # TODO: johnwparent: add package or builder support to define these build tools
     # for now there is no entrypoint for builders to define these on their
     # own

lib/spack/spack/build_systems/cached_cmake.py

@@ -298,7 +298,14 @@ def initconfig_hardware_entries(self):
     def std_initconfig_entries(self):
         cmake_prefix_path_env = os.environ["CMAKE_PREFIX_PATH"]
         cmake_prefix_path = cmake_prefix_path_env.replace(os.pathsep, ";")
-
+        complete_rpath_list = ";".join(
+            [
+                self.pkg.spec.prefix.lib,
+                self.pkg.spec.prefix.lib64,
+                *os.environ.get("SPACK_COMPILER_EXTRA_RPATHS", "").split(":"),
+                *os.environ.get("SPACK_COMPILER_IMPLICIT_RPATHS", "").split(":"),
+            ]
+        )
         return [
             "#------------------{0}".format("-" * 60),
             "# !!!! This is a generated file, edit at own risk !!!!",
@@ -307,6 +314,8 @@ def std_initconfig_entries(self):
             "#------------------{0}\n".format("-" * 60),
             cmake_cache_string("CMAKE_PREFIX_PATH", cmake_prefix_path),
             cmake_cache_string("CMAKE_INSTALL_RPATH_USE_LINK_PATH", "ON"),
+            cmake_cache_string("CMAKE_BUILD_RPATH", complete_rpath_list),
+            cmake_cache_string("CMAKE_INSTALL_RPATH", complete_rpath_list),
             self.define_cmake_cache_from_variant("CMAKE_BUILD_TYPE", "build_type"),
         ]
 

lib/spack/spack/build_systems/cargo.py

@@ -71,13 +71,16 @@ def build_directory(self):
     @property
     def build_args(self):
         """Arguments for ``cargo build``."""
-        return []
+        return ["-j", str(self.pkg.module.make_jobs)]
 
     @property
     def check_args(self):
         """Argument for ``cargo test`` during check phase"""
         return []
 
+    def setup_build_environment(self, env):
+        env.set("CARGO_HOME", self.stage.path)
+
     def build(self, pkg, spec, prefix):
         """Runs ``cargo install`` in the source directory"""
         with fs.working_dir(self.build_directory):

lib/spack/spack/build_systems/perl.py

@@ -10,8 +10,9 @@
 import spack.builder
 import spack.package_base
 import spack.phase_callbacks
-from spack.directives import build_system, extends
+from spack.directives import build_system, depends_on, extends
 from spack.install_test import SkipTest, test_part
+from spack.multimethod import when
 from spack.util.executable import Executable
 
 from ._checks import BuilderWithDefaults, execute_build_time_tests
@@ -28,7 +29,9 @@ class PerlPackage(spack.package_base.PackageBase):
 
     build_system("perl")
 
-    extends("perl", when="build_system=perl")
+    with when("build_system=perl"):
+        extends("perl")
+        depends_on("gmake", type="build")
 
     @property
     @memoized

lib/spack/spack/build_systems/qmake.py

@@ -27,6 +27,7 @@ class QMakePackage(spack.package_base.PackageBase):
     build_system("qmake")
 
     depends_on("qmake", type="build", when="build_system=qmake")
+    depends_on("gmake", type="build")
 
 
 @spack.builder.builder("qmake")

lib/spack/spack/build_systems/r.py

@@ -94,7 +94,7 @@ def list_url(cls):
         if cls.cran:
             return f"https://cloud.r-project.org/src/contrib/Archive/{cls.cran}/"
 
-    @property
-    def git(self):
-        if self.bioc:
-            return f"https://git.bioconductor.org/packages/{self.bioc}"
+    @lang.classproperty
+    def git(cls):
+        if cls.bioc:
+            return f"https://git.bioconductor.org/packages/{cls.bioc}"

lib/spack/spack/cmd/__init__.py

@@ -171,7 +171,9 @@ def quote_kvp(string: str) -> str:
 
 
 def parse_specs(
-    args: Union[str, List[str]], concretize: bool = False, tests: bool = False
+    args: Union[str, List[str]],
+    concretize: bool = False,
+    tests: spack.concretize.TestsType = False,
 ) -> List[spack.spec.Spec]:
     """Convenience function for parsing arguments from specs.  Handles common
     exceptions and dies if there are errors.
@@ -183,11 +185,13 @@ def parse_specs(
     if not concretize:
         return specs
 
-    to_concretize = [(s, None) for s in specs]
+    to_concretize: List[spack.concretize.SpecPairInput] = [(s, None) for s in specs]
     return _concretize_spec_pairs(to_concretize, tests=tests)
 
 
-def _concretize_spec_pairs(to_concretize, tests=False):
+def _concretize_spec_pairs(
+    to_concretize: List[spack.concretize.SpecPairInput], tests: spack.concretize.TestsType = False
+) -> List[spack.spec.Spec]:
     """Helper method that concretizes abstract specs from a list of abstract,concrete pairs.
 
     Any spec with a concrete spec associated with it will concretize to that spec. Any spec
@@ -198,7 +202,7 @@ def _concretize_spec_pairs(to_concretize, tests=False):
     # Special case for concretizing a single spec
     if len(to_concretize) == 1:
         abstract, concrete = to_concretize[0]
-        return [concrete or abstract.concretized()]
+        return [concrete or spack.concretize.concretize_one(abstract, tests=tests)]
 
     # Special case if every spec is either concrete or has an abstract hash
     if all(
@@ -250,9 +254,9 @@ def matching_spec_from_env(spec):
     """
     env = ev.active_environment()
     if env:
-        return env.matching_spec(spec) or spec.concretized()
+        return env.matching_spec(spec) or spack.concretize.concretize_one(spec)
     else:
-        return spec.concretized()
+        return spack.concretize.concretize_one(spec)
 
 
 def matching_specs_from_env(specs):
@@ -293,7 +297,7 @@ def disambiguate_spec(
 
 def disambiguate_spec_from_hashes(
     spec: spack.spec.Spec,
-    hashes: List[str],
+    hashes: Optional[List[str]],
     local: bool = False,
     installed: Union[bool, InstallRecordStatus] = True,
     first: bool = False,

lib/spack/spack/cmd/bootstrap.py

@@ -14,9 +14,9 @@
 import spack.bootstrap
 import spack.bootstrap.config
 import spack.bootstrap.core
+import spack.concretize
 import spack.config
 import spack.mirrors.utils
-import spack.spec
 import spack.stage
 import spack.util.path
 import spack.util.spack_yaml
@@ -397,7 +397,7 @@ def _mirror(args):
         llnl.util.tty.msg(msg.format(spec_str, mirror_dir))
         # Suppress tty from the call below for terser messages
         llnl.util.tty.set_msg_enabled(False)
-        spec = spack.spec.Spec(spec_str).concretized()
+        spec = spack.concretize.concretize_one(spec_str)
         for node in spec.traverse():
             spack.mirrors.utils.create(mirror_dir, [node])
         llnl.util.tty.set_msg_enabled(True)

lib/spack/spack/cmd/buildcache.py

@@ -16,6 +16,7 @@
 
 import spack.binary_distribution as bindist
 import spack.cmd
+import spack.concretize
 import spack.config
 import spack.deptypes as dt
 import spack.environment as ev
@@ -554,8 +555,7 @@ def check_fn(args: argparse.Namespace):
         tty.msg("No specs provided, exiting.")
         return
 
-    for spec in specs:
-        spec.concretize()
+    specs = [spack.concretize.concretize_one(s) for s in specs]
 
     # Next see if there are any configured binary mirrors
     configured_mirrors = spack.config.get("mirrors", scope=args.scope)
@@ -623,7 +623,7 @@ def save_specfile_fn(args):
     root = specs[0]
 
     if not root.concrete:
-        root.concretize()
+        root = spack.concretize.concretize_one(root)
 
     save_dependency_specfiles(
         root, args.specfile_dir, dependencies=spack.cmd.parse_specs(args.specs)

lib/spack/spack/cmd/deprecate.py

@@ -18,6 +18,7 @@
 from llnl.util.symlink import symlink
 
 import spack.cmd
+import spack.concretize
 import spack.environment as ev
 import spack.installer
 import spack.store
@@ -103,7 +104,7 @@ def deprecate(parser, args):
     )
 
     if args.install:
-        deprecator = specs[1].concretized()
+        deprecator = spack.concretize.concretize_one(specs[1])
     else:
         deprecator = spack.cmd.disambiguate_spec(specs[1], env, local=True)
 

lib/spack/spack/cmd/dev_build.py

@@ -10,6 +10,7 @@
 import spack.build_environment
 import spack.cmd
 import spack.cmd.common.arguments
+import spack.concretize
 import spack.config
 import spack.repo
 from spack.cmd.common import arguments
@@ -114,7 +115,7 @@ def dev_build(self, args):
 
     # Forces the build to run out of the source directory.
     spec.constrain("dev_path=%s" % source_path)
-    spec.concretize()
+    spec = spack.concretize.concretize_one(spec)
 
     if spec.installed:
         tty.error("Already installed in %s" % spec.prefix)

lib/spack/spack/cmd/install.py

@@ -13,6 +13,7 @@
 from llnl.util import lang, tty
 
 import spack.cmd
+import spack.concretize
 import spack.config
 import spack.environment as ev
 import spack.paths
@@ -450,7 +451,7 @@ def concrete_specs_from_file(args):
             else:
                 s = spack.spec.Spec.from_json(f)
 
-        concretized = s.concretized()
+        concretized = spack.concretize.concretize_one(s)
         if concretized.dag_hash() != s.dag_hash():
             msg = 'skipped invalid file "{0}". '
             msg += "The file does not contain a concrete spec."

lib/spack/spack/cmd/make_installer.py

@@ -7,9 +7,9 @@
 
 from llnl.path import convert_to_posix_path
 
+import spack.concretize
 import spack.paths
 import spack.util.executable
-from spack.spec import Spec
 
 description = "generate Windows installer"
 section = "admin"
@@ -65,8 +65,7 @@ def make_installer(parser, args):
     """
     if sys.platform == "win32":
         output_dir = args.output_dir
-        cmake_spec = Spec("cmake")
-        cmake_spec.concretize()
+        cmake_spec = spack.concretize.concretize_one("cmake")
         cmake_path = os.path.join(cmake_spec.prefix, "bin", "cmake.exe")
         cpack_path = os.path.join(cmake_spec.prefix, "bin", "cpack.exe")
         spack_source = args.spack_source

lib/spack/spack/cmd/mirror.py

@@ -492,7 +492,7 @@ def extend_with_additional_versions(specs, num_versions):
         mirror_specs = spack.mirrors.utils.get_all_versions(specs)
     else:
         mirror_specs = spack.mirrors.utils.get_matching_versions(specs, num_versions=num_versions)
-    mirror_specs = [x.concretized() for x in mirror_specs]
+    mirror_specs = [spack.concretize.concretize_one(x) for x in mirror_specs]
     return mirror_specs
 
 

lib/spack/spack/cmd/uninstall.py

@@ -144,7 +144,7 @@ def is_installed(spec):
         record = spack.store.STORE.db.query_local_by_spec_hash(spec.dag_hash())
         return record and record.installed
 
-    specs = traverse.traverse_nodes(
+    all_specs = traverse.traverse_nodes(
         specs,
         root=False,
         order="breadth",
@@ -155,7 +155,7 @@ def is_installed(spec):
     )
 
     with spack.store.STORE.db.read_transaction():
-        return [spec for spec in specs if is_installed(spec)]
+        return [spec for spec in all_specs if is_installed(spec)]
 
 
 def dependent_environments(

lib/spack/spack/compiler.py

@@ -749,12 +749,18 @@ def __init__(self, compiler, feature, flag_name, ver_string=None):
 class CompilerCacheEntry:
     """Deserialized cache entry for a compiler"""
 
-    __slots__ = ["c_compiler_output", "real_version"]
+    __slots__ = ("c_compiler_output", "real_version")
 
     def __init__(self, c_compiler_output: Optional[str], real_version: str):
         self.c_compiler_output = c_compiler_output
         self.real_version = real_version
 
+    @property
+    def empty(self) -> bool:
+        """Sometimes the compiler is temporarily broken, preventing us from getting output. The
+        call site determines if that is a problem."""
+        return self.c_compiler_output is None
+
     @classmethod
     def from_dict(cls, data: Dict[str, Optional[str]]):
         if not isinstance(data, dict):
@@ -792,9 +798,10 @@ def __init__(self, cache: "FileCache") -> None:
         self.cache.init_entry(self.name)
         self._data: Dict[str, Dict[str, Optional[str]]] = {}
 
-    def _get_entry(self, key: str) -> Optional[CompilerCacheEntry]:
+    def _get_entry(self, key: str, *, allow_empty: bool) -> Optional[CompilerCacheEntry]:
         try:
-            return CompilerCacheEntry.from_dict(self._data[key])
+            entry = CompilerCacheEntry.from_dict(self._data[key])
+            return entry if allow_empty or not entry.empty else None
         except ValueError:
             del self._data[key]
         except KeyError:
@@ -812,7 +819,7 @@ def get(self, compiler: Compiler) -> CompilerCacheEntry:
             self._data = {}
 
         key = self._key(compiler)
-        value = self._get_entry(key)
+        value = self._get_entry(key, allow_empty=False)
         if value is not None:
             return value
 
@@ -826,7 +833,7 @@ def get(self, compiler: Compiler) -> CompilerCacheEntry:
                 self._data = {}
 
             # Use cache entry that may have been created by another process in the meantime.
-            entry = self._get_entry(key)
+            entry = self._get_entry(key, allow_empty=True)
 
             # Finally compute the cache entry
             if entry is None:

lib/spack/spack/concretize.py

@@ -5,7 +5,7 @@
 import sys
 import time
 from contextlib import contextmanager
-from typing import Iterable, Optional, Sequence, Tuple, Union
+from typing import Iterable, List, Optional, Sequence, Tuple, Union
 
 import llnl.util.tty as tty
 
@@ -35,14 +35,14 @@ def enable_compiler_existence_check():
     CHECK_COMPILER_EXISTENCE = saved
 
 
+SpecPairInput = Tuple[Spec, Optional[Spec]]
 SpecPair = Tuple[Spec, Spec]
-SpecLike = Union[Spec, str]
 TestsType = Union[bool, Iterable[str]]
 
 
-def concretize_specs_together(
-    abstract_specs: Sequence[SpecLike], tests: TestsType = False
-) -> Sequence[Spec]:
+def _concretize_specs_together(
+    abstract_specs: Sequence[Spec], tests: TestsType = False
+) -> List[Spec]:
     """Given a number of specs as input, tries to concretize them together.
 
     Args:
@@ -50,17 +50,16 @@ def concretize_specs_together(
         tests: list of package names for which to consider tests dependencies. If True, all nodes
             will have test dependencies. If False, test dependencies will be disregarded.
     """
-    import spack.solver.asp
+    from spack.solver.asp import Solver
 
     allow_deprecated = spack.config.get("config:deprecated", False)
-    solver = spack.solver.asp.Solver()
-    result = solver.solve(abstract_specs, tests=tests, allow_deprecated=allow_deprecated)
+    result = Solver().solve(abstract_specs, tests=tests, allow_deprecated=allow_deprecated)
     return [s.copy() for s in result.specs]
 
 
 def concretize_together(
-    spec_list: Sequence[SpecPair], tests: TestsType = False
-) -> Sequence[SpecPair]:
+    spec_list: Sequence[SpecPairInput], tests: TestsType = False
+) -> List[SpecPair]:
     """Given a number of specs as input, tries to concretize them together.
 
     Args:
@@ -71,13 +70,13 @@ def concretize_together(
     """
     to_concretize = [concrete if concrete else abstract for abstract, concrete in spec_list]
     abstract_specs = [abstract for abstract, _ in spec_list]
-    concrete_specs = concretize_specs_together(to_concretize, tests=tests)
+    concrete_specs = _concretize_specs_together(to_concretize, tests=tests)
     return list(zip(abstract_specs, concrete_specs))
 
 
 def concretize_together_when_possible(
-    spec_list: Sequence[SpecPair], tests: TestsType = False
-) -> Sequence[SpecPair]:
+    spec_list: Sequence[SpecPairInput], tests: TestsType = False
+) -> List[SpecPair]:
     """Given a number of specs as input, tries to concretize them together to the extent possible.
 
     See documentation for ``unify: when_possible`` concretization for the precise definition of
@@ -89,7 +88,7 @@ def concretize_together_when_possible(
         tests: list of package names for which to consider tests dependencies. If True, all nodes
             will have test dependencies. If False, test dependencies will be disregarded.
     """
-    import spack.solver.asp
+    from spack.solver.asp import Solver
 
     to_concretize = [concrete if concrete else abstract for abstract, concrete in spec_list]
     old_concrete_to_abstract = {
@@ -97,9 +96,8 @@ def concretize_together_when_possible(
     }
 
     result_by_user_spec = {}
-    solver = spack.solver.asp.Solver()
     allow_deprecated = spack.config.get("config:deprecated", False)
-    for result in solver.solve_in_rounds(
+    for result in Solver().solve_in_rounds(
         to_concretize, tests=tests, allow_deprecated=allow_deprecated
     ):
         result_by_user_spec.update(result.specs_by_input)
@@ -113,8 +111,8 @@ def concretize_together_when_possible(
 
 
 def concretize_separately(
-    spec_list: Sequence[SpecPair], tests: TestsType = False
-) -> Sequence[SpecPair]:
+    spec_list: Sequence[SpecPairInput], tests: TestsType = False
+) -> List[SpecPair]:
     """Concretizes the input specs separately from each other.
 
     Args:
@@ -123,7 +121,7 @@ def concretize_separately(
         tests: list of package names for which to consider tests dependencies. If True, all nodes
             will have test dependencies. If False, test dependencies will be disregarded.
     """
-    import spack.bootstrap
+    from spack.bootstrap import ensure_bootstrap_configuration, ensure_clingo_importable_or_raise
 
     to_concretize = [abstract for abstract, concrete in spec_list if not concrete]
     args = [
@@ -133,8 +131,8 @@ def concretize_separately(
     ]
     ret = [(i, abstract) for i, abstract in enumerate(to_concretize) if abstract.concrete]
     # Ensure we don't try to bootstrap clingo in parallel
-    with spack.bootstrap.ensure_bootstrap_configuration():
-        spack.bootstrap.ensure_clingo_importable_or_raise()
+    with ensure_bootstrap_configuration():
+        ensure_clingo_importable_or_raise()
 
     # Ensure all the indexes have been built or updated, since
     # otherwise the processes in the pool may timeout on waiting
@@ -189,10 +187,52 @@ def _concretize_task(packed_arguments: Tuple[int, str, TestsType]) -> Tuple[int,
     index, spec_str, tests = packed_arguments
     with tty.SuppressOutput(msg_enabled=False):
         start = time.time()
-        spec = Spec(spec_str).concretized(tests=tests)
+        spec = concretize_one(Spec(spec_str), tests=tests)
         return index, spec, time.time() - start
 
 
+def concretize_one(spec: Union[str, Spec], tests: TestsType = False) -> Spec:
+    """Return a concretized copy of the given spec.
+
+    Args:
+        tests: if False disregard 'test' dependencies, if a list of names activate them for
+            the packages in the list, if True activate 'test' dependencies for all packages.
+    """
+    from spack.solver.asp import Solver, SpecBuilder
+
+    if isinstance(spec, str):
+        spec = Spec(spec)
+    spec = spec.lookup_hash()
+
+    if spec.concrete:
+        return spec.copy()
+
+    for node in spec.traverse():
+        if not node.name:
+            raise spack.error.SpecError(
+                f"Spec {node} has no name; cannot concretize an anonymous spec"
+            )
+
+    allow_deprecated = spack.config.get("config:deprecated", False)
+    result = Solver().solve([spec], tests=tests, allow_deprecated=allow_deprecated)
+
+    # take the best answer
+    opt, i, answer = min(result.answers)
+    name = spec.name
+    # TODO: Consolidate this code with similar code in solve.py
+    if spec.virtual:
+        providers = [s.name for s in answer.values() if s.package.provides(name)]
+        name = providers[0]
+
+    node = SpecBuilder.make_node(pkg=name)
+    assert (
+        node in answer
+    ), f"cannot find {name} in the list of specs {','.join([n.pkg for n in answer.keys()])}"
+
+    concretized = answer[node]
+    return concretized
+
+
 class UnavailableCompilerVersionError(spack.error.SpackError):
     """Raised when there is no available compiler that satisfies a
     compiler spec."""

lib/spack/spack/config.py

@@ -951,12 +951,6 @@ def set(path: str, value: Any, scope: Optional[str] = None) -> None:
     return CONFIG.set(path, value, scope)
 
 
-def add_default_platform_scope(platform: str) -> None:
-    plat_name = os.path.join("defaults", platform)
-    plat_path = os.path.join(CONFIGURATION_DEFAULTS_PATH[1], platform)
-    CONFIG.push_scope(DirectoryConfigScope(plat_name, plat_path))
-
-
 def scopes() -> Dict[str, ConfigScope]:
     """Convenience function to get list of configuration scopes."""
     return CONFIG.scopes

lib/spack/spack/database.py

@@ -419,14 +419,25 @@ class FailureTracker:
     the likelihood of collision very low with no cleanup required.
     """
 
+    #: root directory of the failure tracker
+    dir: pathlib.Path
+
+    #: File for locking particular concrete spec hashes
+    locker: SpecLocker
+
     def __init__(self, root_dir: Union[str, pathlib.Path], default_timeout: Optional[float]):
         #: Ensure a persistent location for dealing with parallel installation
         #: failures (e.g., across near-concurrent processes).
         self.dir = pathlib.Path(root_dir) / _DB_DIRNAME / "failures"
-        self.dir.mkdir(parents=True, exist_ok=True)
-
         self.locker = SpecLocker(failures_lock_path(root_dir), default_timeout=default_timeout)
 
+    def _ensure_parent_directories(self) -> None:
+        """Ensure that parent directories of the FailureTracker exist.
+
+        Accesses the filesystem only once, the first time it's called on a given FailureTracker.
+        """
+        self.dir.mkdir(parents=True, exist_ok=True)
+
     def clear(self, spec: "spack.spec.Spec", force: bool = False) -> None:
         """Removes any persistent and cached failure tracking for the spec.
 
@@ -469,13 +480,18 @@ def clear_all(self) -> None:
 
         tty.debug("Removing prefix failure tracking files")
         try:
-            for fail_mark in os.listdir(str(self.dir)):
-                try:
-                    (self.dir / fail_mark).unlink()
-                except OSError as exc:
-                    tty.warn(f"Unable to remove failure marking file {fail_mark}: {str(exc)}")
+            marks = os.listdir(str(self.dir))
+        except FileNotFoundError:
+            return  # directory doesn't exist yet
         except OSError as exc:
             tty.warn(f"Unable to remove failure marking files: {str(exc)}")
+            return
+
+        for fail_mark in marks:
+            try:
+                (self.dir / fail_mark).unlink()
+            except OSError as exc:
+                tty.warn(f"Unable to remove failure marking file {fail_mark}: {str(exc)}")
 
     def mark(self, spec: "spack.spec.Spec") -> lk.Lock:
         """Marks a spec as failing to install.
@@ -483,6 +499,8 @@ def mark(self, spec: "spack.spec.Spec") -> lk.Lock:
         Args:
             spec: spec that failed to install
         """
+        self._ensure_parent_directories()
+
         # Dump the spec to the failure file for (manual) debugging purposes
         path = self._path(spec)
         path.write_text(spec.to_json())
@@ -567,17 +585,13 @@ def __init__(
                 Relevant only if the repository is not an upstream.
         """
         self.root = root
-        self.database_directory = os.path.join(self.root, _DB_DIRNAME)
+        self.database_directory = pathlib.Path(self.root) / _DB_DIRNAME
         self.layout = layout
 
         # Set up layout of database files within the db dir
-        self._index_path = os.path.join(self.database_directory, "index.json")
-        self._verifier_path = os.path.join(self.database_directory, "index_verifier")
-        self._lock_path = os.path.join(self.database_directory, "lock")
-
-        # Create needed directories and files
-        if not is_upstream and not os.path.exists(self.database_directory):
-            fs.mkdirp(self.database_directory)
+        self._index_path = self.database_directory / "index.json"
+        self._verifier_path = self.database_directory / "index_verifier"
+        self._lock_path = self.database_directory / "lock"
 
         self.is_upstream = is_upstream
         self.last_seen_verifier = ""
@@ -599,7 +613,7 @@ def __init__(
             self.lock = ForbiddenLock()
         else:
             self.lock = lk.Lock(
-                self._lock_path,
+                str(self._lock_path),
                 default_timeout=self.db_lock_timeout,
                 desc="database",
                 enable=lock_cfg.enable,
@@ -616,6 +630,11 @@ def __init__(
         self._write_transaction_impl = lk.WriteTransaction
         self._read_transaction_impl = lk.ReadTransaction
 
+    def _ensure_parent_directories(self):
+        """Create the parent directory for the DB, if necessary."""
+        if not self.is_upstream:
+            self.database_directory.mkdir(parents=True, exist_ok=True)
+
     def write_transaction(self):
         """Get a write lock context manager for use in a `with` block."""
         return self._write_transaction_impl(self.lock, acquire=self._read, release=self._write)
@@ -630,6 +649,8 @@ def _write_to_file(self, stream):
 
         This function does not do any locking or transactions.
         """
+        self._ensure_parent_directories()
+
         # map from per-spec hash code to installation record.
         installs = dict(
             (k, v.to_dict(include_fields=self.record_fields)) for k, v in self._data.items()
@@ -759,7 +780,7 @@ def _read_from_file(self, filename):
         Does not do any locking.
         """
         try:
-            with open(filename, "r", encoding="utf-8") as f:
+            with open(str(filename), "r", encoding="utf-8") as f:
                 # In the future we may use a stream of JSON objects, hence `raw_decode` for compat.
                 fdata, _ = JSONDecoder().raw_decode(f.read())
         except Exception as e:
@@ -860,11 +881,13 @@ def reindex(self):
         if self.is_upstream:
             raise UpstreamDatabaseLockingError("Cannot reindex an upstream database")
 
+        self._ensure_parent_directories()
+
         # Special transaction to avoid recursive reindex calls and to
         # ignore errors if we need to rebuild a corrupt database.
         def _read_suppress_error():
             try:
-                if os.path.isfile(self._index_path):
+                if self._index_path.is_file():
                     self._read_from_file(self._index_path)
             except CorruptDatabaseError as e:
                 tty.warn(f"Reindexing corrupt database, error was: {e}")
@@ -1007,7 +1030,7 @@ def _check_ref_counts(self):
                     % (key, found, expected, self._index_path)
                 )
 
-    def _write(self, type, value, traceback):
+    def _write(self, type=None, value=None, traceback=None):
         """Write the in-memory database index to its file path.
 
         This is a helper function called by the WriteTransaction context
@@ -1018,6 +1041,8 @@ def _write(self, type, value, traceback):
 
         This routine does no locking.
         """
+        self._ensure_parent_directories()
+
         # Do not write if exceptions were raised
         if type is not None:
             # A failure interrupted a transaction, so we should record that
@@ -1026,16 +1051,16 @@ def _write(self, type, value, traceback):
             self._state_is_inconsistent = True
             return
 
-        temp_file = self._index_path + (".%s.%s.temp" % (_getfqdn(), os.getpid()))
+        temp_file = str(self._index_path) + (".%s.%s.temp" % (_getfqdn(), os.getpid()))
 
         # Write a temporary database file them move it into place
         try:
             with open(temp_file, "w", encoding="utf-8") as f:
                 self._write_to_file(f)
-            fs.rename(temp_file, self._index_path)
+            fs.rename(temp_file, str(self._index_path))
 
             if _use_uuid:
-                with open(self._verifier_path, "w", encoding="utf-8") as f:
+                with self._verifier_path.open("w", encoding="utf-8") as f:
                     new_verifier = str(uuid.uuid4())
                     f.write(new_verifier)
                     self.last_seen_verifier = new_verifier
@@ -1048,11 +1073,11 @@ def _write(self, type, value, traceback):
 
     def _read(self):
         """Re-read Database from the data in the set location. This does no locking."""
-        if os.path.isfile(self._index_path):
+        if self._index_path.is_file():
             current_verifier = ""
             if _use_uuid:
                 try:
-                    with open(self._verifier_path, "r", encoding="utf-8") as f:
+                    with self._verifier_path.open("r", encoding="utf-8") as f:
                         current_verifier = f.read()
                 except BaseException:
                     pass
@@ -1330,7 +1355,7 @@ def deprecate(self, spec: "spack.spec.Spec", deprecator: "spack.spec.Spec") -> N
     def installed_relatives(
         self,
         spec: "spack.spec.Spec",
-        direction: str = "children",
+        direction: tr.DirectionType = "children",
         transitive: bool = True,
         deptype: Union[dt.DepFlag, dt.DepTypes] = dt.ALL,
     ) -> Set["spack.spec.Spec"]:
@@ -1681,7 +1706,7 @@ def query(
             )
 
         results = list(local_results) + list(x for x in upstream_results if x not in local_results)
-        results.sort()
+        results.sort()  # type: ignore[call-overload]
         return results
 
     def query_one(

lib/spack/spack/directory_layout.py

@@ -8,7 +8,7 @@
 import shutil
 import sys
 from pathlib import Path
-from typing import List, Optional, Tuple
+from typing import Dict, List, Optional, Tuple
 
 import llnl.util.filesystem as fs
 from llnl.util.symlink import readlink
@@ -17,7 +17,6 @@
 import spack.hash_types as ht
 import spack.projections
 import spack.spec
-import spack.store
 import spack.util.spack_json as sjson
 from spack.error import SpackError
 
@@ -69,10 +68,9 @@ def specs_from_metadata_dirs(root: str) -> List["spack.spec.Spec"]:
 
 
 class DirectoryLayout:
-    """A directory layout is used to associate unique paths with specs.
-    Different installations are going to want different layouts for their
-    install, and they can use this to customize the nesting structure of
-    spack installs. The default layout is:
+    """A directory layout is used to associate unique paths with specs. Different installations are
+    going to want different layouts for their install, and they can use this to customize the
+    nesting structure of spack installs. The default layout is:
 
     * <install root>/
 
@@ -82,35 +80,30 @@ class DirectoryLayout:
 
           * <name>-<version>-<hash>
 
-    The hash here is a SHA-1 hash for the full DAG plus the build
-    spec.
+    The installation directory projections can be modified with the projections argument."""
 
-    The installation directory projections can be modified with the
-    projections argument.
-    """
-
-    def __init__(self, root, **kwargs):
+    def __init__(
+        self,
+        root,
+        *,
+        projections: Optional[Dict[str, str]] = None,
+        hash_length: Optional[int] = None,
+    ) -> None:
         self.root = root
-        self.check_upstream = True
-        projections = kwargs.get("projections") or default_projections
-        self.projections = dict(
-            (key, projection.lower()) for key, projection in projections.items()
-        )
+        projections = projections or default_projections
+        self.projections = {key: projection.lower() for key, projection in projections.items()}
 
         # apply hash length as appropriate
-        self.hash_length = kwargs.get("hash_length", None)
+        self.hash_length = hash_length
         if self.hash_length is not None:
             for when_spec, projection in self.projections.items():
                 if "{hash}" not in projection:
-                    if "{hash" in projection:
-                        raise InvalidDirectoryLayoutParametersError(
-                            "Conflicting options for installation layout hash" " length"
-                        )
-                    else:
-                        raise InvalidDirectoryLayoutParametersError(
-                            "Cannot specify hash length when the hash is not"
-                            " part of all install_tree projections"
-                        )
+                    raise InvalidDirectoryLayoutParametersError(
+                        "Conflicting options for installation layout hash length"
+                        if "{hash" in projection
+                        else "Cannot specify hash length when the hash is not part of all "
+                        "install_tree projections"
+                    )
                 self.projections[when_spec] = projection.replace(
                     "{hash}", "{hash:%d}" % self.hash_length
                 )
@@ -279,13 +272,6 @@ def path_for_spec(self, spec):
 
         if spec.external:
             return spec.external_path
-        if self.check_upstream:
-            upstream, record = spack.store.STORE.db.query_by_spec_hash(spec.dag_hash())
-            if upstream:
-                raise SpackError(
-                    "Internal error: attempted to call path_for_spec on"
-                    " upstream-installed package."
-                )
 
         path = self.relative_path_for_spec(spec)
         assert not path.startswith(self.root)

lib/spack/spack/error.py

@@ -15,6 +15,10 @@
 SHOW_BACKTRACE = False
 
 
+class SpackAPIWarning(UserWarning):
+    """Warning that formats with file and line number."""
+
+
 class SpackError(Exception):
     """This is the superclass for all Spack errors.
     Subclasses can be found in the modules they have to do with.

lib/spack/spack/filesystem_view.py

@@ -35,7 +35,6 @@
 
 import spack.config
 import spack.directory_layout
-import spack.paths
 import spack.projections
 import spack.relocate
 import spack.schema.projections
@@ -44,7 +43,6 @@
 import spack.util.spack_json as s_json
 import spack.util.spack_yaml as s_yaml
 from spack.error import SpackError
-from spack.hooks import sbang
 
 __all__ = ["FilesystemView", "YamlFilesystemView"]
 
@@ -94,12 +92,6 @@ def view_copy(
         spack.relocate.relocate_text_bin(binaries=[dst], prefixes=prefix_to_projection)
     else:
         prefix_to_projection[spack.store.STORE.layout.root] = view._root
-
-        # This is vestigial code for the *old* location of sbang.
-        prefix_to_projection[f"#!/bin/bash {spack.paths.spack_root}/bin/sbang"] = (
-            sbang.sbang_shebang_line()
-        )
-
         spack.relocate.relocate_text(files=[dst], prefixes=prefix_to_projection)
 
     # The os module on Windows does not have a chown function.

lib/spack/spack/installer.py

@@ -275,7 +275,7 @@ def _do_fake_install(pkg: "spack.package_base.PackageBase") -> None:
     fs.mkdirp(pkg.prefix.bin)
     fs.touch(os.path.join(pkg.prefix.bin, command))
     if sys.platform != "win32":
-        chmod = which("chmod")
+        chmod = which("chmod", required=True)
         chmod("+x", os.path.join(pkg.prefix.bin, command))
 
     # Install fake header file
@@ -539,7 +539,7 @@ def dump_packages(spec: "spack.spec.Spec", path: str) -> None:
     # Note that we copy them in as they are in the *install* directory
     # NOT as they are in the repository, because we want a snapshot of
     # how *this* particular build was done.
-    for node in spec.traverse(deptype=all):
+    for node in spec.traverse(deptype="all"):
         if node is not spec:
             # Locate the dependency package in the install tree and find
             # its provenance information.

lib/spack/spack/main.py

@@ -503,16 +503,16 @@ def make_argument_parser(**kwargs):
     return parser
 
 
-def send_warning_to_tty(message, *args):
+def showwarning(message, category, filename, lineno, file=None, line=None):
     """Redirects messages to tty.warn."""
-    tty.warn(message)
+    if category is spack.error.SpackAPIWarning:
+        tty.warn(f"{filename}:{lineno}: {message}")
+    else:
+        tty.warn(message)
 
 
 def setup_main_options(args):
     """Configure spack globals based on the basic options."""
-    # Assign a custom function to show warnings
-    warnings.showwarning = send_warning_to_tty
-
     # Set up environment based on args.
     tty.set_verbose(args.verbose)
     tty.set_debug(args.debug)
@@ -903,9 +903,10 @@ def _main(argv=None):
     # main() is tricky to get right, so be careful where you put things.
     #
     # Things in this first part of `main()` should *not* require any
-    # configuration. This doesn't include much -- setting up th parser,
+    # configuration. This doesn't include much -- setting up the parser,
     # restoring some key environment variables, very simple CLI options, etc.
     # ------------------------------------------------------------------------
+    warnings.showwarning = showwarning
 
     # Create a parser with a simple positional argument first.  We'll
     # lazily load the subcommand(s) we need later. This allows us to

lib/spack/spack/package.py

@@ -106,8 +106,16 @@
 from spack.variant import any_combination_of, auto_or_any_combination_of, disjoint_sets
 from spack.version import Version, ver
 
-# These are just here for editor support; they will be replaced when the build env
-# is set up.
-make = MakeExecutable("make", jobs=1)
-ninja = MakeExecutable("ninja", jobs=1)
-configure = Executable(join_path(".", "configure"))
+# These are just here for editor support; they may be set when the build env is set up.
+configure: Executable
+make_jobs: int
+make: MakeExecutable
+ninja: MakeExecutable
+python_include: str
+python_platlib: str
+python_purelib: str
+python: Executable
+spack_cc: str
+spack_cxx: str
+spack_f77: str
+spack_fc: str

lib/spack/spack/package_base.py

@@ -767,6 +767,9 @@ def __init__(self, spec):
         self.win_rpath = fsys.WindowsSimulatedRPath(self)
         super().__init__()
 
+    def __getitem__(self, key: str) -> "PackageBase":
+        return self.spec[key].package
+
     @classmethod
     def dependency_names(cls):
         return _subkeys(cls.dependencies)
@@ -1816,12 +1819,6 @@ def _has_make_target(self, target):
         Returns:
             bool: True if 'target' is found, else False
         """
-        # Prevent altering LC_ALL for 'make' outside this function
-        make = copy.deepcopy(self.module.make)
-
-        # Use English locale for missing target message comparison
-        make.add_default_env("LC_ALL", "C")
-
         # Check if we have a Makefile
         for makefile in ["GNUmakefile", "Makefile", "makefile"]:
             if os.path.exists(makefile):
@@ -1830,6 +1827,12 @@ def _has_make_target(self, target):
             tty.debug("No Makefile found in the build directory")
             return False
 
+        # Prevent altering LC_ALL for 'make' outside this function
+        make = copy.deepcopy(self.module.make)
+
+        # Use English locale for missing target message comparison
+        make.add_default_env("LC_ALL", "C")
+
         # Check if 'target' is a valid target.
         #
         # `make -n target` performs a "dry run". It prints the commands that

lib/spack/spack/relocate.py

@@ -54,144 +54,11 @@ def _patchelf() -> Optional[executable.Executable]:
         return spack.bootstrap.ensure_patchelf_in_path_or_raise()
 
 
-def _elf_rpaths_for(path):
-    """Return the RPATHs for an executable or a library.
-
-    Args:
-        path (str): full path to the executable or library
-
-    Return:
-        RPATHs as a list of strings. Returns an empty array
-        on ELF parsing errors, or when the ELF file simply
-        has no rpaths.
-    """
-    return elf.get_rpaths(path) or []
-
-
-def _make_relative(reference_file, path_root, paths):
-    """Return a list where any path in ``paths`` that starts with
-    ``path_root`` is made relative to the directory in which the
-    reference file is stored.
-
-    After a path is made relative it is prefixed with the ``$ORIGIN``
-    string.
-
-    Args:
-        reference_file (str): file from which the reference directory
-            is computed
-        path_root (str): root of the relative paths
-        paths: (list) paths to be examined
-
-    Returns:
-        List of relative paths
-    """
-    start_directory = os.path.dirname(reference_file)
-    pattern = re.compile(path_root)
-    relative_paths = []
-
-    for path in paths:
-        if pattern.match(path):
-            rel = os.path.relpath(path, start=start_directory)
-            path = os.path.join("$ORIGIN", rel)
-
-        relative_paths.append(path)
-
-    return relative_paths
-
-
-def _normalize_relative_paths(start_path, relative_paths):
-    """Normalize the relative paths with respect to the original path name
-    of the file (``start_path``).
-
-    The paths that are passed to this function existed or were relevant
-    on another filesystem, so os.path.abspath cannot be used.
-
-    A relative path may contain the signifier $ORIGIN. Assuming that
-    ``start_path`` is absolute, this implies that the relative path
-    (relative to start_path) should be replaced with an absolute path.
-
-    Args:
-        start_path (str): path from which the starting directory
-            is extracted
-        relative_paths (str): list of relative paths as obtained by a
-            call to :ref:`_make_relative`
-
-    Returns:
-        List of normalized paths
-    """
-    normalized_paths = []
-    pattern = re.compile(re.escape("$ORIGIN"))
-    start_directory = os.path.dirname(start_path)
-
-    for path in relative_paths:
-        if path.startswith("$ORIGIN"):
-            sub = pattern.sub(start_directory, path)
-            path = os.path.normpath(sub)
-        normalized_paths.append(path)
-
-    return normalized_paths
-
-
 def _decode_macho_data(bytestring):
     return bytestring.rstrip(b"\x00").decode("ascii")
 
 
-def macho_make_paths_relative(path_name, old_layout_root, rpaths, deps, idpath):
-    """
-    Return a dictionary mapping the original rpaths to the relativized rpaths.
-    This dictionary is used to replace paths in mach-o binaries.
-    Replace old_dir with relative path from dirname of path name
-    in rpaths and deps; idpath is replaced with @rpath/libname.
-    """
-    paths_to_paths = dict()
-    if idpath:
-        paths_to_paths[idpath] = os.path.join("@rpath", "%s" % os.path.basename(idpath))
-    for rpath in rpaths:
-        if re.match(old_layout_root, rpath):
-            rel = os.path.relpath(rpath, start=os.path.dirname(path_name))
-            paths_to_paths[rpath] = os.path.join("@loader_path", "%s" % rel)
-        else:
-            paths_to_paths[rpath] = rpath
-    for dep in deps:
-        if re.match(old_layout_root, dep):
-            rel = os.path.relpath(dep, start=os.path.dirname(path_name))
-            paths_to_paths[dep] = os.path.join("@loader_path", "%s" % rel)
-        else:
-            paths_to_paths[dep] = dep
-    return paths_to_paths
-
-
-def macho_make_paths_normal(orig_path_name, rpaths, deps, idpath):
-    """
-    Return a dictionary mapping the relativized rpaths to the original rpaths.
-    This dictionary is used to replace paths in mach-o binaries.
-    Replace '@loader_path' with the dirname of the origname path name
-    in rpaths and deps; idpath is replaced with the original path name
-    """
-    rel_to_orig = dict()
-    if idpath:
-        rel_to_orig[idpath] = orig_path_name
-
-    for rpath in rpaths:
-        if re.match("@loader_path", rpath):
-            norm = os.path.normpath(
-                re.sub(re.escape("@loader_path"), os.path.dirname(orig_path_name), rpath)
-            )
-            rel_to_orig[rpath] = norm
-        else:
-            rel_to_orig[rpath] = rpath
-    for dep in deps:
-        if re.match("@loader_path", dep):
-            norm = os.path.normpath(
-                re.sub(re.escape("@loader_path"), os.path.dirname(orig_path_name), dep)
-            )
-            rel_to_orig[dep] = norm
-        else:
-            rel_to_orig[dep] = dep
-    return rel_to_orig
-
-
-def macho_find_paths(orig_rpaths, deps, idpath, old_layout_root, prefix_to_prefix):
+def macho_find_paths(orig_rpaths, deps, idpath, prefix_to_prefix):
     """
     Inputs
     original rpaths from mach-o binaries
@@ -207,13 +74,12 @@ def macho_find_paths(orig_rpaths, deps, idpath, old_layout_root, prefix_to_prefi
     # Sort from longest path to shortest, to ensure we try /foo/bar/baz before /foo/bar
     prefix_iteration_order = sorted(prefix_to_prefix, key=len, reverse=True)
     for orig_rpath in orig_rpaths:
-        if orig_rpath.startswith(old_layout_root):
-            for old_prefix in prefix_iteration_order:
-                new_prefix = prefix_to_prefix[old_prefix]
-                if orig_rpath.startswith(old_prefix):
-                    new_rpath = re.sub(re.escape(old_prefix), new_prefix, orig_rpath)
-                    paths_to_paths[orig_rpath] = new_rpath
-                    break
+        for old_prefix in prefix_iteration_order:
+            new_prefix = prefix_to_prefix[old_prefix]
+            if orig_rpath.startswith(old_prefix):
+                new_rpath = re.sub(re.escape(old_prefix), new_prefix, orig_rpath)
+                paths_to_paths[orig_rpath] = new_rpath
+                break
         else:
             paths_to_paths[orig_rpath] = orig_rpath
 
@@ -348,9 +214,7 @@ def _set_elf_rpaths_and_interpreter(
         return None
 
 
-def relocate_macho_binaries(
-    path_names, old_layout_root, new_layout_root, prefix_to_prefix, rel, old_prefix, new_prefix
-):
+def relocate_macho_binaries(path_names, prefix_to_prefix):
     """
     Use macholib python package to get the rpaths, depedent libraries
     and library identity for libraries from the MachO object. Modify them
@@ -363,77 +227,15 @@ def relocate_macho_binaries(
         # Corner case where macho object file ended up in the path name list
         if path_name.endswith(".o"):
             continue
-        if rel:
-            # get the relativized paths
-            rpaths, deps, idpath = macholib_get_paths(path_name)
-            # get the file path name in the original prefix
-            orig_path_name = re.sub(re.escape(new_prefix), old_prefix, path_name)
-            # get the mapping of the relativized paths to the original
-            # normalized paths
-            rel_to_orig = macho_make_paths_normal(orig_path_name, rpaths, deps, idpath)
-            # replace the relativized paths with normalized paths
-            modify_macho_object(path_name, rpaths, deps, idpath, rel_to_orig)
-            # get the normalized paths in the mach-o binary
-            rpaths, deps, idpath = macholib_get_paths(path_name)
-            # get the mapping of paths in old prefix to path in new prefix
-            paths_to_paths = macho_find_paths(
-                rpaths, deps, idpath, old_layout_root, prefix_to_prefix
-            )
-            # replace the old paths with new paths
-            modify_macho_object(path_name, rpaths, deps, idpath, paths_to_paths)
-            # get the new normalized path in the mach-o binary
-            rpaths, deps, idpath = macholib_get_paths(path_name)
-            # get the mapping of paths to relative paths in the new prefix
-            paths_to_paths = macho_make_paths_relative(
-                path_name, new_layout_root, rpaths, deps, idpath
-            )
-            # replace the new paths with relativized paths in the new prefix
-            modify_macho_object(path_name, rpaths, deps, idpath, paths_to_paths)
-        else:
-            # get the paths in the old prefix
-            rpaths, deps, idpath = macholib_get_paths(path_name)
-            # get the mapping of paths in the old prerix to the new prefix
-            paths_to_paths = macho_find_paths(
-                rpaths, deps, idpath, old_layout_root, prefix_to_prefix
-            )
-            # replace the old paths with new paths
-            modify_macho_object(path_name, rpaths, deps, idpath, paths_to_paths)
+        # get the paths in the old prefix
+        rpaths, deps, idpath = macholib_get_paths(path_name)
+        # get the mapping of paths in the old prerix to the new prefix
+        paths_to_paths = macho_find_paths(rpaths, deps, idpath, prefix_to_prefix)
+        # replace the old paths with new paths
+        modify_macho_object(path_name, rpaths, deps, idpath, paths_to_paths)
 
 
-def _transform_rpaths(orig_rpaths, orig_root, new_prefixes):
-    """Return an updated list of RPATHs where each entry in the original list
-    starting with the old root is relocated to another place according to the
-    mapping passed as argument.
-
-    Args:
-        orig_rpaths (list): list of the original RPATHs
-        orig_root (str): original root to be substituted
-        new_prefixes (dict): dictionary that maps the original prefixes to
-            where they should be relocated
-
-    Returns:
-        List of paths
-    """
-    new_rpaths = []
-    for orig_rpath in orig_rpaths:
-        # If the original RPATH doesn't start with the target root
-        # append it verbatim and proceed
-        if not orig_rpath.startswith(orig_root):
-            new_rpaths.append(orig_rpath)
-            continue
-
-        # Otherwise inspect the mapping and transform + append any prefix
-        # that starts with a registered key
-        # avoiding duplicates
-        for old_prefix, new_prefix in new_prefixes.items():
-            if orig_rpath.startswith(old_prefix):
-                new_rpath = re.sub(re.escape(old_prefix), new_prefix, orig_rpath)
-                if new_rpath not in new_rpaths:
-                    new_rpaths.append(new_rpath)
-    return new_rpaths
-
-
-def new_relocate_elf_binaries(binaries, prefix_to_prefix):
+def relocate_elf_binaries(binaries, prefix_to_prefix):
     """Take a list of binaries, and an ordered dictionary of
     prefix to prefix mapping, and update the rpaths accordingly."""
 
@@ -452,98 +254,6 @@ def new_relocate_elf_binaries(binaries, prefix_to_prefix):
             _set_elf_rpaths_and_interpreter(path, rpaths=rpaths, interpreter=interpreter)
 
 
-def relocate_elf_binaries(
-    binaries, orig_root, new_root, new_prefixes, rel, orig_prefix, new_prefix
-):
-    """Relocate the binaries passed as arguments by changing their RPATHs.
-
-    Use patchelf to get the original RPATHs and then replace them with
-    rpaths in the new directory layout.
-
-    New RPATHs are determined from a dictionary mapping the prefixes in the
-    old directory layout to the prefixes in the new directory layout if the
-    rpath was in the old layout root, i.e. system paths are not replaced.
-
-    Args:
-        binaries (list): list of binaries that might need relocation, located
-            in the new prefix
-        orig_root (str): original root to be substituted
-        new_root (str): new root to be used, only relevant for relative RPATHs
-        new_prefixes (dict): dictionary that maps the original prefixes to
-            where they should be relocated
-        rel (bool): True if the RPATHs are relative, False if they are absolute
-        orig_prefix (str): prefix where the executable was originally located
-        new_prefix (str): prefix where we want to relocate the executable
-    """
-    for new_binary in binaries:
-        orig_rpaths = _elf_rpaths_for(new_binary)
-        # TODO: Can we deduce `rel` from the original RPATHs?
-        if rel:
-            # Get the file path in the original prefix
-            orig_binary = re.sub(re.escape(new_prefix), orig_prefix, new_binary)
-
-            # Get the normalized RPATHs in the old prefix using the file path
-            # in the orig prefix
-            orig_norm_rpaths = _normalize_relative_paths(orig_binary, orig_rpaths)
-            # Get the normalize RPATHs in the new prefix
-            new_norm_rpaths = _transform_rpaths(orig_norm_rpaths, orig_root, new_prefixes)
-            # Get the relative RPATHs in the new prefix
-            new_rpaths = _make_relative(new_binary, new_root, new_norm_rpaths)
-            # check to see if relative rpaths are changed before rewriting
-            if sorted(new_rpaths) != sorted(orig_rpaths):
-                _set_elf_rpaths_and_interpreter(new_binary, new_rpaths)
-        else:
-            new_rpaths = _transform_rpaths(orig_rpaths, orig_root, new_prefixes)
-            _set_elf_rpaths_and_interpreter(new_binary, new_rpaths)
-
-
-def make_link_relative(new_links, orig_links):
-    """Compute the relative target from the original link and
-    make the new link relative.
-
-    Args:
-        new_links (list): new links to be made relative
-        orig_links (list): original links
-    """
-    for new_link, orig_link in zip(new_links, orig_links):
-        target = readlink(orig_link)
-        relative_target = os.path.relpath(target, os.path.dirname(orig_link))
-        os.unlink(new_link)
-        symlink(relative_target, new_link)
-
-
-def make_macho_binaries_relative(cur_path_names, orig_path_names, old_layout_root):
-    """
-    Replace old RPATHs with paths relative to old_dir in binary files
-    """
-    if not sys.platform == "darwin":
-        return
-
-    for cur_path, orig_path in zip(cur_path_names, orig_path_names):
-        (rpaths, deps, idpath) = macholib_get_paths(cur_path)
-        paths_to_paths = macho_make_paths_relative(
-            orig_path, old_layout_root, rpaths, deps, idpath
-        )
-        modify_macho_object(cur_path, rpaths, deps, idpath, paths_to_paths)
-
-
-def make_elf_binaries_relative(new_binaries, orig_binaries, orig_layout_root):
-    """Replace the original RPATHs in the new binaries making them
-    relative to the original layout root.
-
-    Args:
-        new_binaries (list): new binaries whose RPATHs is to be made relative
-        orig_binaries (list): original binaries
-        orig_layout_root (str): path to be used as a base for making
-            RPATHs relative
-    """
-    for new_binary, orig_binary in zip(new_binaries, orig_binaries):
-        orig_rpaths = _elf_rpaths_for(new_binary)
-        if orig_rpaths:
-            new_rpaths = _make_relative(orig_binary, orig_layout_root, orig_rpaths)
-            _set_elf_rpaths_and_interpreter(new_binary, new_rpaths)
-
-
 def warn_if_link_cant_be_relocated(link, target):
     if not os.path.isabs(target):
         return

lib/spack/spack/relocate_text.py

@@ -208,7 +208,7 @@ def _apply_to_file(self, f):
         # but it's nasty to deal with matches across boundaries, so let's stick to
         # something simple.
 
-        modified = True
+        modified = False
 
         for match in self.regex.finditer(f.read()):
             # The matching prefix (old) and its replacement (new)

lib/spack/spack/rewiring.py

@@ -48,7 +48,7 @@ def rewire_node(spec, explicit):
     # spec
     prefix_to_prefix = {spec.build_spec.prefix: spec.prefix}
     build_spec_ids = set(id(s) for s in spec.build_spec.traverse(deptype=dt.ALL & ~dt.BUILD))
-    for s in bindist.deps_to_relocate(spec):
+    for s in bindist.specs_to_relocate(spec):
         analog = s
         if id(s) not in build_spec_ids:
             analogs = [
@@ -77,25 +77,9 @@ def rewire_node(spec, explicit):
     ]
     if bins_to_relocate:
         if "macho" in platform.binary_formats:
-            relocate.relocate_macho_binaries(
-                bins_to_relocate,
-                str(spack.store.STORE.layout.root),
-                str(spack.store.STORE.layout.root),
-                prefix_to_prefix,
-                False,
-                spec.build_spec.prefix,
-                spec.prefix,
-            )
+            relocate.relocate_macho_binaries(bins_to_relocate, prefix_to_prefix)
         if "elf" in platform.binary_formats:
-            relocate.relocate_elf_binaries(
-                bins_to_relocate,
-                str(spack.store.STORE.layout.root),
-                str(spack.store.STORE.layout.root),
-                prefix_to_prefix,
-                False,
-                spec.build_spec.prefix,
-                spec.prefix,
-            )
+            relocate.relocate_elf_binaries(bins_to_relocate, prefix_to_prefix)
         relocate.relocate_text_bin(binaries=bins_to_relocate, prefixes=prefix_to_prefix)
     shutil.rmtree(tempdir)
     install_manifest = os.path.join(

lib/spack/spack/schema/config.py

@@ -106,10 +106,17 @@
             {
                 "names": ["install_missing_compilers"],
                 "message": "The config:install_missing_compilers option has been deprecated in "
-                "Spack v0.23, and is currently ignored. It will be removed from config after "
+                "Spack v0.23, and is currently ignored. It will be removed from config in "
                 "Spack v1.0.",
                 "error": False,
             },
+            {
+                "names": ["install_path_scheme"],
+                "message": "The config:install_path_scheme option was deprecated in Spack v0.16 "
+                "in favor of config:install_tree:projections:all. It will be removed in Spack "
+                "v1.0.",
+                "error": False,
+            },
         ],
     }
 }

lib/spack/spack/solver/asp.py

@@ -37,6 +37,7 @@
 import spack.package_prefs
 import spack.platforms
 import spack.repo
+import spack.solver.splicing
 import spack.spec
 import spack.store
 import spack.util.crypto
@@ -67,7 +68,7 @@
 
 GitOrStandardVersion = Union[spack.version.GitVersion, spack.version.StandardVersion]
 
-TransformFunction = Callable[["spack.spec.Spec", List[AspFunction]], List[AspFunction]]
+TransformFunction = Callable[[spack.spec.Spec, List[AspFunction]], List[AspFunction]]
 
 #: Enable the addition of a runtime node
 WITH_RUNTIME = sys.platform != "win32"
@@ -127,8 +128,8 @@ def __str__(self):
 
 @contextmanager
 def named_spec(
-    spec: Optional["spack.spec.Spec"], name: Optional[str]
-) -> Iterator[Optional["spack.spec.Spec"]]:
+    spec: Optional[spack.spec.Spec], name: Optional[str]
+) -> Iterator[Optional[spack.spec.Spec]]:
     """Context manager to temporarily set the name of a spec"""
     if spec is None or name is None:
         yield spec
@@ -747,11 +748,11 @@ def on_model(model):
 class KnownCompiler(NamedTuple):
     """Data class to collect information on compilers"""
 
-    spec: "spack.spec.Spec"
+    spec: spack.spec.Spec
     os: str
-    target: str
+    target: Optional[str]
     available: bool
-    compiler_obj: Optional["spack.compiler.Compiler"]
+    compiler_obj: Optional[spack.compiler.Compiler]
 
     def _key(self):
         return self.spec, self.os, self.target
@@ -1132,7 +1133,7 @@ def __init__(self, tests: bool = False):
             set
         )
 
-        self.possible_compilers: List = []
+        self.possible_compilers: List[KnownCompiler] = []
         self.possible_oses: Set = set()
         self.variant_values_from_specs: Set = set()
         self.version_constraints: Set = set()
@@ -1386,7 +1387,7 @@ def effect_rules(self):
 
     def define_variant(
         self,
-        pkg: "Type[spack.package_base.PackageBase]",
+        pkg: Type[spack.package_base.PackageBase],
         name: str,
         when: spack.spec.Spec,
         variant_def: vt.Variant,
@@ -1490,7 +1491,7 @@ def define_auto_variant(self, name: str, multi: bool):
             )
         )
 
-    def variant_rules(self, pkg: "Type[spack.package_base.PackageBase]"):
+    def variant_rules(self, pkg: Type[spack.package_base.PackageBase]):
         for name in pkg.variant_names():
             self.gen.h3(f"Variant {name} in package {pkg.name}")
             for when, variant_def in pkg.variant_definitions(name):
@@ -1681,8 +1682,8 @@ def dependency_holds(input_spec, requirements):
     def _gen_match_variant_splice_constraints(
         self,
         pkg,
-        cond_spec: "spack.spec.Spec",
-        splice_spec: "spack.spec.Spec",
+        cond_spec: spack.spec.Spec,
+        splice_spec: spack.spec.Spec,
         hash_asp_var: "AspVar",
         splice_node,
         match_variants: List[str],
@@ -1740,7 +1741,7 @@ def package_splice_rules(self, pkg):
                     if any(
                         v in cond.variants or v in spec_to_splice.variants for v in match_variants
                     ):
-                        raise Exception(
+                        raise spack.error.PackageError(
                             "Overlap between match_variants and explicitly set variants"
                         )
                     variant_constraints = self._gen_match_variant_splice_constraints(
@@ -2977,7 +2978,7 @@ def _specs_from_requires(self, pkg_name, section):
             for s in spec_group[key]:
                 yield _spec_with_default_name(s, pkg_name)
 
-    def pkg_class(self, pkg_name: str) -> typing.Type["spack.package_base.PackageBase"]:
+    def pkg_class(self, pkg_name: str) -> typing.Type[spack.package_base.PackageBase]:
         request = pkg_name
         if pkg_name in self.explicitly_required_namespaces:
             namespace = self.explicitly_required_namespaces[pkg_name]
@@ -3096,7 +3097,7 @@ def __init__(self, configuration) -> None:
 
             self.compilers.add(candidate)
 
-    def with_input_specs(self, input_specs: List["spack.spec.Spec"]) -> "CompilerParser":
+    def with_input_specs(self, input_specs: List[spack.spec.Spec]) -> "CompilerParser":
         """Accounts for input specs when building the list of possible compilers.
 
         Args:
@@ -3136,7 +3137,7 @@ def with_input_specs(self, input_specs: List["spack.spec.Spec"]) -> "CompilerPar
 
         return self
 
-    def add_compiler_from_concrete_spec(self, spec: "spack.spec.Spec") -> None:
+    def add_compiler_from_concrete_spec(self, spec: spack.spec.Spec) -> None:
         """Account for compilers that are coming from concrete specs, through reuse.
 
         Args:
@@ -3374,14 +3375,6 @@ def consume_facts(self):
         self._setup.effect_rules()
 
 
-# This should be a dataclass, but dataclasses don't work on Python 3.6
-class Splice:
-    def __init__(self, splice_node: NodeArgument, child_name: str, child_hash: str):
-        self.splice_node = splice_node
-        self.child_name = child_name
-        self.child_hash = child_hash
-
-
 class SpecBuilder:
     """Class with actions to rebuild a spec from ASP results."""
 
@@ -3421,7 +3414,7 @@ def __init__(self, specs, hash_lookup=None):
         self._specs: Dict[NodeArgument, spack.spec.Spec] = {}
 
         # Matches parent nodes to splice node
-        self._splices: Dict[NodeArgument, List[Splice]] = {}
+        self._splices: Dict[spack.spec.Spec, List[spack.solver.splicing.Splice]] = {}
         self._result = None
         self._command_line_specs = specs
         self._flag_sources: Dict[Tuple[NodeArgument, str], Set[str]] = collections.defaultdict(
@@ -3540,15 +3533,13 @@ def reorder_flags(self):
         )
         cmd_specs = dict((s.name, s) for spec in self._command_line_specs for s in spec.traverse())
 
-        for spec in self._specs.values():
+        for node, spec in self._specs.items():
             # if bootstrapping, compiler is not in config and has no flags
             flagmap_from_compiler = {}
             if spec.compiler in compilers:
                 flagmap_from_compiler = compilers[spec.compiler].flags
 
             for flag_type in spec.compiler_flags.valid_compiler_flags():
-                node = SpecBuilder.make_node(pkg=spec.name)
-
                 ordered_flags = []
 
                 # 1. Put compiler flags first
@@ -3630,49 +3621,12 @@ def splice_at_hash(
         child_name: str,
         child_hash: str,
     ):
-        splice = Splice(splice_node, child_name=child_name, child_hash=child_hash)
-        self._splices.setdefault(parent_node, []).append(splice)
-
-    def _resolve_automatic_splices(self):
-        """After all of the specs have been concretized, apply all immediate splices.
-
-        Use reverse topological order to ensure that all dependencies are resolved
-        before their parents, allowing for maximal sharing and minimal copying.
-
-        """
-        fixed_specs = {}
-
-        # create a mapping from dag hash to an integer representing position in reverse topo order.
-        specs = self._specs.values()
-        topo_order = list(traverse.traverse_nodes(specs, order="topo", key=traverse.by_dag_hash))
-        topo_lookup = {spec.dag_hash(): index for index, spec in enumerate(reversed(topo_order))}
-
-        # iterate over specs, children before parents
-        for node, spec in sorted(self._specs.items(), key=lambda x: topo_lookup[x[1].dag_hash()]):
-            immediate = self._splices.get(node, [])
-            if not immediate and not any(
-                edge.spec in fixed_specs for edge in spec.edges_to_dependencies()
-            ):
-                continue
-            new_spec = spec.copy(deps=False)
-            new_spec.build_spec = spec
-            for edge in spec.edges_to_dependencies():
-                depflag = edge.depflag & ~dt.BUILD
-                if any(edge.spec.dag_hash() == splice.child_hash for splice in immediate):
-                    splice = [s for s in immediate if s.child_hash == edge.spec.dag_hash()][0]
-                    new_spec.add_dependency_edge(
-                        self._specs[splice.splice_node], depflag=depflag, virtuals=edge.virtuals
-                    )
-                elif edge.spec in fixed_specs:
-                    new_spec.add_dependency_edge(
-                        fixed_specs[edge.spec], depflag=depflag, virtuals=edge.virtuals
-                    )
-                else:
-                    new_spec.add_dependency_edge(
-                        edge.spec, depflag=depflag, virtuals=edge.virtuals
-                    )
-            self._specs[node] = new_spec
-            fixed_specs[spec] = new_spec
+        parent_spec = self._specs[parent_node]
+        splice_spec = self._specs[splice_node]
+        splice = spack.solver.splicing.Splice(
+            splice_spec, child_name=child_name, child_hash=child_hash
+        )
+        self._splices.setdefault(parent_spec, []).append(splice)
 
     @staticmethod
     def sort_fn(function_tuple) -> Tuple[int, int]:
@@ -3765,7 +3719,15 @@ def build_specs(self, function_tuples):
         for root in roots.values():
             root._finalize_concretization()
 
-        self._resolve_automatic_splices()
+        # Only attempt to resolve automatic splices if the solver produced any
+        if self._splices:
+            resolved_splices = spack.solver.splicing._resolve_collected_splices(
+                list(self._specs.values()), self._splices
+            )
+            new_specs = {}
+            for node, spec in self._specs.items():
+                new_specs[node] = resolved_splices.get(spec, spec)
+            self._specs = new_specs
 
         for s in self._specs.values():
             spack.spec.Spec.ensure_no_deprecated(s)

lib/spack/spack/solver/splicing.py

@@ -0,0 +1,73 @@
+# Copyright Spack Project Developers. See COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+from functools import cmp_to_key
+from typing import Dict, List, NamedTuple
+
+import spack.deptypes as dt
+from spack.spec import Spec
+from spack.traverse import by_dag_hash, traverse_nodes
+
+
+class Splice(NamedTuple):
+    #: The spec being spliced into a parent
+    splice_spec: Spec
+    #: The name of the child that splice spec is replacing
+    child_name: str
+    #: The hash of the child that `splice_spec` is replacing
+    child_hash: str
+
+
+def _resolve_collected_splices(
+    specs: List[Spec], splices: Dict[Spec, List[Splice]]
+) -> Dict[Spec, Spec]:
+    """After all of the specs have been concretized, apply all immediate splices.
+    Returns a dict mapping original specs to their resolved counterparts
+    """
+
+    def splice_cmp(s1: Spec, s2: Spec):
+        """This function can be used to sort a list of specs such that that any
+        spec which will be spliced into a parent comes after the parent it will
+        be spliced into. This order ensures that transitive splices will be
+        executed in the correct order.
+        """
+
+        s1_splices = splices.get(s1, [])
+        s2_splices = splices.get(s2, [])
+        if any([s2.dag_hash() == splice.splice_spec.dag_hash() for splice in s1_splices]):
+            return -1
+        elif any([s1.dag_hash() == splice.splice_spec.dag_hash() for splice in s2_splices]):
+            return 1
+        else:
+            return 0
+
+    splice_order = sorted(specs, key=cmp_to_key(splice_cmp))
+    reverse_topo_order = reversed(
+        [x for x in traverse_nodes(splice_order, order="topo", key=by_dag_hash) if x in specs]
+    )
+
+    already_resolved: Dict[Spec, Spec] = {}
+    for spec in reverse_topo_order:
+        immediate = splices.get(spec, [])
+        if not immediate and not any(
+            edge.spec in already_resolved for edge in spec.edges_to_dependencies()
+        ):
+            continue
+        new_spec = spec.copy(deps=False)
+        new_spec.clear_caches(ignore=("package_hash",))
+        new_spec.build_spec = spec
+        for edge in spec.edges_to_dependencies():
+            depflag = edge.depflag & ~dt.BUILD
+            if any(edge.spec.dag_hash() == splice.child_hash for splice in immediate):
+                splice = [s for s in immediate if s.child_hash == edge.spec.dag_hash()][0]
+                # If the spec being splice in is also spliced
+                splice_spec = already_resolved.get(splice.splice_spec, splice.splice_spec)
+                new_spec.add_dependency_edge(splice_spec, depflag=depflag, virtuals=edge.virtuals)
+            elif edge.spec in already_resolved:
+                new_spec.add_dependency_edge(
+                    already_resolved[edge.spec], depflag=depflag, virtuals=edge.virtuals
+                )
+            else:
+                new_spec.add_dependency_edge(edge.spec, depflag=depflag, virtuals=edge.virtuals)
+        already_resolved[spec] = new_spec
+    return already_resolved

lib/spack/spack/spec.py

@@ -58,7 +58,21 @@
 import re
 import socket
 import warnings
-from typing import Any, Callable, Dict, Iterable, List, Match, Optional, Set, Tuple, Union
+from typing import (
+    Any,
+    Callable,
+    Dict,
+    Iterable,
+    List,
+    Match,
+    Optional,
+    Set,
+    Tuple,
+    Union,
+    overload,
+)
+
+from typing_extensions import Literal
 
 import archspec.cpu
 
@@ -72,7 +86,6 @@
 import spack
 import spack.compiler
 import spack.compilers
-import spack.config
 import spack.deptypes as dt
 import spack.error
 import spack.hash_types as ht
@@ -80,10 +93,9 @@
 import spack.platforms
 import spack.provider_index
 import spack.repo
-import spack.solver
 import spack.spec_parser
 import spack.store
-import spack.traverse as traverse
+import spack.traverse
 import spack.util.executable
 import spack.util.hash
 import spack.util.module_cmd as md
@@ -1339,16 +1351,16 @@ def tree(
     depth: bool = False,
     hashes: bool = False,
     hashlen: Optional[int] = None,
-    cover: str = "nodes",
+    cover: spack.traverse.CoverType = "nodes",
     indent: int = 0,
     format: str = DEFAULT_FORMAT,
-    deptypes: Union[Tuple[str, ...], str] = "all",
+    deptypes: Union[dt.DepFlag, dt.DepTypes] = dt.ALL,
     show_types: bool = False,
     depth_first: bool = False,
     recurse_dependencies: bool = True,
     status_fn: Optional[Callable[["Spec"], InstallStatus]] = None,
     prefix: Optional[Callable[["Spec"], str]] = None,
-    key=id,
+    key: Callable[["Spec"], Any] = id,
 ) -> str:
     """Prints out specs and their dependencies, tree-formatted with indentation.
 
@@ -1380,11 +1392,16 @@ def tree(
     # reduce deptypes over all in-edges when covering nodes
     if show_types and cover == "nodes":
         deptype_lookup: Dict[str, dt.DepFlag] = collections.defaultdict(dt.DepFlag)
-        for edge in traverse.traverse_edges(specs, cover="edges", deptype=deptypes, root=False):
+        for edge in spack.traverse.traverse_edges(
+            specs, cover="edges", deptype=deptypes, root=False
+        ):
             deptype_lookup[edge.spec.dag_hash()] |= edge.depflag
 
-    for d, dep_spec in traverse.traverse_tree(
-        sorted(specs), cover=cover, deptype=deptypes, depth_first=depth_first, key=key
+    # SupportsRichComparisonT issue with List[Spec]
+    sorted_specs: List["Spec"] = sorted(specs)  # type: ignore[type-var]
+
+    for d, dep_spec in spack.traverse.traverse_tree(
+        sorted_specs, cover=cover, deptype=deptypes, depth_first=depth_first, key=key
     ):
         node = dep_spec.spec
 
@@ -1927,13 +1944,125 @@ def installed_upstream(self):
         upstream, _ = spack.store.STORE.db.query_by_spec_hash(self.dag_hash())
         return upstream
 
-    def traverse(self, **kwargs):
-        """Shorthand for :meth:`~spack.traverse.traverse_nodes`"""
-        return traverse.traverse_nodes([self], **kwargs)
+    @overload
+    def traverse(
+        self,
+        *,
+        root: bool = ...,
+        order: spack.traverse.OrderType = ...,
+        cover: spack.traverse.CoverType = ...,
+        direction: spack.traverse.DirectionType = ...,
+        deptype: Union[dt.DepFlag, dt.DepTypes] = ...,
+        depth: Literal[False] = False,
+        key: Callable[["Spec"], Any] = ...,
+        visited: Optional[Set[Any]] = ...,
+    ) -> Iterable["Spec"]: ...
 
-    def traverse_edges(self, **kwargs):
+    @overload
+    def traverse(
+        self,
+        *,
+        root: bool = ...,
+        order: spack.traverse.OrderType = ...,
+        cover: spack.traverse.CoverType = ...,
+        direction: spack.traverse.DirectionType = ...,
+        deptype: Union[dt.DepFlag, dt.DepTypes] = ...,
+        depth: Literal[True],
+        key: Callable[["Spec"], Any] = ...,
+        visited: Optional[Set[Any]] = ...,
+    ) -> Iterable[Tuple[int, "Spec"]]: ...
+
+    def traverse(
+        self,
+        *,
+        root: bool = True,
+        order: spack.traverse.OrderType = "pre",
+        cover: spack.traverse.CoverType = "nodes",
+        direction: spack.traverse.DirectionType = "children",
+        deptype: Union[dt.DepFlag, dt.DepTypes] = "all",
+        depth: bool = False,
+        key: Callable[["Spec"], Any] = id,
+        visited: Optional[Set[Any]] = None,
+    ) -> Iterable[Union["Spec", Tuple[int, "Spec"]]]:
+        """Shorthand for :meth:`~spack.traverse.traverse_nodes`"""
+        return spack.traverse.traverse_nodes(
+            [self],
+            root=root,
+            order=order,
+            cover=cover,
+            direction=direction,
+            deptype=deptype,
+            depth=depth,
+            key=key,
+            visited=visited,
+        )
+
+    @overload
+    def traverse_edges(
+        self,
+        *,
+        root: bool = ...,
+        order: spack.traverse.OrderType = ...,
+        cover: spack.traverse.CoverType = ...,
+        direction: spack.traverse.DirectionType = ...,
+        deptype: Union[dt.DepFlag, dt.DepTypes] = ...,
+        depth: Literal[False] = False,
+        key: Callable[["Spec"], Any] = ...,
+        visited: Optional[Set[Any]] = ...,
+    ) -> Iterable[DependencySpec]: ...
+
+    @overload
+    def traverse_edges(
+        self,
+        *,
+        root: bool = ...,
+        order: spack.traverse.OrderType = ...,
+        cover: spack.traverse.CoverType = ...,
+        direction: spack.traverse.DirectionType = ...,
+        deptype: Union[dt.DepFlag, dt.DepTypes] = ...,
+        depth: Literal[True],
+        key: Callable[["Spec"], Any] = ...,
+        visited: Optional[Set[Any]] = ...,
+    ) -> Iterable[Tuple[int, DependencySpec]]: ...
+
+    def traverse_edges(
+        self,
+        *,
+        root: bool = True,
+        order: spack.traverse.OrderType = "pre",
+        cover: spack.traverse.CoverType = "nodes",
+        direction: spack.traverse.DirectionType = "children",
+        deptype: Union[dt.DepFlag, dt.DepTypes] = "all",
+        depth: bool = False,
+        key: Callable[["Spec"], Any] = id,
+        visited: Optional[Set[Any]] = None,
+    ) -> Iterable[Union[DependencySpec, Tuple[int, DependencySpec]]]:
         """Shorthand for :meth:`~spack.traverse.traverse_edges`"""
-        return traverse.traverse_edges([self], **kwargs)
+        return spack.traverse.traverse_edges(
+            [self],
+            root=root,
+            order=order,
+            cover=cover,
+            direction=direction,
+            deptype=deptype,
+            depth=depth,
+            key=key,
+            visited=visited,
+        )
+
+    @property
+    def long_spec(self):
+        """Returns a string of the spec with the dependencies completely
+        enumerated."""
+        root_str = [self.format()]
+        sorted_dependencies = sorted(
+            self.traverse(root=False), key=lambda x: (x.name, x.abstract_hash)
+        )
+        sorted_dependencies = [
+            d.format("{edge_attributes} " + DEFAULT_FORMAT) for d in sorted_dependencies
+        ]
+        spec_str = " ^".join(root_str + sorted_dependencies)
+        return spec_str.strip()
 
     @property
     def short_spec(self):
@@ -2203,11 +2332,16 @@ def to_node_dict(self, hash=ht.dag_hash):
             )
 
         if self.external:
+            if self.extra_attributes:
+                extra_attributes = syaml.sorted_dict(self.extra_attributes)
+            else:
+                extra_attributes = None
+
             d["external"] = syaml.syaml_dict(
                 [
                     ("path", self.external_path),
                     ("module", self.external_modules),
-                    ("extra_attributes", self.extra_attributes),
+                    ("extra_attributes", extra_attributes),
                 ]
             )
 
@@ -2818,44 +2952,16 @@ def ensure_no_deprecated(root):
             raise SpecDeprecatedError(msg)
 
     def concretize(self, tests: Union[bool, Iterable[str]] = False) -> None:
-        """Concretize the current spec.
+        from spack.concretize import concretize_one
 
-        Args:
-            tests: if False disregard 'test' dependencies, if a list of names activate them for
-                the packages in the list, if True activate 'test' dependencies for all packages.
-        """
-        import spack.solver.asp
+        warnings.warn(
+            "`Spec.concretize` is deprecated and will be removed in version 1.0.0. Use "
+            "`spack.concretize.concretize_one` instead.",
+            category=spack.error.SpackAPIWarning,
+            stacklevel=2,
+        )
 
-        self.replace_hash()
-
-        for node in self.traverse():
-            if not node.name:
-                raise spack.error.SpecError(
-                    f"Spec {node} has no name; cannot concretize an anonymous spec"
-                )
-
-        if self._concrete:
-            return
-
-        allow_deprecated = spack.config.get("config:deprecated", False)
-        solver = spack.solver.asp.Solver()
-        result = solver.solve([self], tests=tests, allow_deprecated=allow_deprecated)
-
-        # take the best answer
-        opt, i, answer = min(result.answers)
-        name = self.name
-        # TODO: Consolidate this code with similar code in solve.py
-        if self.virtual:
-            providers = [spec.name for spec in answer.values() if spec.package.provides(name)]
-            name = providers[0]
-
-        node = spack.solver.asp.SpecBuilder.make_node(pkg=name)
-        assert (
-            node in answer
-        ), f"cannot find {name} in the list of specs {','.join([n.pkg for n in answer.keys()])}"
-
-        concretized = answer[node]
-        self._dup(concretized)
+        self._dup(concretize_one(self, tests))
 
     def _mark_root_concrete(self, value=True):
         """Mark just this spec (not dependencies) concrete."""
@@ -2944,20 +3050,17 @@ def _finalize_concretization(self):
         for spec in self.traverse():
             spec._cached_hash(ht.dag_hash)
 
-    def concretized(self, tests: Union[bool, Iterable[str]] = False) -> "spack.spec.Spec":
-        """This is a non-destructive version of concretize().
+    def concretized(self, tests: Union[bool, Iterable[str]] = False) -> "Spec":
+        from spack.concretize import concretize_one
 
-        First clones, then returns a concrete version of this package
-        without modifying this package.
+        warnings.warn(
+            "`Spec.concretized` is deprecated and will be removed in version 1.0.0. Use "
+            "`spack.concretize.concretize_one` instead.",
+            category=spack.error.SpackAPIWarning,
+            stacklevel=2,
+        )
 
-        Args:
-            tests (bool or list): if False disregard 'test' dependencies,
-                if a list of names activate them for the packages in the list,
-                if True activate 'test' dependencies for all packages.
-        """
-        clone = self.copy()
-        clone.concretize(tests=tests)
-        return clone
+        return concretize_one(self, tests)
 
     def index(self, deptype="all"):
         """Return a dictionary that points to all the dependencies in this
@@ -3493,25 +3596,16 @@ def patches(self):
 
         return self._patches
 
-    def _dup(self, other, deps: Union[bool, dt.DepTypes, dt.DepFlag] = True, cleardeps=True):
-        """Copy the spec other into self.  This is an overwriting
-        copy. It does not copy any dependents (parents), but by default
-        copies dependencies.
-
-        To duplicate an entire DAG, call _dup() on the root of the DAG.
+    def _dup(self, other: "Spec", deps: Union[bool, dt.DepTypes, dt.DepFlag] = True) -> bool:
+        """Copies "other" into self, by overwriting all attributes.
 
         Args:
-            other (Spec): spec to be copied onto ``self``
-            deps: if True copies all the dependencies. If
-                False copies None. If deptype/depflag, copy matching types.
-            cleardeps (bool): if True clears the dependencies of ``self``,
-                before possibly copying the dependencies of ``other`` onto
-                ``self``
+            other: spec to be copied onto ``self``
+            deps: if True copies all the dependencies. If False copies None.
+                If deptype, or depflag, copy matching types.
 
         Returns:
-            True if ``self`` changed because of the copy operation,
-            False otherwise.
-
+            True if ``self`` changed because of the copy operation, False otherwise.
         """
         # We don't count dependencies as changes here
         changed = True
@@ -3536,14 +3630,15 @@ def _dup(self, other, deps: Union[bool, dt.DepTypes, dt.DepFlag] = True, clearde
         self.versions = other.versions.copy()
         self.architecture = other.architecture.copy() if other.architecture else None
         self.compiler = other.compiler.copy() if other.compiler else None
-        if cleardeps:
-            self._dependents = _EdgeMap(store_by_child=False)
-            self._dependencies = _EdgeMap(store_by_child=True)
         self.compiler_flags = other.compiler_flags.copy()
         self.compiler_flags.spec = self
         self.variants = other.variants.copy()
         self._build_spec = other._build_spec
 
+        # Clear dependencies
+        self._dependents = _EdgeMap(store_by_child=False)
+        self._dependencies = _EdgeMap(store_by_child=True)
+
         # FIXME: we manage _patches_in_order_of_appearance specially here
         # to keep it from leaking out of spec.py, but we should figure
         # out how to handle it more elegantly in the Variant classes.
@@ -4048,15 +4143,7 @@ def __str__(self):
         if not self._dependencies:
             return self.format()
 
-        root_str = [self.format()]
-        sorted_dependencies = sorted(
-            self.traverse(root=False), key=lambda x: (x.name, x.abstract_hash)
-        )
-        sorted_dependencies = [
-            d.format("{edge_attributes} " + DEFAULT_FORMAT) for d in sorted_dependencies
-        ]
-        spec_str = " ^".join(root_str + sorted_dependencies)
-        return spec_str.strip()
+        return self.long_spec
 
     @property
     def colored_str(self):
@@ -4105,10 +4192,10 @@ def tree(
         depth: bool = False,
         hashes: bool = False,
         hashlen: Optional[int] = None,
-        cover: str = "nodes",
+        cover: spack.traverse.CoverType = "nodes",
         indent: int = 0,
         format: str = DEFAULT_FORMAT,
-        deptypes: Union[Tuple[str, ...], str] = "all",
+        deptypes: Union[dt.DepTypes, dt.DepFlag] = dt.ALL,
         show_types: bool = False,
         depth_first: bool = False,
         recurse_dependencies: bool = True,
@@ -4434,7 +4521,7 @@ def mask_build_deps(in_spec):
 
         return spec
 
-    def clear_caches(self, ignore=()):
+    def clear_caches(self, ignore: Tuple[str, ...] = ()) -> None:
         """
         Clears all cached hashes in a Spec, while preserving other properties.
         """

lib/spack/spack/test/abi_splicing.py

@@ -7,35 +7,14 @@
 
 import pytest
 
+import spack.concretize
 import spack.config
 import spack.deptypes as dt
-import spack.solver.asp
 from spack.installer import PackageInstaller
+from spack.solver.asp import SolverError
 from spack.spec import Spec
 
 
-class CacheManager:
-    def __init__(self, specs: List[str]) -> None:
-        self.req_specs = specs
-        self.concr_specs: List[Spec]
-        self.concr_specs = []
-
-    def __enter__(self):
-        self.concr_specs = [Spec(s).concretized() for s in self.req_specs]
-        for s in self.concr_specs:
-            PackageInstaller([s.package], fake=True, explicit=True).install()
-
-    def __exit__(self, exc_type, exc_val, exc_tb):
-        for s in self.concr_specs:
-            s.package.do_uninstall()
-
-
-# MacOS and Windows only work if you pass this function pointer rather than a
-# closure
-def _mock_has_runtime_dependencies(_x):
-    return True
-
-
 def _make_specs_non_buildable(specs: List[str]):
     output_config = {}
     for spec in specs:
@@ -44,203 +23,262 @@ def _make_specs_non_buildable(specs: List[str]):
 
 
 @pytest.fixture
-def splicing_setup(mutable_database, mock_packages, monkeypatch):
-    spack.config.set("concretizer:reuse", True)
-    monkeypatch.setattr(
-        spack.solver.asp, "_has_runtime_dependencies", _mock_has_runtime_dependencies
-    )
+def install_specs(
+    mutable_database,
+    mock_packages,
+    mutable_config,
+    do_not_check_runtimes_on_reuse,
+    install_mockery,
+):
+    """Returns a function that concretizes and installs a list of abstract specs"""
+    mutable_config.set("concretizer:reuse", True)
+
+    def _impl(*specs_str):
+        concrete_specs = [Spec(s).concretized() for s in specs_str]
+        PackageInstaller([s.package for s in concrete_specs], fake=True, explicit=True).install()
+        return concrete_specs
+
+    return _impl
 
 
 def _enable_splicing():
     spack.config.set("concretizer:splice", {"automatic": True})
 
 
-def _has_build_dependency(spec: Spec, name: str):
-    return any(s.name == name for s in spec.dependencies(None, dt.BUILD))
+@pytest.mark.parametrize("spec_str", ["splice-z", "splice-h@1"])
+def test_spec_reuse(spec_str, install_specs, mutable_config):
+    """Tests reuse of splice-z, without splicing, as a root and as a dependency of splice-h"""
+    splice_z = install_specs("splice-z@1.0.0+compat")[0]
+    mutable_config.set("packages", _make_specs_non_buildable(["splice-z"]))
+    concrete = spack.concretize.concretize_one(spec_str)
+    assert concrete["splice-z"].satisfies(splice_z)
 
 
-def test_simple_reuse(splicing_setup):
-    with CacheManager(["splice-z@1.0.0+compat"]):
-        spack.config.set("packages", _make_specs_non_buildable(["splice-z"]))
-        assert Spec("splice-z").concretized().satisfies(Spec("splice-z"))
-
-
-def test_simple_dep_reuse(splicing_setup):
-    with CacheManager(["splice-z@1.0.0+compat"]):
-        spack.config.set("packages", _make_specs_non_buildable(["splice-z"]))
-        assert Spec("splice-h@1").concretized().satisfies(Spec("splice-h@1"))
-
-
-def test_splice_installed_hash(splicing_setup):
-    cache = [
+@pytest.mark.regression("48578")
+def test_splice_installed_hash(install_specs, mutable_config):
+    """Tests splicing the dependency of an installed spec, for another installed spec"""
+    splice_t, splice_h = install_specs(
         "splice-t@1 ^splice-h@1.0.0+compat ^splice-z@1.0.0",
         "splice-h@1.0.2+compat ^splice-z@1.0.0",
-    ]
-    with CacheManager(cache):
-        packages_config = _make_specs_non_buildable(["splice-t", "splice-h"])
-        spack.config.set("packages", packages_config)
-        goal_spec = Spec("splice-t@1 ^splice-h@1.0.2+compat ^splice-z@1.0.0")
-        with pytest.raises(Exception):
-            goal_spec.concretized()
-        _enable_splicing()
-        assert goal_spec.concretized().satisfies(goal_spec)
+    )
+    packages_config = _make_specs_non_buildable(["splice-t", "splice-h"])
+    mutable_config.set("packages", packages_config)
+
+    goal_spec = "splice-t@1 ^splice-h@1.0.2+compat ^splice-z@1.0.0"
+    with pytest.raises(SolverError):
+        spack.concretize.concretize_one(goal_spec)
+    _enable_splicing()
+    concrete = spack.concretize.concretize_one(goal_spec)
+
+    # splice-t has a dependency that is changing, thus its hash should be different
+    assert concrete.dag_hash() != splice_t.dag_hash()
+    assert concrete.build_spec.satisfies(splice_t)
+    assert not concrete.satisfies(splice_t)
+
+    # splice-h is reused, so the hash should stay the same
+    assert concrete["splice-h"].satisfies(splice_h)
+    assert concrete["splice-h"].build_spec.satisfies(splice_h)
+    assert concrete["splice-h"].dag_hash() == splice_h.dag_hash()
 
 
-def test_splice_build_splice_node(splicing_setup):
-    with CacheManager(["splice-t@1 ^splice-h@1.0.0+compat ^splice-z@1.0.0+compat"]):
-        spack.config.set("packages", _make_specs_non_buildable(["splice-t"]))
-        goal_spec = Spec("splice-t@1 ^splice-h@1.0.2+compat ^splice-z@1.0.0+compat")
-        with pytest.raises(Exception):
-            goal_spec.concretized()
-        _enable_splicing()
-        assert goal_spec.concretized().satisfies(goal_spec)
+def test_splice_build_splice_node(install_specs, mutable_config):
+    """Tests splicing the dependency of an installed spec, for a spec that is yet to be built"""
+    splice_t = install_specs("splice-t@1 ^splice-h@1.0.0+compat ^splice-z@1.0.0+compat")[0]
+    mutable_config.set("packages", _make_specs_non_buildable(["splice-t"]))
+
+    goal_spec = "splice-t@1 ^splice-h@1.0.2+compat ^splice-z@1.0.0+compat"
+    with pytest.raises(SolverError):
+        spack.concretize.concretize_one(goal_spec)
+
+    _enable_splicing()
+    concrete = spack.concretize.concretize_one(goal_spec)
+
+    # splice-t has a dependency that is changing, thus its hash should be different
+    assert concrete.dag_hash() != splice_t.dag_hash()
+    assert concrete.build_spec.satisfies(splice_t)
+    assert not concrete.satisfies(splice_t)
+
+    # splice-h should be different
+    assert concrete["splice-h"].dag_hash() != splice_t["splice-h"].dag_hash()
+    assert concrete["splice-h"].build_spec.dag_hash() == concrete["splice-h"].dag_hash()
 
 
-def test_double_splice(splicing_setup):
-    cache = [
+def test_double_splice(install_specs, mutable_config):
+    """Tests splicing two dependencies of an installed spec, for other installed specs"""
+    splice_t, splice_h, splice_z = install_specs(
         "splice-t@1 ^splice-h@1.0.0+compat ^splice-z@1.0.0+compat",
         "splice-h@1.0.2+compat ^splice-z@1.0.1+compat",
         "splice-z@1.0.2+compat",
-    ]
-    with CacheManager(cache):
-        freeze_builds_config = _make_specs_non_buildable(["splice-t", "splice-h", "splice-z"])
-        spack.config.set("packages", freeze_builds_config)
-        goal_spec = Spec("splice-t@1 ^splice-h@1.0.2+compat ^splice-z@1.0.2+compat")
-        with pytest.raises(Exception):
-            goal_spec.concretized()
-        _enable_splicing()
-        assert goal_spec.concretized().satisfies(goal_spec)
+    )
+    mutable_config.set("packages", _make_specs_non_buildable(["splice-t", "splice-h", "splice-z"]))
+
+    goal_spec = "splice-t@1 ^splice-h@1.0.2+compat ^splice-z@1.0.2+compat"
+    with pytest.raises(SolverError):
+        spack.concretize.concretize_one(goal_spec)
+
+    _enable_splicing()
+    concrete = spack.concretize.concretize_one(goal_spec)
+
+    # splice-t and splice-h have a dependency that is changing, thus its hash should be different
+    assert concrete.dag_hash() != splice_t.dag_hash()
+    assert concrete.build_spec.satisfies(splice_t)
+    assert not concrete.satisfies(splice_t)
+
+    assert concrete["splice-h"].dag_hash() != splice_h.dag_hash()
+    assert concrete["splice-h"].build_spec.satisfies(splice_h)
+    assert not concrete["splice-h"].satisfies(splice_h)
+
+    # splice-z is reused, so the hash should stay the same
+    assert concrete["splice-z"].dag_hash() == splice_z.dag_hash()
 
 
-# The next two tests are mirrors of one another
-def test_virtual_multi_splices_in(splicing_setup):
-    cache = [
-        "depends-on-virtual-with-abi ^virtual-abi-1",
-        "depends-on-virtual-with-abi ^virtual-abi-2",
-    ]
-    goal_specs = [
-        "depends-on-virtual-with-abi ^virtual-abi-multi abi=one",
-        "depends-on-virtual-with-abi ^virtual-abi-multi abi=two",
-    ]
-    with CacheManager(cache):
-        spack.config.set("packages", _make_specs_non_buildable(["depends-on-virtual-with-abi"]))
-        for gs in goal_specs:
-            with pytest.raises(Exception):
-                Spec(gs).concretized()
-        _enable_splicing()
-        for gs in goal_specs:
-            assert Spec(gs).concretized().satisfies(gs)
+@pytest.mark.parametrize(
+    "original_spec,goal_spec",
+    [
+        # `virtual-abi-1` can be spliced for `virtual-abi-multi abi=one` and vice-versa
+        (
+            "depends-on-virtual-with-abi ^virtual-abi-1",
+            "depends-on-virtual-with-abi ^virtual-abi-multi abi=one",
+        ),
+        (
+            "depends-on-virtual-with-abi ^virtual-abi-multi abi=one",
+            "depends-on-virtual-with-abi ^virtual-abi-1",
+        ),
+        # `virtual-abi-2` can be spliced for `virtual-abi-multi abi=two` and vice-versa
+        (
+            "depends-on-virtual-with-abi ^virtual-abi-2",
+            "depends-on-virtual-with-abi ^virtual-abi-multi abi=two",
+        ),
+        (
+            "depends-on-virtual-with-abi ^virtual-abi-multi abi=two",
+            "depends-on-virtual-with-abi ^virtual-abi-2",
+        ),
+    ],
+)
+def test_virtual_multi_splices_in(original_spec, goal_spec, install_specs, mutable_config):
+    """Tests that we can splice a virtual dependency with a different, but compatible, provider."""
+    original = install_specs(original_spec)[0]
+    mutable_config.set("packages", _make_specs_non_buildable(["depends-on-virtual-with-abi"]))
+
+    with pytest.raises(SolverError):
+        spack.concretize.concretize_one(goal_spec)
+
+    _enable_splicing()
+    spliced = spack.concretize.concretize_one(goal_spec)
+
+    assert spliced.dag_hash() != original.dag_hash()
+    assert spliced.build_spec.dag_hash() == original.dag_hash()
+    assert spliced["virtual-with-abi"].name != spliced.build_spec["virtual-with-abi"].name
 
 
-def test_virtual_multi_can_be_spliced(splicing_setup):
-    cache = [
-        "depends-on-virtual-with-abi ^virtual-abi-multi abi=one",
-        "depends-on-virtual-with-abi ^virtual-abi-multi abi=two",
-    ]
-    goal_specs = [
-        "depends-on-virtual-with-abi ^virtual-abi-1",
-        "depends-on-virtual-with-abi ^virtual-abi-2",
-    ]
-    with CacheManager(cache):
-        spack.config.set("packages", _make_specs_non_buildable(["depends-on-virtual-with-abi"]))
-        with pytest.raises(Exception):
-            for gs in goal_specs:
-                Spec(gs).concretized()
-        _enable_splicing()
-        for gs in goal_specs:
-            assert Spec(gs).concretized().satisfies(gs)
-
-
-def test_manyvariant_star_matching_variant_splice(splicing_setup):
-    cache = [
+@pytest.mark.parametrize(
+    "original_spec,goal_spec",
+    [
         # can_splice("manyvariants@1.0.0", when="@1.0.1", match_variants="*")
-        "depends-on-manyvariants ^manyvariants@1.0.0+a+b c=v1 d=v2",
-        "depends-on-manyvariants ^manyvariants@1.0.0~a~b c=v3 d=v3",
-    ]
-    goal_specs = [
-        Spec("depends-on-manyvariants ^manyvariants@1.0.1+a+b c=v1 d=v2"),
-        Spec("depends-on-manyvariants ^manyvariants@1.0.1~a~b c=v3 d=v3"),
-    ]
-    with CacheManager(cache):
-        freeze_build_config = {"depends-on-manyvariants": {"buildable": False}}
-        spack.config.set("packages", freeze_build_config)
-        for goal in goal_specs:
-            with pytest.raises(Exception):
-                goal.concretized()
-        _enable_splicing()
-        for goal in goal_specs:
-            assert goal.concretized().satisfies(goal)
-
-
-def test_manyvariant_limited_matching(splicing_setup):
-    cache = [
+        (
+            "depends-on-manyvariants ^manyvariants@1.0.0+a+b c=v1 d=v2",
+            "depends-on-manyvariants ^manyvariants@1.0.1+a+b c=v1 d=v2",
+        ),
+        (
+            "depends-on-manyvariants ^manyvariants@1.0.0~a~b c=v3 d=v3",
+            "depends-on-manyvariants ^manyvariants@1.0.1~a~b c=v3 d=v3",
+        ),
         # can_splice("manyvariants@2.0.0+a~b", when="@2.0.1~a+b", match_variants=["c", "d"])
-        "depends-on-manyvariants@2.0 ^manyvariants@2.0.0+a~b c=v3 d=v2",
+        (
+            "depends-on-manyvariants@2.0 ^manyvariants@2.0.0+a~b c=v3 d=v2",
+            "depends-on-manyvariants@2.0 ^manyvariants@2.0.1~a+b c=v3 d=v2",
+        ),
         # can_splice("manyvariants@2.0.0 c=v1 d=v1", when="@2.0.1+a+b")
-        "depends-on-manyvariants@2.0 ^manyvariants@2.0.0~a~b c=v1 d=v1",
-    ]
-    goal_specs = [
-        Spec("depends-on-manyvariants@2.0 ^manyvariants@2.0.1~a+b c=v3 d=v2"),
-        Spec("depends-on-manyvariants@2.0 ^manyvariants@2.0.1+a+b c=v3 d=v3"),
-    ]
-    with CacheManager(cache):
-        freeze_build_config = {"depends-on-manyvariants": {"buildable": False}}
-        spack.config.set("packages", freeze_build_config)
-        for s in goal_specs:
-            with pytest.raises(Exception):
-                s.concretized()
-        _enable_splicing()
-        for s in goal_specs:
-            assert s.concretized().satisfies(s)
+        (
+            "depends-on-manyvariants@2.0 ^manyvariants@2.0.0~a~b c=v1 d=v1",
+            "depends-on-manyvariants@2.0 ^manyvariants@2.0.1+a+b c=v3 d=v3",
+        ),
+    ],
+)
+def test_manyvariant_matching_variant_splice(
+    original_spec, goal_spec, install_specs, mutable_config
+):
+    """Tests splicing with different kind of matching on variants"""
+    original = install_specs(original_spec)[0]
+    mutable_config.set("packages", {"depends-on-manyvariants": {"buildable": False}})
+
+    with pytest.raises(SolverError):
+        spack.concretize.concretize_one(goal_spec)
+
+    _enable_splicing()
+    spliced = spack.concretize.concretize_one(goal_spec)
+
+    assert spliced.dag_hash() != original.dag_hash()
+    assert spliced.build_spec.dag_hash() == original.dag_hash()
+
+    # The spliced 'manyvariants' is yet to be built
+    assert spliced["manyvariants"].dag_hash() != original["manyvariants"].dag_hash()
+    assert spliced["manyvariants"].build_spec.dag_hash() == spliced["manyvariants"].dag_hash()
 
 
-def test_external_splice_same_name(splicing_setup):
-    cache = [
+def test_external_splice_same_name(install_specs, mutable_config):
+    """Tests that externals can be spliced for non-external specs"""
+    original_splice_h, original_splice_t = install_specs(
         "splice-h@1.0.0 ^splice-z@1.0.0+compat",
         "splice-t@1.0 ^splice-h@1.0.1 ^splice-z@1.0.1+compat",
-    ]
-    packages_yaml = {
-        "splice-z": {"externals": [{"spec": "splice-z@1.0.2+compat", "prefix": "/usr"}]}
-    }
-    goal_specs = [
-        Spec("splice-h@1.0.0 ^splice-z@1.0.2"),
-        Spec("splice-t@1.0 ^splice-h@1.0.1 ^splice-z@1.0.2"),
-    ]
-    with CacheManager(cache):
-        spack.config.set("packages", packages_yaml)
-        _enable_splicing()
-        for s in goal_specs:
-            assert s.concretized().satisfies(s)
+    )
+    mutable_config.set("packages", _make_specs_non_buildable(["splice-t", "splice-h"]))
+    mutable_config.set(
+        "packages",
+        {
+            "splice-z": {
+                "externals": [{"spec": "splice-z@1.0.2+compat", "prefix": "/usr"}],
+                "buildable": False,
+            }
+        },
+    )
+
+    _enable_splicing()
+    concrete_splice_h = spack.concretize.concretize_one("splice-h@1.0.0 ^splice-z@1.0.2")
+    concrete_splice_t = spack.concretize.concretize_one(
+        "splice-t@1.0 ^splice-h@1.0.1 ^splice-z@1.0.2"
+    )
+
+    assert concrete_splice_h.dag_hash() != original_splice_h.dag_hash()
+    assert concrete_splice_h.build_spec.dag_hash() == original_splice_h.dag_hash()
+    assert concrete_splice_h["splice-z"].external
+
+    assert concrete_splice_t.dag_hash() != original_splice_t.dag_hash()
+    assert concrete_splice_t.build_spec.dag_hash() == original_splice_t.dag_hash()
+    assert concrete_splice_t["splice-z"].external
+
+    assert concrete_splice_t["splice-z"].dag_hash() == concrete_splice_h["splice-z"].dag_hash()
 
 
-def test_spliced_build_deps_only_in_build_spec(splicing_setup):
-    cache = ["splice-t@1.0 ^splice-h@1.0.1 ^splice-z@1.0.0"]
-    goal_spec = Spec("splice-t@1.0 ^splice-h@1.0.2 ^splice-z@1.0.0")
+def test_spliced_build_deps_only_in_build_spec(install_specs):
+    """Tests that build specs are not reported in the spliced spec"""
+    install_specs("splice-t@1.0 ^splice-h@1.0.1 ^splice-z@1.0.0")
 
-    with CacheManager(cache):
-        _enable_splicing()
-        concr_goal = goal_spec.concretized()
-        build_spec = concr_goal._build_spec
-        # Spec has been spliced
-        assert build_spec is not None
-        # Build spec has spliced build dependencies
-        assert _has_build_dependency(build_spec, "splice-h")
-        assert _has_build_dependency(build_spec, "splice-z")
-        # Spliced build dependencies are removed
-        assert len(concr_goal.dependencies(None, dt.BUILD)) == 0
+    _enable_splicing()
+    spliced = spack.concretize.concretize_one("splice-t@1.0 ^splice-h@1.0.2 ^splice-z@1.0.0")
+    build_spec = spliced.build_spec
+
+    # Spec has been spliced
+    assert build_spec.dag_hash() != spliced.dag_hash()
+    # Build spec has spliced build dependencies
+    assert build_spec.dependencies("splice-h", dt.BUILD)
+    assert build_spec.dependencies("splice-z", dt.BUILD)
+    # Spliced build dependencies are removed
+    assert len(spliced.dependencies(None, dt.BUILD)) == 0
 
 
-def test_spliced_transitive_dependency(splicing_setup):
-    cache = ["splice-depends-on-t@1.0 ^splice-h@1.0.1"]
-    goal_spec = Spec("splice-depends-on-t^splice-h@1.0.2")
+def test_spliced_transitive_dependency(install_specs, mutable_config):
+    """Tests that build specs are not reported, even for spliced transitive dependencies"""
+    install_specs("splice-depends-on-t@1.0 ^splice-h@1.0.1")
+    mutable_config.set("packages", _make_specs_non_buildable(["splice-depends-on-t"]))
 
-    with CacheManager(cache):
-        spack.config.set("packages", _make_specs_non_buildable(["splice-depends-on-t"]))
-        _enable_splicing()
-        concr_goal = goal_spec.concretized()
-        # Spec has been spliced
-        assert concr_goal._build_spec is not None
-        assert concr_goal["splice-t"]._build_spec is not None
-        assert concr_goal.satisfies(goal_spec)
-        # Spliced build dependencies are removed
-        assert len(concr_goal.dependencies(None, dt.BUILD)) == 0
+    _enable_splicing()
+    spliced = spack.concretize.concretize_one("splice-depends-on-t^splice-h@1.0.2")
+
+    # Spec has been spliced
+    assert spliced.build_spec.dag_hash() != spliced.dag_hash()
+    assert spliced["splice-t"].build_spec.dag_hash() != spliced["splice-t"].dag_hash()
+
+    # Spliced build dependencies are removed
+    assert len(spliced.dependencies(None, dt.BUILD)) == 0
+    assert len(spliced["splice-t"].dependencies(None, dt.BUILD)) == 0

lib/spack/spack/test/architecture.py

@@ -133,5 +133,5 @@ def test_concretize_target_ranges(root_target_range, dep_target_range, result, m
         f"pkg-a %gcc@10 foobar=bar target={root_target_range} ^pkg-b target={dep_target_range}"
     )
     with spack.concretize.disable_compiler_existence_check():
-        spec.concretize()
+        spec = spack.concretize.concretize_one(spec)
     assert spec.target == spec["pkg-b"].target == result

lib/spack/spack/test/bindist.py

@@ -28,6 +28,7 @@
 import spack.binary_distribution as bindist
 import spack.caches
 import spack.compilers
+import spack.concretize
 import spack.config
 import spack.fetch_strategy
 import spack.hooks.sbang as sbang
@@ -36,14 +37,13 @@
 import spack.oci.image
 import spack.paths
 import spack.spec
-import spack.stage
 import spack.store
 import spack.util.gpg
 import spack.util.spack_yaml as syaml
 import spack.util.url as url_util
 import spack.util.web as web_util
 from spack.binary_distribution import CannotListKeys, GenerateIndexError
-from spack.directory_layout import DirectoryLayout
+from spack.installer import PackageInstaller
 from spack.paths import test_path
 from spack.spec import Spec
 
@@ -136,35 +136,28 @@ def default_config(tmp_path, config_directory, monkeypatch, install_mockery):
 @pytest.fixture(scope="function")
 def install_dir_default_layout(tmpdir):
     """Hooks a fake install directory with a default layout"""
-    scheme = os.path.join(
-        "${architecture}", "${compiler.name}-${compiler.version}", "${name}-${version}-${hash}"
-    )
-    real_store, real_layout = spack.store.STORE, spack.store.STORE.layout
     opt_dir = tmpdir.join("opt")
-    spack.store.STORE = spack.store.Store(str(opt_dir))
-    spack.store.STORE.layout = DirectoryLayout(str(opt_dir), path_scheme=scheme)
+    original_store, spack.store.STORE = spack.store.STORE, spack.store.Store(str(opt_dir))
     try:
         yield spack.store
     finally:
-        spack.store.STORE = real_store
-        spack.store.STORE.layout = real_layout
+        spack.store.STORE = original_store
 
 
 @pytest.fixture(scope="function")
 def install_dir_non_default_layout(tmpdir):
     """Hooks a fake install directory with a non-default layout"""
-    scheme = os.path.join(
-        "${name}", "${version}", "${architecture}-${compiler.name}-${compiler.version}-${hash}"
-    )
-    real_store, real_layout = spack.store.STORE, spack.store.STORE.layout
     opt_dir = tmpdir.join("opt")
-    spack.store.STORE = spack.store.Store(str(opt_dir))
-    spack.store.STORE.layout = DirectoryLayout(str(opt_dir), path_scheme=scheme)
+    original_store, spack.store.STORE = spack.store.STORE, spack.store.Store(
+        str(opt_dir),
+        projections={
+            "all": "{name}/{version}/{architecture}-{compiler.name}-{compiler.version}-{hash}"
+        },
+    )
     try:
         yield spack.store
     finally:
-        spack.store.STORE = real_store
-        spack.store.STORE.layout = real_layout
+        spack.store.STORE = original_store
 
 
 @pytest.fixture(scope="function")
@@ -213,8 +206,9 @@ def test_default_rpaths_create_install_default_layout(temporary_mirror_dir):
     Test the creation and installation of buildcaches with default rpaths
     into the default directory layout scheme.
     """
-    gspec, cspec = Spec("garply").concretized(), Spec("corge").concretized()
-    sy_spec = Spec("symly").concretized()
+    gspec = spack.concretize.concretize_one("garply")
+    cspec = spack.concretize.concretize_one("corge")
+    sy_spec = spack.concretize.concretize_one("symly")
 
     # Install 'corge' without using a cache
     install_cmd("--no-cache", cspec.name)
@@ -261,9 +255,9 @@ def test_default_rpaths_install_nondefault_layout(temporary_mirror_dir):
     Test the creation and installation of buildcaches with default rpaths
     into the non-default directory layout scheme.
     """
-    cspec = Spec("corge").concretized()
+    cspec = spack.concretize.concretize_one("corge")
     # This guy tests for symlink relocation
-    sy_spec = Spec("symly").concretized()
+    sy_spec = spack.concretize.concretize_one("symly")
 
     # Install some packages with dependent packages
     # test install in non-default install path scheme
@@ -284,7 +278,8 @@ def test_relative_rpaths_install_default_layout(temporary_mirror_dir):
     Test the creation and installation of buildcaches with relative
     rpaths into the default directory layout scheme.
     """
-    gspec, cspec = Spec("garply").concretized(), Spec("corge").concretized()
+    gspec = spack.concretize.concretize_one("garply")
+    cspec = spack.concretize.concretize_one("corge")
 
     # Install buildcache created with relativized rpaths
     buildcache_cmd("install", "-uf", cspec.name)
@@ -313,7 +308,7 @@ def test_relative_rpaths_install_nondefault(temporary_mirror_dir):
     Test the installation of buildcaches with relativized rpaths
     into the non-default directory layout scheme.
     """
-    cspec = Spec("corge").concretized()
+    cspec = spack.concretize.concretize_one("corge")
 
     # Test install in non-default install path scheme and relative path
     buildcache_cmd("install", "-uf", cspec.name)
@@ -366,7 +361,8 @@ def test_built_spec_cache(temporary_mirror_dir):
     that cache from a buildcache index."""
     buildcache_cmd("list", "-a", "-l")
 
-    gspec, cspec = Spec("garply").concretized(), Spec("corge").concretized()
+    gspec = spack.concretize.concretize_one("garply")
+    cspec = spack.concretize.concretize_one("corge")
 
     for s in [gspec, cspec]:
         results = bindist.get_mirrors_for_spec(s)
@@ -389,7 +385,7 @@ def test_spec_needs_rebuild(monkeypatch, tmpdir):
     mirror_dir = tmpdir.join("mirror_dir")
     mirror_url = url_util.path_to_file_url(mirror_dir.strpath)
 
-    s = Spec("libdwarf").concretized()
+    s = spack.concretize.concretize_one("libdwarf")
 
     # Install a package
     install_cmd(s.name)
@@ -418,7 +414,7 @@ def test_generate_index_missing(monkeypatch, tmpdir, mutable_config):
     mirror_url = url_util.path_to_file_url(mirror_dir.strpath)
     spack.config.set("mirrors", {"test": mirror_url})
 
-    s = Spec("libdwarf").concretized()
+    s = spack.concretize.concretize_one("libdwarf")
 
     # Install a package
     install_cmd("--no-cache", s.name)
@@ -500,74 +496,40 @@ def mock_list_url(url, recursive=False):
     assert f"Encountered problem listing packages at {url}" in capfd.readouterr().err
 
 
-@pytest.mark.usefixtures("mock_fetch", "install_mockery")
-def test_update_sbang(tmpdir, temporary_mirror):
-    """Test the creation and installation of buildcaches with default rpaths
-    into the non-default directory layout scheme, triggering an update of the
-    sbang.
-    """
-    spec_str = "old-sbang"
-    # Concretize a package with some old-fashioned sbang lines.
-    old_spec = Spec(spec_str).concretized()
-    old_spec_hash_str = "/{0}".format(old_spec.dag_hash())
+def test_update_sbang(tmp_path, temporary_mirror, mock_fetch, install_mockery):
+    """Test relocation of the sbang shebang line in a package script"""
+    s = spack.concretize.concretize_one("old-sbang")
+    PackageInstaller([s.package]).install()
+    old_prefix, old_sbang_shebang = s.prefix, sbang.sbang_shebang_line()
+    old_contents = f"""\
+{old_sbang_shebang}
+#!/usr/bin/env python3
 
-    # Need a fake mirror with *function* scope.
-    mirror_dir = temporary_mirror
-
-    # Assume all commands will concretize old_spec the same way.
-    install_cmd("--no-cache", old_spec.name)
+{s.prefix.bin}
+"""
+    with open(os.path.join(s.prefix.bin, "script.sh"), encoding="utf-8") as f:
+        assert f.read() == old_contents
 
     # Create a buildcache with the installed spec.
-    buildcache_cmd("push", "-u", mirror_dir, old_spec_hash_str)
-
-    # Need to force an update of the buildcache index
-    buildcache_cmd("update-index", mirror_dir)
-
-    # Uninstall the original package.
-    uninstall_cmd("-y", old_spec_hash_str)
+    buildcache_cmd("push", "--update-index", "--unsigned", temporary_mirror, f"/{s.dag_hash()}")
 
     # Switch the store to the new install tree locations
-    newtree_dir = tmpdir.join("newtree")
-    with spack.store.use_store(str(newtree_dir)):
-        new_spec = Spec("old-sbang").concretized()
-        assert new_spec.dag_hash() == old_spec.dag_hash()
+    with spack.store.use_store(str(tmp_path)):
+        s._prefix = None  # clear the cached old prefix
+        new_prefix, new_sbang_shebang = s.prefix, sbang.sbang_shebang_line()
+        assert old_prefix != new_prefix
+        assert old_sbang_shebang != new_sbang_shebang
+        PackageInstaller([s.package], cache_only=True, unsigned=True).install()
 
-        # Install package from buildcache
-        buildcache_cmd("install", "-u", "-f", new_spec.name)
+        # Check that the sbang line refers to the new install tree
+        new_contents = f"""\
+{sbang.sbang_shebang_line()}
+#!/usr/bin/env python3
 
-        # Continue blowing away caches
-        bindist.clear_spec_cache()
-        spack.stage.purge()
-
-        # test that the sbang was updated by the move
-        sbang_style_1_expected = """{0}
-#!/usr/bin/env python
-
-{1}
-""".format(
-            sbang.sbang_shebang_line(), new_spec.prefix.bin
-        )
-        sbang_style_2_expected = """{0}
-#!/usr/bin/env python
-
-{1}
-""".format(
-            sbang.sbang_shebang_line(), new_spec.prefix.bin
-        )
-
-        installed_script_style_1_path = new_spec.prefix.bin.join("sbang-style-1.sh")
-        assert (
-            sbang_style_1_expected
-            == open(str(installed_script_style_1_path), encoding="utf-8").read()
-        )
-
-        installed_script_style_2_path = new_spec.prefix.bin.join("sbang-style-2.sh")
-        assert (
-            sbang_style_2_expected
-            == open(str(installed_script_style_2_path), encoding="utf-8").read()
-        )
-
-        uninstall_cmd("-y", "/%s" % new_spec.dag_hash())
+{s.prefix.bin}
+"""
+        with open(os.path.join(s.prefix.bin, "script.sh"), encoding="utf-8") as f:
+            assert f.read() == new_contents
 
 
 @pytest.mark.skipif(

lib/spack/spack/test/build_distribution.py

@@ -8,15 +8,15 @@
 import pytest
 
 import spack.binary_distribution as bd
+import spack.concretize
 import spack.mirrors.mirror
-import spack.spec
 from spack.installer import PackageInstaller
 
 pytestmark = pytest.mark.not_on_windows("does not run on windows")
 
 
 def test_build_tarball_overwrite(install_mockery, mock_fetch, monkeypatch, tmp_path):
-    spec = spack.spec.Spec("trivial-install-test-package").concretized()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
     PackageInstaller([spec.package], fake=True).install()
 
     specs = [spec]

lib/spack/spack/test/build_environment.py

@@ -16,6 +16,7 @@
 import spack.build_environment
 import spack.compiler
 import spack.compilers
+import spack.concretize
 import spack.config
 import spack.deptypes as dt
 import spack.package_base
@@ -163,8 +164,7 @@ def test_static_to_shared_library(build_environment):
 @pytest.mark.regression("8345")
 @pytest.mark.usefixtures("config", "mock_packages")
 def test_cc_not_changed_by_modules(monkeypatch, working_env):
-    s = spack.spec.Spec("cmake")
-    s.concretize()
+    s = spack.concretize.concretize_one("cmake")
     pkg = s.package
 
     def _set_wrong_cc(x):
@@ -184,7 +184,7 @@ def test_setup_dependent_package_inherited_modules(
     working_env, mock_packages, install_mockery, mock_fetch
 ):
     # This will raise on regression
-    s = spack.spec.Spec("cmake-client-inheritor").concretized()
+    s = spack.concretize.concretize_one("cmake-client-inheritor")
     PackageInstaller([s.package]).install()
 
 
@@ -277,7 +277,7 @@ def platform_pathsep(pathlist):
         return convert_to_platform_path(pathlist)
 
     # Monkeypatch a pkg.compiler.environment with the required modifications
-    pkg = spack.spec.Spec("cmake").concretized().package
+    pkg = spack.concretize.concretize_one("cmake").package
     monkeypatch.setattr(pkg.compiler, "environment", modifications)
     # Trigger the modifications
     spack.build_environment.setup_package(pkg, False)
@@ -301,7 +301,7 @@ def custom_env(pkg, env):
         env.prepend_path("PATH", test_path)
         env.append_flags("ENV_CUSTOM_CC_FLAGS", "--custom-env-flag1")
 
-    pkg = spack.spec.Spec("cmake").concretized().package
+    pkg = spack.concretize.concretize_one("cmake").package
     monkeypatch.setattr(pkg.compiler, "setup_custom_environment", custom_env)
     spack.build_environment.setup_package(pkg, False)
 
@@ -322,7 +322,7 @@ def test_external_config_env(mock_packages, mutable_config, working_env):
     }
     spack.config.set("packages:cmake", cmake_config)
 
-    cmake_client = spack.spec.Spec("cmake-client").concretized()
+    cmake_client = spack.concretize.concretize_one("cmake-client")
     spack.build_environment.setup_package(cmake_client.package, False)
 
     assert os.environ["TEST_ENV_VAR_SET"] == "yes it's set"
@@ -330,8 +330,7 @@ def test_external_config_env(mock_packages, mutable_config, working_env):
 
 @pytest.mark.regression("9107")
 def test_spack_paths_before_module_paths(config, mock_packages, monkeypatch, working_env):
-    s = spack.spec.Spec("cmake")
-    s.concretize()
+    s = spack.concretize.concretize_one("cmake")
     pkg = s.package
 
     module_path = os.path.join("path", "to", "module")
@@ -352,8 +351,7 @@ def _set_wrong_cc(x):
 
 
 def test_package_inheritance_module_setup(config, mock_packages, working_env):
-    s = spack.spec.Spec("multimodule-inheritance")
-    s.concretize()
+    s = spack.concretize.concretize_one("multimodule-inheritance")
     pkg = s.package
 
     spack.build_environment.setup_package(pkg, False)
@@ -387,8 +385,7 @@ def test_wrapper_variables(
         not in cuda_include_dirs
     )
 
-    root = spack.spec.Spec("dt-diamond")
-    root.concretize()
+    root = spack.concretize.concretize_one("dt-diamond")
 
     for s in root.traverse():
         s.prefix = "/{0}-prefix/".format(s.name)
@@ -453,7 +450,7 @@ def test_external_prefixes_last(mutable_config, mock_packages, working_env, monk
 """
     )
     spack.config.set("packages", cfg_data)
-    top = spack.spec.Spec("dt-diamond").concretized()
+    top = spack.concretize.concretize_one("dt-diamond")
 
     def _trust_me_its_a_dir(path):
         return True
@@ -500,8 +497,7 @@ def test_parallel_false_is_not_propagating(default_mock_concretization):
 )
 def test_setting_dtags_based_on_config(config_setting, expected_flag, config, mock_packages):
     # Pick a random package to be able to set compiler's variables
-    s = spack.spec.Spec("cmake")
-    s.concretize()
+    s = spack.concretize.concretize_one("cmake")
     pkg = s.package
 
     env = EnvironmentModifications()
@@ -533,7 +529,7 @@ def setup_dependent_package(module, dependent_spec):
         assert dependent_module.ninja is not None
         dependent_spec.package.test_attr = True
 
-    externaltool = spack.spec.Spec("externaltest").concretized()
+    externaltool = spack.concretize.concretize_one("externaltest")
     monkeypatch.setattr(
         externaltool["externaltool"].package, "setup_dependent_package", setup_dependent_package
     )
@@ -728,7 +724,7 @@ def test_build_system_globals_only_set_on_root_during_build(default_mock_concret
     But obviously it can lead to very hard to find bugs... We should get rid of those globals and
     define them instead as a property on the package instance.
     """
-    root = spack.spec.Spec("mpileaks").concretized()
+    root = spack.concretize.concretize_one("mpileaks")
     build_variables = ("std_cmake_args", "std_meson_args", "std_pip_args")
 
     # See todo above, we clear out any properties that may have been set by the previous test.

lib/spack/spack/test/build_systems.py

@@ -15,12 +15,13 @@
 import spack.build_systems.autotools
 import spack.build_systems.cmake
 import spack.builder
+import spack.concretize
 import spack.environment
 import spack.error
 import spack.paths
 import spack.platforms
 import spack.platforms.test
-from spack.build_environment import ChildError, setup_package
+from spack.build_environment import ChildError, MakeExecutable, setup_package
 from spack.installer import PackageInstaller
 from spack.spec import Spec
 from spack.util.executable import which
@@ -29,10 +30,12 @@
 
 
 @pytest.fixture()
-def concretize_and_setup(default_mock_concretization):
+def concretize_and_setup(default_mock_concretization, monkeypatch):
     def _func(spec_str):
         s = default_mock_concretization(spec_str)
         setup_package(s.package, False)
+        monkeypatch.setattr(s.package.module, "make", MakeExecutable("make", jobs=1))
+        monkeypatch.setattr(s.package.module, "ninja", MakeExecutable("ninja", jobs=1))
         return s
 
     return _func
@@ -144,7 +147,7 @@ def test_none_is_allowed(self, default_mock_concretization):
 
     def test_libtool_archive_files_are_deleted_by_default(self, mutable_database):
         # Install a package that creates a mock libtool archive
-        s = Spec("libtool-deletion").concretized()
+        s = spack.concretize.concretize_one("libtool-deletion")
         PackageInstaller([s.package], explicit=True).install()
 
         # Assert the libtool archive is not there and we have
@@ -159,7 +162,7 @@ def test_libtool_archive_files_might_be_installed_on_demand(
     ):
         # Install a package that creates a mock libtool archive,
         # patch its package to preserve the installation
-        s = Spec("libtool-deletion").concretized()
+        s = spack.concretize.concretize_one("libtool-deletion")
         monkeypatch.setattr(
             type(spack.builder.create(s.package)), "install_libtool_archives", True
         )
@@ -173,7 +176,9 @@ def test_autotools_gnuconfig_replacement(self, mutable_database):
         Tests whether only broken config.sub and config.guess are replaced with
         files from working alternatives from the gnuconfig package.
         """
-        s = Spec("autotools-config-replacement +patch_config_files +gnuconfig").concretized()
+        s = spack.concretize.concretize_one(
+            Spec("autotools-config-replacement +patch_config_files +gnuconfig")
+        )
         PackageInstaller([s.package]).install()
 
         with open(os.path.join(s.prefix.broken, "config.sub"), encoding="utf-8") as f:
@@ -192,7 +197,9 @@ def test_autotools_gnuconfig_replacement_disabled(self, mutable_database):
         """
         Tests whether disabling patch_config_files
         """
-        s = Spec("autotools-config-replacement ~patch_config_files +gnuconfig").concretized()
+        s = spack.concretize.concretize_one(
+            Spec("autotools-config-replacement ~patch_config_files +gnuconfig")
+        )
         PackageInstaller([s.package]).install()
 
         with open(os.path.join(s.prefix.broken, "config.sub"), encoding="utf-8") as f:
@@ -217,8 +224,9 @@ def test_autotools_gnuconfig_replacement_no_gnuconfig(self, mutable_database, mo
         enabled, but gnuconfig is not listed as a direct build dependency.
         """
         monkeypatch.setattr(spack.platforms.test.Test, "default", "x86_64")
-        s = Spec("autotools-config-replacement +patch_config_files ~gnuconfig")
-        s.concretize()
+        s = spack.concretize.concretize_one(
+            Spec("autotools-config-replacement +patch_config_files ~gnuconfig")
+        )
 
         msg = "Cannot patch config files: missing dependencies: gnuconfig"
         with pytest.raises(ChildError, match=msg):
@@ -298,7 +306,7 @@ def test_define(self, default_mock_concretization):
         assert define("SINGLE", "red") == "-DSINGLE:STRING=red"
 
     def test_define_from_variant(self):
-        s = Spec("cmake-client multi=up,right ~truthy single=red").concretized()
+        s = spack.concretize.concretize_one("cmake-client multi=up,right ~truthy single=red")
 
         arg = s.package.define_from_variant("MULTI")
         assert arg == "-DMULTI:STRING=right;up"

lib/spack/spack/test/builder.py

@@ -8,9 +8,9 @@
 from llnl.util.filesystem import touch
 
 import spack.builder
+import spack.concretize
 import spack.paths
 import spack.repo
-import spack.spec
 
 
 @pytest.fixture()
@@ -78,7 +78,7 @@ def builder_test_repository():
 @pytest.mark.disable_clean_stage_check
 def test_callbacks_and_installation_procedure(spec_str, expected_values, working_env):
     """Test the correct execution of callbacks and installation procedures for packages."""
-    s = spack.spec.Spec(spec_str).concretized()
+    s = spack.concretize.concretize_one(spec_str)
     builder = spack.builder.create(s.package)
     for phase_fn in builder:
         phase_fn.execute()
@@ -101,7 +101,7 @@ def test_callbacks_and_installation_procedure(spec_str, expected_values, working
     ],
 )
 def test_old_style_compatibility_with_super(spec_str, method_name, expected):
-    s = spack.spec.Spec(spec_str).concretized()
+    s = spack.concretize.concretize_one(spec_str)
     builder = spack.builder.create(s.package)
     value = getattr(builder, method_name)()
     assert value == expected
@@ -112,7 +112,7 @@ def test_old_style_compatibility_with_super(spec_str, method_name, expected):
 @pytest.mark.usefixtures("builder_test_repository", "config", "working_env")
 @pytest.mark.disable_clean_stage_check
 def test_build_time_tests_are_executed_from_default_builder():
-    s = spack.spec.Spec("old-style-autotools").concretized()
+    s = spack.concretize.concretize_one("old-style-autotools")
     builder = spack.builder.create(s.package)
     builder.pkg.run_tests = True
     for phase_fn in builder:
@@ -126,7 +126,7 @@ def test_build_time_tests_are_executed_from_default_builder():
 @pytest.mark.usefixtures("builder_test_repository", "config", "working_env")
 def test_monkey_patching_wrapped_pkg():
     """Confirm 'run_tests' is accessible through wrappers."""
-    s = spack.spec.Spec("old-style-autotools").concretized()
+    s = spack.concretize.concretize_one("old-style-autotools")
     builder = spack.builder.create(s.package)
     assert s.package.run_tests is False
     assert builder.pkg.run_tests is False
@@ -141,7 +141,7 @@ def test_monkey_patching_wrapped_pkg():
 @pytest.mark.usefixtures("builder_test_repository", "config", "working_env")
 def test_monkey_patching_test_log_file():
     """Confirm 'test_log_file' is accessible through wrappers."""
-    s = spack.spec.Spec("old-style-autotools").concretized()
+    s = spack.concretize.concretize_one("old-style-autotools")
     builder = spack.builder.create(s.package)
 
     s.package.tester.test_log_file = "/some/file"
@@ -154,7 +154,7 @@ def test_monkey_patching_test_log_file():
 @pytest.mark.not_on_windows("Does not run on windows")
 def test_install_time_test_callback(tmpdir, config, mock_packages, mock_stage):
     """Confirm able to run stand-alone test as a post-install callback."""
-    s = spack.spec.Spec("py-test-callback").concretized()
+    s = spack.concretize.concretize_one("py-test-callback")
     builder = spack.builder.create(s.package)
     builder.pkg.run_tests = True
     s.package.tester.test_log_file = tmpdir.join("install_test.log")
@@ -174,7 +174,7 @@ def test_mixins_with_builders(working_env):
     """Tests that run_after and run_before callbacks are accumulated correctly,
     when mixins are used with builders.
     """
-    s = spack.spec.Spec("builder-and-mixins").concretized()
+    s = spack.concretize.concretize_one("builder-and-mixins")
     builder = spack.builder.create(s.package)
 
     # Check that callbacks added by the mixin are in the list

lib/spack/spack/test/buildrequest.py

@@ -4,6 +4,7 @@
 
 import pytest
 
+import spack.concretize
 import spack.deptypes as dt
 import spack.installer as inst
 import spack.repo
@@ -21,8 +22,7 @@ def test_build_request_errors(install_mockery):
 
 
 def test_build_request_basics(install_mockery):
-    spec = spack.spec.Spec("dependent-install")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("dependent-install")
     assert spec.concrete
 
     # Ensure key properties match expectations
@@ -39,8 +39,7 @@ def test_build_request_basics(install_mockery):
 def test_build_request_strings(install_mockery):
     """Tests of BuildRequest repr and str for coverage purposes."""
     # Using a package with one dependency
-    spec = spack.spec.Spec("dependent-install")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("dependent-install")
     assert spec.concrete
 
     # Ensure key properties match expectations
@@ -72,7 +71,7 @@ def test_build_request_deptypes(
     package_deptypes,
     dependencies_deptypes,
 ):
-    s = spack.spec.Spec("dependent-install").concretized()
+    s = spack.concretize.concretize_one("dependent-install")
 
     build_request = inst.BuildRequest(
         s.package,

lib/spack/spack/test/buildtask.py

@@ -4,6 +4,7 @@
 
 import pytest
 
+import spack.concretize
 import spack.error
 import spack.installer as inst
 import spack.repo
@@ -24,7 +25,7 @@ def test_build_task_errors(install_mockery):
         inst.BuildTask(pkg_cls(spec), None)
 
     # Using a concretized package now means the request argument is checked.
-    spec.concretize()
+    spec = spack.concretize.concretize_one(spec)
     assert spec.concrete
 
     with pytest.raises(TypeError, match="is not a valid build request"):
@@ -47,8 +48,7 @@ def test_build_task_errors(install_mockery):
 
 
 def test_build_task_basics(install_mockery):
-    spec = spack.spec.Spec("dependent-install")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("dependent-install")
     assert spec.concrete
 
     # Ensure key properties match expectations
@@ -69,8 +69,7 @@ def test_build_task_basics(install_mockery):
 def test_build_task_strings(install_mockery):
     """Tests of build_task repr and str for coverage purposes."""
     # Using a package with one dependency
-    spec = spack.spec.Spec("dependent-install")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("dependent-install")
     assert spec.concrete
 
     # Ensure key properties match expectations

lib/spack/spack/test/ci.py

@@ -9,13 +9,12 @@
 import llnl.util.filesystem as fs
 
 import spack.ci as ci
+import spack.concretize
 import spack.environment as ev
 import spack.error
 import spack.paths as spack_paths
 import spack.repo as repo
-import spack.spec
 import spack.util.git
-from spack.spec import Spec
 
 pytestmark = [pytest.mark.usefixtures("mock_packages")]
 
@@ -54,7 +53,7 @@ def test_pipeline_dag(config, tmpdir):
     builder.add_package("pkg-a", dependencies=[("pkg-b", None, None), ("pkg-c", None, None)])
 
     with repo.use_repositories(builder.root):
-        spec_a = Spec("pkg-a").concretized()
+        spec_a = spack.concretize.concretize_one("pkg-a")
 
         key_a = ci.common.PipelineDag.key(spec_a)
         key_b = ci.common.PipelineDag.key(spec_a["pkg-b"])
@@ -449,7 +448,7 @@ def test_ci_run_standalone_tests_not_installed_junit(
     log_file = tmp_path / "junit.xml"
     args = {
         "log_file": str(log_file),
-        "job_spec": spack.spec.Spec("printing-package").concretized(),
+        "job_spec": spack.concretize.concretize_one("printing-package"),
         "repro_dir": str(repro_dir),
         "fail_fast": True,
     }
@@ -468,7 +467,7 @@ def test_ci_run_standalone_tests_not_installed_cdash(
     log_file = tmp_path / "junit.xml"
     args = {
         "log_file": str(log_file),
-        "job_spec": spack.spec.Spec("printing-package").concretized(),
+        "job_spec": spack.concretize.concretize_one("printing-package"),
         "repro_dir": str(repro_dir),
     }
 
@@ -501,7 +500,7 @@ def test_ci_run_standalone_tests_not_installed_cdash(
 def test_ci_skipped_report(tmpdir, mock_packages, config):
     """Test explicit skipping of report as well as CI's 'package' arg."""
     pkg = "trivial-smoke-test"
-    spec = spack.spec.Spec(pkg).concretized()
+    spec = spack.concretize.concretize_one(pkg)
     ci_cdash = {
         "url": "file://fake",
         "build-group": "fake-group",

lib/spack/spack/test/cmd/bootstrap.py

@@ -10,6 +10,7 @@
 
 import spack.bootstrap
 import spack.bootstrap.core
+import spack.concretize
 import spack.config
 import spack.environment as ev
 import spack.main
@@ -183,7 +184,7 @@ def test_bootstrap_mirror_metadata(mutable_config, linux_os, monkeypatch, tmpdir
     """
     old_create = spack.mirrors.utils.create
     monkeypatch.setattr(spack.mirrors.utils, "create", lambda p, s: old_create(p, []))
-    monkeypatch.setattr(spack.spec.Spec, "concretized", lambda p: p)
+    monkeypatch.setattr(spack.concretize, "concretize_one", lambda p: spack.spec.Spec(p))
 
     # Create the mirror in a temporary folder
     compilers = [

lib/spack/spack/test/cmd/buildcache.py

@@ -12,6 +12,7 @@
 
 import spack.binary_distribution
 import spack.cmd.buildcache
+import spack.concretize
 import spack.environment as ev
 import spack.error
 import spack.main
@@ -19,7 +20,6 @@
 import spack.spec
 import spack.util.url
 from spack.installer import PackageInstaller
-from spack.spec import Spec
 
 buildcache = spack.main.SpackCommand("buildcache")
 install = spack.main.SpackCommand("install")
@@ -81,7 +81,7 @@ def tests_buildcache_create(install_mockery, mock_fetch, monkeypatch, tmpdir):
 
     buildcache("push", "--unsigned", str(tmpdir), pkg)
 
-    spec = Spec(pkg).concretized()
+    spec = spack.concretize.concretize_one(pkg)
     tarball_path = spack.binary_distribution.tarball_path_name(spec, ".spack")
     tarball = spack.binary_distribution.tarball_name(spec, ".spec.json")
     assert os.path.exists(os.path.join(str(tmpdir), "build_cache", tarball_path))
@@ -101,7 +101,7 @@ def tests_buildcache_create_env(
 
         buildcache("push", "--unsigned", str(tmpdir))
 
-    spec = Spec(pkg).concretized()
+    spec = spack.concretize.concretize_one(pkg)
     tarball_path = spack.binary_distribution.tarball_path_name(spec, ".spack")
     tarball = spack.binary_distribution.tarball_name(spec, ".spec.json")
     assert os.path.exists(os.path.join(str(tmpdir), "build_cache", tarball_path))
@@ -145,7 +145,7 @@ def test_update_key_index(
 
     gpg("create", "Test Signing Key", "nobody@nowhere.com")
 
-    s = Spec("libdwarf").concretized()
+    s = spack.concretize.concretize_one("libdwarf")
 
     # Install a package
     install(s.name)
@@ -175,7 +175,7 @@ def test_buildcache_autopush(tmp_path, install_mockery, mock_fetch):
     mirror("add", "--unsigned", "mirror", mirror_dir.as_uri())
     mirror("add", "--autopush", "--unsigned", "mirror-autopush", mirror_autopush_dir.as_uri())
 
-    s = Spec("libdwarf").concretized()
+    s = spack.concretize.concretize_one("libdwarf")
 
     # Install and generate build cache index
     PackageInstaller([s.package], explicit=True).install()
@@ -219,7 +219,7 @@ def verify_mirror_contents():
             assert False
 
     # Install a package and put it in the buildcache
-    s = Spec(out_env_pkg).concretized()
+    s = spack.concretize.concretize_one(out_env_pkg)
     install(s.name)
     buildcache("push", "-u", "-f", src_mirror_url, s.name)
 
@@ -329,7 +329,7 @@ def test_buildcache_create_install(
 
     buildcache("push", "--unsigned", str(tmpdir), pkg)
 
-    spec = Spec(pkg).concretized()
+    spec = spack.concretize.concretize_one(pkg)
     tarball_path = spack.binary_distribution.tarball_path_name(spec, ".spack")
     tarball = spack.binary_distribution.tarball_name(spec, ".spec.json")
     assert os.path.exists(os.path.join(str(tmpdir), "build_cache", tarball_path))
@@ -450,7 +450,7 @@ def test_push_and_install_with_mirror_marked_unsigned_does_not_require_extra_fla
 
 
 def test_skip_no_redistribute(mock_packages, config):
-    specs = list(Spec("no-redistribute-dependent").concretized().traverse())
+    specs = list(spack.concretize.concretize_one("no-redistribute-dependent").traverse())
     filtered = spack.cmd.buildcache._skip_no_redistribute_for_public(specs)
     assert not any(s.name == "no-redistribute" for s in filtered)
     assert any(s.name == "no-redistribute-dependent" for s in filtered)
@@ -490,7 +490,7 @@ def test_push_without_build_deps(tmp_path, temporary_store, mock_packages, mutab
 
     mirror("add", "--unsigned", "my-mirror", str(tmp_path))
 
-    s = spack.spec.Spec("dtrun3").concretized()
+    s = spack.concretize.concretize_one("dtrun3")
     PackageInstaller([s.package], explicit=True, fake=True).install()
     s["dtbuild3"].package.do_uninstall()
 

lib/spack/spack/test/cmd/checksum.py

@@ -7,10 +7,10 @@
 import pytest
 
 import spack.cmd.checksum
+import spack.concretize
 import spack.error
 import spack.package_base
 import spack.repo
-import spack.spec
 import spack.stage
 import spack.util.web
 from spack.main import SpackCommand
@@ -308,7 +308,7 @@ def test_checksum_url(mock_packages, config):
 
 
 def test_checksum_verification_fails(default_mock_concretization, capsys, can_fetch_versions):
-    spec = spack.spec.Spec("zlib").concretized()
+    spec = spack.concretize.concretize_one("zlib")
     pkg = spec.package
     versions = list(pkg.versions.keys())
     version_hashes = {versions[0]: "abadhash", Version("0.1"): "123456789"}

lib/spack/spack/test/cmd/ci.py

@@ -18,6 +18,7 @@
 import spack.ci as ci
 import spack.cmd
 import spack.cmd.ci
+import spack.concretize
 import spack.environment as ev
 import spack.hash_types as ht
 import spack.main
@@ -1056,7 +1057,7 @@ def test_ci_rebuild_index(
     with working_dir(tmp_path):
         env_cmd("create", "test", "./spack.yaml")
         with ev.read("test"):
-            concrete_spec = Spec("callpath").concretized()
+            concrete_spec = spack.concretize.concretize_one("callpath")
             with open(tmp_path / "spec.json", "w", encoding="utf-8") as f:
                 f.write(concrete_spec.to_json(hash=ht.dag_hash))
 
@@ -1177,12 +1178,10 @@ def test_ci_generate_read_broken_specs_url(
     ci_base_environment,
 ):
     """Verify that `broken-specs-url` works as intended"""
-    spec_a = Spec("pkg-a")
-    spec_a.concretize()
+    spec_a = spack.concretize.concretize_one("pkg-a")
     a_dag_hash = spec_a.dag_hash()
 
-    spec_flattendeps = Spec("flatten-deps")
-    spec_flattendeps.concretize()
+    spec_flattendeps = spack.concretize.concretize_one("flatten-deps")
     flattendeps_dag_hash = spec_flattendeps.dag_hash()
 
     broken_specs_url = tmp_path.as_uri()
@@ -1533,8 +1532,7 @@ def dynamic_mapping_setup(tmpdir):
 """
         )
 
-    spec_a = Spec("pkg-a")
-    spec_a.concretize()
+    spec_a = spack.concretize.concretize_one("pkg-a")
 
     return gitlab_generator.get_job_name(spec_a)
 

lib/spack/spack/test/cmd/clean.py

@@ -10,10 +10,8 @@
 
 import spack.caches
 import spack.cmd.clean
-import spack.environment as ev
 import spack.main
 import spack.package_base
-import spack.spec
 import spack.stage
 import spack.store
 
@@ -69,20 +67,6 @@ def test_function_calls(command_line, effects, mock_calls_for_clean):
         assert mock_calls_for_clean[name] == (1 if name in effects else 0)
 
 
-def test_env_aware_clean(mock_stage, install_mockery, mutable_mock_env_path, monkeypatch):
-    e = ev.create("test", with_view=False)
-    e.add("mpileaks")
-    e.concretize()
-
-    def fail(*args, **kwargs):
-        raise Exception("This should not have been called")
-
-    monkeypatch.setattr(spack.spec.Spec, "concretize", fail)
-
-    with e:
-        clean("mpileaks")
-
-
 def test_remove_python_cache(tmpdir, monkeypatch):
     cache_files = ["file1.pyo", "file2.pyc"]
     source_file = "file1.py"

lib/spack/spack/test/cmd/config.py

@@ -8,12 +8,12 @@
 
 import llnl.util.filesystem as fs
 
+import spack.concretize
 import spack.config
 import spack.database
 import spack.environment as ev
 import spack.main
 import spack.schema.config
-import spack.spec
 import spack.store
 import spack.util.spack_yaml as syaml
 
@@ -593,8 +593,7 @@ def test_config_prefer_upstream(
     prepared_db = spack.database.Database(mock_db_root, layout=gen_mock_layout("/a/"))
 
     for spec in ["hdf5 +mpi", "hdf5 ~mpi", "boost+debug~icu+graph", "dependency-install", "patch"]:
-        dep = spack.spec.Spec(spec)
-        dep.concretize()
+        dep = spack.concretize.concretize_one(spec)
         prepared_db.add(dep)
 
     downstream_db_root = str(tmpdir_factory.mktemp("mock_downstream_db_root"))

lib/spack/spack/test/cmd/deprecate.py

@@ -4,6 +4,7 @@
 
 import pytest
 
+import spack.concretize
 import spack.spec
 import spack.store
 from spack.enums import InstallRecordStatus
@@ -66,8 +67,8 @@ def test_deprecate_deps(mock_packages, mock_archive, mock_fetch, install_mockery
     install("libdwarf@20130729 ^libelf@0.8.13")
     install("libdwarf@20130207 ^libelf@0.8.10")
 
-    new_spec = spack.spec.Spec("libdwarf@20130729^libelf@0.8.13").concretized()
-    old_spec = spack.spec.Spec("libdwarf@20130207^libelf@0.8.10").concretized()
+    new_spec = spack.concretize.concretize_one("libdwarf@20130729^libelf@0.8.13")
+    old_spec = spack.concretize.concretize_one("libdwarf@20130207^libelf@0.8.10")
 
     all_installed = spack.store.STORE.db.query()
 
@@ -107,12 +108,12 @@ def test_deprecate_already_deprecated(mock_packages, mock_archive, mock_fetch, i
     install("libelf@0.8.12")
     install("libelf@0.8.10")
 
-    deprecated_spec = spack.spec.Spec("libelf@0.8.10").concretized()
+    deprecated_spec = spack.concretize.concretize_one("libelf@0.8.10")
 
     deprecate("-y", "libelf@0.8.10", "libelf@0.8.12")
 
     deprecator = spack.store.STORE.db.deprecator(deprecated_spec)
-    assert deprecator == spack.spec.Spec("libelf@0.8.12").concretized()
+    assert deprecator == spack.concretize.concretize_one("libelf@0.8.12")
 
     deprecate("-y", "libelf@0.8.10", "libelf@0.8.13")
 
@@ -122,7 +123,7 @@ def test_deprecate_already_deprecated(mock_packages, mock_archive, mock_fetch, i
     assert len(all_available) == 3
 
     deprecator = spack.store.STORE.db.deprecator(deprecated_spec)
-    assert deprecator == spack.spec.Spec("libelf@0.8.13").concretized()
+    assert deprecator == spack.concretize.concretize_one("libelf@0.8.13")
 
 
 def test_deprecate_deprecator(mock_packages, mock_archive, mock_fetch, install_mockery):
@@ -132,9 +133,9 @@ def test_deprecate_deprecator(mock_packages, mock_archive, mock_fetch, install_m
     install("libelf@0.8.12")
     install("libelf@0.8.10")
 
-    first_deprecated_spec = spack.spec.Spec("libelf@0.8.10").concretized()
-    second_deprecated_spec = spack.spec.Spec("libelf@0.8.12").concretized()
-    final_deprecator = spack.spec.Spec("libelf@0.8.13").concretized()
+    first_deprecated_spec = spack.concretize.concretize_one("libelf@0.8.10")
+    second_deprecated_spec = spack.concretize.concretize_one("libelf@0.8.12")
+    final_deprecator = spack.concretize.concretize_one("libelf@0.8.13")
 
     deprecate("-y", "libelf@0.8.10", "libelf@0.8.12")
 
@@ -164,7 +165,7 @@ def test_concretize_deprecated(mock_packages, mock_archive, mock_fetch, install_
 
     spec = spack.spec.Spec("libelf@0.8.10")
     with pytest.raises(spack.spec.SpecDeprecatedError):
-        spec.concretize()
+        spack.concretize.concretize_one(spec)
 
 
 @pytest.mark.usefixtures("mock_packages", "mock_archive", "mock_fetch", "install_mockery")

lib/spack/spack/test/cmd/dev_build.py

@@ -8,6 +8,7 @@
 
 import llnl.util.filesystem as fs
 
+import spack.concretize
 import spack.environment as ev
 import spack.error
 import spack.repo
@@ -23,7 +24,9 @@
 
 
 def test_dev_build_basics(tmpdir, install_mockery):
-    spec = spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={tmpdir}").concretized()
+    spec = spack.concretize.concretize_one(
+        spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={tmpdir}")
+    )
 
     assert "dev_path" in spec.variants
 
@@ -41,7 +44,9 @@ def test_dev_build_basics(tmpdir, install_mockery):
 
 
 def test_dev_build_before(tmpdir, install_mockery):
-    spec = spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={tmpdir}").concretized()
+    spec = spack.concretize.concretize_one(
+        spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={tmpdir}")
+    )
 
     with tmpdir.as_cwd():
         with open(spec.package.filename, "w", encoding="utf-8") as f:
@@ -57,7 +62,9 @@ def test_dev_build_before(tmpdir, install_mockery):
 
 
 def test_dev_build_until(tmpdir, install_mockery):
-    spec = spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={tmpdir}").concretized()
+    spec = spack.concretize.concretize_one(
+        spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={tmpdir}")
+    )
 
     with tmpdir.as_cwd():
         with open(spec.package.filename, "w", encoding="utf-8") as f:
@@ -75,7 +82,9 @@ def test_dev_build_until(tmpdir, install_mockery):
 
 def test_dev_build_until_last_phase(tmpdir, install_mockery):
     # Test that we ignore the last_phase argument if it is already last
-    spec = spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={tmpdir}").concretized()
+    spec = spack.concretize.concretize_one(
+        spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={tmpdir}")
+    )
 
     with tmpdir.as_cwd():
         with open(spec.package.filename, "w", encoding="utf-8") as f:
@@ -93,7 +102,9 @@ def test_dev_build_until_last_phase(tmpdir, install_mockery):
 
 
 def test_dev_build_before_until(tmpdir, install_mockery):
-    spec = spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={tmpdir}").concretized()
+    spec = spack.concretize.concretize_one(
+        spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={tmpdir}")
+    )
 
     with tmpdir.as_cwd():
         with open(spec.package.filename, "w", encoding="utf-8") as f:
@@ -129,8 +140,9 @@ def test_dev_build_drop_in(tmpdir, mock_packages, monkeypatch, install_mockery,
 
 
 def test_dev_build_fails_already_installed(tmpdir, install_mockery):
-    spec = spack.spec.Spec("dev-build-test-install@0.0.0 dev_path=%s" % tmpdir)
-    spec.concretize()
+    spec = spack.concretize.concretize_one(
+        spack.spec.Spec("dev-build-test-install@0.0.0 dev_path=%s" % tmpdir)
+    )
 
     with tmpdir.as_cwd():
         with open(spec.package.filename, "w", encoding="utf-8") as f:
@@ -172,8 +184,9 @@ def test_dev_build_env(tmpdir, install_mockery, mutable_mock_env_path):
     """Test Spack does dev builds for packages in develop section of env."""
     # setup dev-build-test-install package for dev build
     build_dir = tmpdir.mkdir("build")
-    spec = spack.spec.Spec("dev-build-test-install@0.0.0 dev_path=%s" % build_dir)
-    spec.concretize()
+    spec = spack.concretize.concretize_one(
+        spack.spec.Spec("dev-build-test-install@0.0.0 dev_path=%s" % build_dir)
+    )
 
     with build_dir.as_cwd():
         with open(spec.package.filename, "w", encoding="utf-8") as f:
@@ -208,8 +221,9 @@ def test_dev_build_env_with_vars(tmpdir, install_mockery, mutable_mock_env_path,
     """Test Spack does dev builds for packages in develop section of env (path with variables)."""
     # setup dev-build-test-install package for dev build
     build_dir = tmpdir.mkdir("build")
-    spec = spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={build_dir}")
-    spec.concretize()
+    spec = spack.concretize.concretize_one(
+        spack.spec.Spec(f"dev-build-test-install@0.0.0 dev_path={build_dir}")
+    )
 
     # store the build path in an environment variable that will be used in the environment
     monkeypatch.setenv("CUSTOM_BUILD_PATH", build_dir)
@@ -246,8 +260,9 @@ def test_dev_build_env_version_mismatch(tmpdir, install_mockery, mutable_mock_en
     """Test Spack constraints concretization by develop specs."""
     # setup dev-build-test-install package for dev build
     build_dir = tmpdir.mkdir("build")
-    spec = spack.spec.Spec("dev-build-test-install@0.0.0 dev_path=%s" % tmpdir)
-    spec.concretize()
+    spec = spack.concretize.concretize_one(
+        spack.spec.Spec("dev-build-test-install@0.0.0 dev_path=%s" % tmpdir)
+    )
 
     with build_dir.as_cwd():
         with open(spec.package.filename, "w", encoding="utf-8") as f:
@@ -327,8 +342,8 @@ def test_dev_build_multiple(tmpdir, install_mockery, mutable_mock_env_path, mock
         with ev.read("test"):
             # Do concretization inside environment for dev info
             # These specs are the source of truth to compare against the installs
-            leaf_spec.concretize()
-            root_spec.concretize()
+            leaf_spec = spack.concretize.concretize_one(leaf_spec)
+            root_spec = spack.concretize.concretize_one(root_spec)
 
             # Do install
             install()
@@ -374,8 +389,8 @@ def test_dev_build_env_dependency(tmpdir, install_mockery, mock_fetch, mutable_m
             # concretize in the environment to get the dev build info
             # equivalent to setting dev_build and dev_path variants
             # on all specs above
-            spec.concretize()
-            dep_spec.concretize()
+            spec = spack.concretize.concretize_one(spec)
+            dep_spec = spack.concretize.concretize_one(dep_spec)
             install()
 
     # Ensure that both specs installed properly
@@ -399,8 +414,9 @@ def test_dev_build_rebuild_on_source_changes(
     """
     # setup dev-build-test-install package for dev build
     build_dir = tmpdir.mkdir("build")
-    spec = spack.spec.Spec("dev-build-test-install@0.0.0 dev_path=%s" % build_dir)
-    spec.concretize()
+    spec = spack.concretize.concretize_one(
+        spack.spec.Spec("dev-build-test-install@0.0.0 dev_path=%s" % build_dir)
+    )
 
     def reset_string():
         with build_dir.as_cwd():

lib/spack/spack/test/cmd/develop.py

@@ -8,6 +8,7 @@
 
 import llnl.util.filesystem as fs
 
+import spack.concretize
 import spack.config
 import spack.environment as ev
 import spack.package_base
@@ -138,7 +139,8 @@ def check_path(stage, dest):
             self.check_develop(e, spack.spec.Spec("mpich@=1.0"), path)
 
             # Check modifications actually worked
-            assert spack.spec.Spec("mpich@1.0").concretized().satisfies("dev_path=%s" % abspath)
+            result = spack.concretize.concretize_one("mpich@1.0")
+            assert result.satisfies("dev_path=%s" % abspath)
 
     def test_develop_canonicalize_path_no_args(self, monkeypatch):
         env("create", "test")
@@ -165,7 +167,8 @@ def check_path(stage, dest):
             self.check_develop(e, spack.spec.Spec("mpich@=1.0"), path)
 
             # Check modifications actually worked
-            assert spack.spec.Spec("mpich@1.0").concretized().satisfies("dev_path=%s" % abspath)
+            result = spack.concretize.concretize_one("mpich@1.0")
+            assert result.satisfies("dev_path=%s" % abspath)
 
 
 def _git_commit_list(git_repo_dir):
@@ -190,7 +193,7 @@ def test_develop_full_git_repo(
         spack.package_base.PackageBase, "git", "file://%s" % repo_path, raising=False
     )
 
-    spec = spack.spec.Spec("git-test-commit@1.2").concretized()
+    spec = spack.concretize.concretize_one("git-test-commit@1.2")
     try:
         spec.package.do_stage()
         commits = _git_commit_list(spec.package.stage[0].source_path)

lib/spack/spack/test/cmd/diff.py

@@ -5,9 +5,9 @@
 import pytest
 
 import spack.cmd.diff
+import spack.concretize
 import spack.main
 import spack.repo
-import spack.spec
 import spack.util.spack_json as sjson
 from spack.test.conftest import create_test_repo
 
@@ -133,8 +133,8 @@ def test_repo(_create_test_repo, monkeypatch, mock_stage):
 
 
 def test_diff_ignore(test_repo):
-    specA = spack.spec.Spec("p1+usev1").concretized()
-    specB = spack.spec.Spec("p1~usev1").concretized()
+    specA = spack.concretize.concretize_one("p1+usev1")
+    specB = spack.concretize.concretize_one("p1~usev1")
 
     c1 = spack.cmd.diff.compare_specs(specA, specB, to_string=False)
 
@@ -154,8 +154,8 @@ def find(function_list, name, args):
 
     # Check ignoring changes on multiple packages
 
-    specA = spack.spec.Spec("p1+usev1 ^p3+p3var").concretized()
-    specA = spack.spec.Spec("p1~usev1 ^p3~p3var").concretized()
+    specA = spack.concretize.concretize_one("p1+usev1 ^p3+p3var")
+    specA = spack.concretize.concretize_one("p1~usev1 ^p3~p3var")
 
     c3 = spack.cmd.diff.compare_specs(specA, specB, to_string=False)
     assert find(c3["a_not_b"], "variant_value", ["p3", "p3var"])
@@ -168,8 +168,8 @@ def find(function_list, name, args):
 def test_diff_cmd(install_mockery, mock_fetch, mock_archive, mock_packages):
     """Test that we can install two packages and diff them"""
 
-    specA = spack.spec.Spec("mpileaks").concretized()
-    specB = spack.spec.Spec("mpileaks+debug").concretized()
+    specA = spack.concretize.concretize_one("mpileaks")
+    specB = spack.concretize.concretize_one("mpileaks+debug")
 
     # Specs should be the same as themselves
     c = spack.cmd.diff.compare_specs(specA, specA, to_string=True)

lib/spack/spack/test/cmd/env.py

@@ -19,6 +19,7 @@
 from llnl.util.symlink import readlink
 
 import spack.cmd.env
+import spack.concretize
 import spack.config
 import spack.environment as ev
 import spack.environment.depfile as depfile
@@ -957,7 +958,7 @@ def test_lockfile_spliced_specs(environment_from_manifest, install_mockery):
     """Test that an environment can round-trip a spliced spec."""
     # Create a local install for zmpi to splice in
     # Default concretization is not using zmpi
-    zmpi = spack.spec.Spec("zmpi").concretized()
+    zmpi = spack.concretize.concretize_one("zmpi")
     PackageInstaller([zmpi.package], fake=True).install()
 
     e1 = environment_from_manifest(
@@ -1320,39 +1321,43 @@ def test_config_change_existing(mutable_mock_env_path, tmp_path, mock_packages,
     with e:
         # List of requirements, flip a variant
         config("change", "packages:mpich:require:~debug")
-        test_spec = spack.spec.Spec("mpich").concretized()
+        test_spec = spack.concretize.concretize_one("mpich")
         assert test_spec.satisfies("@3.0.2~debug")
 
         # List of requirements, change the version (in a different scope)
         config("change", "packages:mpich:require:@3.0.3")
-        test_spec = spack.spec.Spec("mpich").concretized()
+        test_spec = spack.concretize.concretize_one("mpich")
         assert test_spec.satisfies("@3.0.3")
 
         # "require:" as a single string, also try specifying
         # a spec string that requires enclosing in quotes as
         # part of the config path
         config("change", 'packages:libelf:require:"@0.8.12:"')
-        spack.spec.Spec("libelf@0.8.12").concretized()
+        spack.concretize.concretize_one("libelf@0.8.12")
         # No need for assert, if there wasn't a failure, we
         # changed the requirement successfully.
 
         # Use change to add a requirement for a package that
         # has no requirements defined
         config("change", "packages:fftw:require:+mpi")
-        test_spec = spack.spec.Spec("fftw").concretized()
+        test_spec = spack.concretize.concretize_one("fftw")
         assert test_spec.satisfies("+mpi")
         config("change", "packages:fftw:require:~mpi")
-        test_spec = spack.spec.Spec("fftw").concretized()
+        test_spec = spack.concretize.concretize_one("fftw")
         assert test_spec.satisfies("~mpi")
         config("change", "packages:fftw:require:@1.0")
-        test_spec = spack.spec.Spec("fftw").concretized()
+        test_spec = spack.concretize.concretize_one("fftw")
         assert test_spec.satisfies("@1.0~mpi")
 
         # Use "--match-spec" to change one spec in a "one_of"
         # list
         config("change", "packages:bowtie:require:@1.2.2", "--match-spec", "@1.2.0")
-        spack.spec.Spec("bowtie@1.3.0").concretize()
-        spack.spec.Spec("bowtie@1.2.2").concretized()
+        # confirm that we can concretize to either value
+        spack.concretize.concretize_one("bowtie@1.3.0")
+        spack.concretize.concretize_one("bowtie@1.2.2")
+        # confirm that we cannot concretize to the old value
+        with pytest.raises(spack.solver.asp.UnsatisfiableSpecError):
+            spack.concretize.concretize_one("bowtie@1.2.0")
 
 
 def test_config_change_new(mutable_mock_env_path, tmp_path, mock_packages, mutable_config):
@@ -1367,8 +1372,8 @@ def test_config_change_new(mutable_mock_env_path, tmp_path, mock_packages, mutab
     with ev.Environment(tmp_path):
         config("change", "packages:mpich:require:~debug")
         with pytest.raises(spack.solver.asp.UnsatisfiableSpecError):
-            spack.spec.Spec("mpich+debug").concretized()
-        spack.spec.Spec("mpich~debug").concretized()
+            spack.concretize.concretize_one("mpich+debug")
+        spack.concretize.concretize_one("mpich~debug")
 
     # Now check that we raise an error if we need to add a require: constraint
     # when preexisting config manually specified it as a singular spec
@@ -1382,7 +1387,7 @@ def test_config_change_new(mutable_mock_env_path, tmp_path, mock_packages, mutab
 """
     )
     with ev.Environment(tmp_path):
-        assert spack.spec.Spec("mpich").concretized().satisfies("@3.0.3")
+        assert spack.concretize.concretize_one("mpich").satisfies("@3.0.3")
         with pytest.raises(spack.error.ConfigError, match="not a list"):
             config("change", "packages:mpich:require:~debug")
 
@@ -1690,7 +1695,7 @@ def test_stage(mock_stage, mock_fetch, install_mockery):
     root = str(mock_stage)
 
     def check_stage(spec):
-        spec = Spec(spec).concretized()
+        spec = spack.concretize.concretize_one(spec)
         for dep in spec.traverse():
             stage_name = f"{stage_prefix}{dep.name}-{dep.version}-{dep.dag_hash()}"
             assert os.path.isdir(os.path.join(root, stage_name))
@@ -1791,7 +1796,7 @@ def test_indirect_build_dep(tmp_path):
 
     with spack.repo.use_repositories(builder.root):
         x_spec = Spec("x")
-        x_concretized = x_spec.concretized()
+        x_concretized = spack.concretize.concretize_one(x_spec)
 
         _env_create("test", with_view=False)
         e = ev.read("test")
@@ -1824,10 +1829,10 @@ def test_store_different_build_deps(tmp_path):
 
     with spack.repo.use_repositories(builder.root):
         y_spec = Spec("y ^z@3")
-        y_concretized = y_spec.concretized()
+        y_concretized = spack.concretize.concretize_one(y_spec)
 
         x_spec = Spec("x ^z@2")
-        x_concretized = x_spec.concretized()
+        x_concretized = spack.concretize.concretize_one(x_spec)
 
         # Even though x chose a different 'z', the y it chooses should be identical
         # *aside* from the dependency on 'z'.  The dag_hash() will show the difference
@@ -2120,15 +2125,7 @@ def configure_reuse(reuse_mode, combined_env) -> Optional[ev.Environment]:
         "from_environment_raise",
     ],
 )
-def test_env_include_concrete_reuse(monkeypatch, reuse_mode):
-
-    # The mock packages do not use the gcc-runtime
-    def mock_has_runtime_dependencies(*args, **kwargs):
-        return True
-
-    monkeypatch.setattr(
-        spack.solver.asp, "_has_runtime_dependencies", mock_has_runtime_dependencies
-    )
+def test_env_include_concrete_reuse(do_not_check_runtimes_on_reuse, reuse_mode):
     # The default mpi version is 3.x provided by mpich in the mock repo.
     # This test verifies that concretizing with an included concrete
     # environment with "concretizer:reuse:true" the included

lib/spack/spack/test/cmd/extensions.py

@@ -5,16 +5,18 @@
 
 import pytest
 
+import spack.concretize
 from spack.installer import PackageInstaller
 from spack.main import SpackCommand, SpackCommandError
-from spack.spec import Spec
 
 extensions = SpackCommand("extensions")
 
 
 @pytest.fixture
 def python_database(mock_packages, mutable_database):
-    specs = [Spec(s).concretized() for s in ["python", "py-extension1", "py-extension2"]]
+    specs = [
+        spack.concretize.concretize_one(s) for s in ["python", "py-extension1", "py-extension2"]
+    ]
     PackageInstaller([s.package for s in specs], explicit=True, fake=True).install()
     yield
 
@@ -22,7 +24,7 @@ def python_database(mock_packages, mutable_database):
 @pytest.mark.not_on_windows("All Fetchers Failed")
 @pytest.mark.db
 def test_extensions(mock_packages, python_database, capsys):
-    ext2 = Spec("py-extension2").concretized()
+    ext2 = spack.concretize.concretize_one("py-extension2")
 
     def check_output(ni):
         with capsys.disabled():

lib/spack/spack/test/cmd/find.py

@@ -12,13 +12,13 @@
 
 import spack.cmd as cmd
 import spack.cmd.find
+import spack.concretize
 import spack.environment as ev
 import spack.repo
 import spack.store
 import spack.user_environment as uenv
 from spack.enums import InstallRecordStatus
 from spack.main import SpackCommand
-from spack.spec import Spec
 from spack.test.conftest import create_test_repo
 from spack.test.utilities import SpackCommandArgs
 from spack.util.pattern import Bunch
@@ -201,7 +201,8 @@ def test_find_json_deps(database):
 @pytest.mark.db
 def test_display_json(database, capsys):
     specs = [
-        Spec(s).concretized() for s in ["mpileaks ^zmpi", "mpileaks ^mpich", "mpileaks ^mpich2"]
+        spack.concretize.concretize_one(s)
+        for s in ["mpileaks ^zmpi", "mpileaks ^mpich", "mpileaks ^mpich2"]
     ]
 
     cmd.display_specs_as_json(specs)
@@ -216,7 +217,8 @@ def test_display_json(database, capsys):
 @pytest.mark.db
 def test_display_json_deps(database, capsys):
     specs = [
-        Spec(s).concretized() for s in ["mpileaks ^zmpi", "mpileaks ^mpich", "mpileaks ^mpich2"]
+        spack.concretize.concretize_one(s)
+        for s in ["mpileaks ^zmpi", "mpileaks ^mpich", "mpileaks ^mpich2"]
     ]
 
     cmd.display_specs_as_json(specs, deps=True)
@@ -275,7 +277,7 @@ def test_find_format_deps(database, config):
 def test_find_format_deps_paths(database, config):
     output = find("-dp", "--format", "{name}-{version}", "mpileaks", "^zmpi")
 
-    spec = Spec("mpileaks ^zmpi").concretized()
+    spec = spack.concretize.concretize_one("mpileaks ^zmpi")
     prefixes = [s.prefix for s in spec.traverse()]
 
     assert (
@@ -300,7 +302,8 @@ def test_find_very_long(database, config):
     output = find("-L", "--no-groups", "mpileaks")
 
     specs = [
-        Spec(s).concretized() for s in ["mpileaks ^zmpi", "mpileaks ^mpich", "mpileaks ^mpich2"]
+        spack.concretize.concretize_one(s)
+        for s in ["mpileaks ^zmpi", "mpileaks ^mpich", "mpileaks ^mpich2"]
     ]
 
     assert set(output.strip().split("\n")) == set(

lib/spack/spack/test/cmd/gc.py

@@ -5,6 +5,7 @@
 
 import pytest
 
+import spack.concretize
 import spack.deptypes as dt
 import spack.environment as ev
 import spack.main
@@ -25,8 +26,7 @@ def test_gc_without_build_dependency(mutable_database):
 
 @pytest.mark.db
 def test_gc_with_build_dependency(mutable_database):
-    s = spack.spec.Spec("simple-inheritance")
-    s.concretize()
+    s = spack.concretize.concretize_one("simple-inheritance")
     PackageInstaller([s.package], explicit=True, fake=True).install()
 
     assert "There are no unused specs." in gc("-yb")
@@ -36,8 +36,8 @@ def test_gc_with_build_dependency(mutable_database):
 
 @pytest.mark.db
 def test_gc_with_constraints(mutable_database):
-    s_cmake1 = spack.spec.Spec("simple-inheritance ^cmake@3.4.3").concretized()
-    s_cmake2 = spack.spec.Spec("simple-inheritance ^cmake@3.23.1").concretized()
+    s_cmake1 = spack.concretize.concretize_one("simple-inheritance ^cmake@3.4.3")
+    s_cmake2 = spack.concretize.concretize_one("simple-inheritance ^cmake@3.23.1")
     PackageInstaller([s_cmake1.package], explicit=True, fake=True).install()
     PackageInstaller([s_cmake2.package], explicit=True, fake=True).install()
 
@@ -52,8 +52,7 @@ def test_gc_with_constraints(mutable_database):
 
 @pytest.mark.db
 def test_gc_with_environment(mutable_database, mutable_mock_env_path):
-    s = spack.spec.Spec("simple-inheritance")
-    s.concretize()
+    s = spack.concretize.concretize_one("simple-inheritance")
     PackageInstaller([s.package], explicit=True, fake=True).install()
 
     e = ev.create("test_gc")
@@ -68,8 +67,7 @@ def test_gc_with_environment(mutable_database, mutable_mock_env_path):
 
 @pytest.mark.db
 def test_gc_with_build_dependency_in_environment(mutable_database, mutable_mock_env_path):
-    s = spack.spec.Spec("simple-inheritance")
-    s.concretize()
+    s = spack.concretize.concretize_one("simple-inheritance")
     PackageInstaller([s.package], explicit=True, fake=True).install()
 
     e = ev.create("test_gc")
@@ -120,8 +118,7 @@ def test_gc_except_any_environments(mutable_database, mutable_mock_env_path):
 
 @pytest.mark.db
 def test_gc_except_specific_environments(mutable_database, mutable_mock_env_path):
-    s = spack.spec.Spec("simple-inheritance")
-    s.concretize()
+    s = spack.concretize.concretize_one("simple-inheritance")
     PackageInstaller([s.package], explicit=True, fake=True).install()
 
     assert mutable_database.query_local("zmpi")
@@ -147,8 +144,7 @@ def test_gc_except_nonexisting_dir_env(mutable_database, mutable_mock_env_path,
 
 @pytest.mark.db
 def test_gc_except_specific_dir_env(mutable_database, mutable_mock_env_path, tmpdir):
-    s = spack.spec.Spec("simple-inheritance")
-    s.concretize()
+    s = spack.concretize.concretize_one("simple-inheritance")
     PackageInstaller([s.package], explicit=True, fake=True).install()
 
     assert mutable_database.query_local("zmpi")

lib/spack/spack/test/cmd/install.py

@@ -19,6 +19,7 @@
 import spack.build_environment
 import spack.cmd.common.arguments
 import spack.cmd.install
+import spack.concretize
 import spack.config
 import spack.environment as ev
 import spack.error
@@ -134,7 +135,7 @@ def test_package_output(tmpdir, capsys, install_mockery, mock_fetch):
     # we can't use output capture here because it interferes with Spack's
     # logging. TODO: see whether we can get multiple log_outputs to work
     # when nested AND in pytest
-    spec = Spec("printing-package").concretized()
+    spec = spack.concretize.concretize_one("printing-package")
     pkg = spec.package
     PackageInstaller([pkg], explicit=True, verbose=True).install()
 
@@ -174,7 +175,7 @@ def test_install_output_on_python_error(mock_packages, mock_archive, mock_fetch,
 def test_install_with_source(mock_packages, mock_archive, mock_fetch, install_mockery):
     """Verify that source has been copied into place."""
     install("--source", "--keep-stage", "trivial-install-test-package")
-    spec = Spec("trivial-install-test-package").concretized()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
     src = os.path.join(spec.prefix.share, "trivial-install-test-package", "src")
     assert filecmp.cmp(
         os.path.join(mock_archive.path, "configure"), os.path.join(src, "configure")
@@ -182,8 +183,7 @@ def test_install_with_source(mock_packages, mock_archive, mock_fetch, install_mo
 
 
 def test_install_env_variables(mock_packages, mock_archive, mock_fetch, install_mockery):
-    spec = Spec("libdwarf")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("libdwarf")
     install("libdwarf")
     assert os.path.isfile(spec.package.install_env_path)
 
@@ -204,8 +204,7 @@ def test_show_log_on_error(mock_packages, mock_archive, mock_fetch, install_mock
 
 def test_install_overwrite(mock_packages, mock_archive, mock_fetch, install_mockery):
     # Try to install a spec and then to reinstall it.
-    spec = Spec("libdwarf")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("libdwarf")
 
     install("libdwarf")
 
@@ -238,8 +237,7 @@ def test_install_overwrite(mock_packages, mock_archive, mock_fetch, install_mock
 
 def test_install_overwrite_not_installed(mock_packages, mock_archive, mock_fetch, install_mockery):
     # Try to install a spec and then to reinstall it.
-    spec = Spec("libdwarf")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("libdwarf")
 
     assert not os.path.exists(spec.prefix)
 
@@ -260,7 +258,7 @@ def test_install_commit(mock_git_version_info, install_mockery, mock_packages, m
     monkeypatch.setattr(spack.package_base.PackageBase, "git", file_url, raising=False)
 
     # Use the earliest commit in the respository
-    spec = Spec(f"git-test-commit@{commits[-1]}").concretized()
+    spec = spack.concretize.concretize_one(f"git-test-commit@{commits[-1]}")
     PackageInstaller([spec.package], explicit=True).install()
 
     # Ensure first commit file contents were written
@@ -273,13 +271,11 @@ def test_install_commit(mock_git_version_info, install_mockery, mock_packages, m
 
 def test_install_overwrite_multiple(mock_packages, mock_archive, mock_fetch, install_mockery):
     # Try to install a spec and then to reinstall it.
-    libdwarf = Spec("libdwarf")
-    libdwarf.concretize()
+    libdwarf = spack.concretize.concretize_one("libdwarf")
 
     install("libdwarf")
 
-    cmake = Spec("cmake")
-    cmake.concretize()
+    cmake = spack.concretize.concretize_one("cmake")
 
     install("cmake")
 
@@ -355,7 +351,7 @@ def test_install_invalid_spec():
 )
 def test_install_from_file(spec, concretize, error_code, tmpdir):
     if concretize:
-        spec.concretize()
+        spec = spack.concretize.concretize_one(spec)
 
     specfile = tmpdir.join("spec.yaml")
 
@@ -485,8 +481,7 @@ def test_install_mix_cli_and_files(clispecs, filespecs, tmpdir):
     for spec in filespecs:
         filepath = tmpdir.join(spec + ".yaml")
         args = ["-f", str(filepath)] + args
-        s = Spec(spec)
-        s.concretize()
+        s = spack.concretize.concretize_one(spec)
         with filepath.open("w") as f:
             s.to_yaml(f)
 
@@ -495,8 +490,7 @@ def test_install_mix_cli_and_files(clispecs, filespecs, tmpdir):
 
 
 def test_extra_files_are_archived(mock_packages, mock_archive, mock_fetch, install_mockery):
-    s = Spec("archive-files")
-    s.concretize()
+    s = spack.concretize.concretize_one("archive-files")
 
     install("archive-files")
 
@@ -615,8 +609,7 @@ def test_cdash_install_from_spec_json(
     with capfd.disabled(), tmpdir.as_cwd():
         spec_json_path = str(tmpdir.join("spec.json"))
 
-        pkg_spec = Spec("pkg-a")
-        pkg_spec.concretize()
+        pkg_spec = spack.concretize.concretize_one("pkg-a")
 
         with open(spec_json_path, "w", encoding="utf-8") as fd:
             fd.write(pkg_spec.to_json(hash=ht.dag_hash))
@@ -692,8 +685,8 @@ def test_cache_only_fails(tmpdir, mock_fetch, install_mockery, capfd):
 
 
 def test_install_only_dependencies(tmpdir, mock_fetch, install_mockery):
-    dep = Spec("dependency-install").concretized()
-    root = Spec("dependent-install").concretized()
+    dep = spack.concretize.concretize_one("dependency-install")
+    root = spack.concretize.concretize_one("dependent-install")
 
     install("--only", "dependencies", "dependent-install")
 
@@ -714,8 +707,8 @@ def test_install_only_package(tmpdir, mock_fetch, install_mockery, capfd):
 
 
 def test_install_deps_then_package(tmpdir, mock_fetch, install_mockery):
-    dep = Spec("dependency-install").concretized()
-    root = Spec("dependent-install").concretized()
+    dep = spack.concretize.concretize_one("dependency-install")
+    root = spack.concretize.concretize_one("dependent-install")
 
     install("--only", "dependencies", "dependent-install")
     assert os.path.exists(dep.prefix)
@@ -733,8 +726,8 @@ def test_install_only_dependencies_in_env(
     env("create", "test")
 
     with ev.read("test"):
-        dep = Spec("dependency-install").concretized()
-        root = Spec("dependent-install").concretized()
+        dep = spack.concretize.concretize_one("dependency-install")
+        root = spack.concretize.concretize_one("dependent-install")
 
         install("-v", "--only", "dependencies", "--add", "dependent-install")
 
@@ -750,8 +743,8 @@ def test_install_only_dependencies_of_all_in_env(
 
     with ev.read("test"):
         roots = [
-            Spec("dependent-install@1.0").concretized(),
-            Spec("dependent-install@2.0").concretized(),
+            spack.concretize.concretize_one("dependent-install@1.0"),
+            spack.concretize.concretize_one("dependent-install@2.0"),
         ]
 
         add("dependent-install@1.0")
@@ -900,7 +893,7 @@ def test_cdash_configure_warning(tmpdir, mock_fetch, install_mockery, capfd):
 
         # Ensure that even on non-x86_64 architectures, there are no
         # dependencies installed
-        spec = Spec("configure-warning").concretized()
+        spec = spack.concretize.concretize_one("configure-warning")
         spec.clear_dependencies()
         specfile = "./spec.json"
         with open(specfile, "w", encoding="utf-8") as f:
@@ -946,7 +939,7 @@ def test_install_env_with_tests_all(
 ):
     env("create", "test")
     with ev.read("test"):
-        test_dep = Spec("test-dependency").concretized()
+        test_dep = spack.concretize.concretize_one("test-dependency")
         add("depb")
         install("--test", "all")
         assert os.path.exists(test_dep.prefix)
@@ -958,7 +951,7 @@ def test_install_env_with_tests_root(
 ):
     env("create", "test")
     with ev.read("test"):
-        test_dep = Spec("test-dependency").concretized()
+        test_dep = spack.concretize.concretize_one("test-dependency")
         add("depb")
         install("--test", "root")
         assert not os.path.exists(test_dep.prefix)

lib/spack/spack/test/cmd/load.py

@@ -7,7 +7,7 @@
 
 import pytest
 
-import spack.spec
+import spack.concretize
 import spack.user_environment as uenv
 from spack.main import SpackCommand
 
@@ -49,7 +49,7 @@ def test_load_shell(shell, set_command):
         """Test that `spack load` applies prefix inspections of its required runtime deps in
         topo-order"""
         install("mpileaks")
-        mpileaks_spec = spack.spec.Spec("mpileaks").concretized()
+        mpileaks_spec = spack.concretize.concretize_one("mpileaks")
 
         # Ensure our reference variable is clean.
         os.environ["CMAKE_PREFIX_PATH"] = "/hello" + os.pathsep + "/world"
@@ -166,7 +166,7 @@ def test_unload(
     """Tests that any variables set in the user environment are undone by the
     unload command"""
     install("mpileaks")
-    mpileaks_spec = spack.spec.Spec("mpileaks").concretized()
+    mpileaks_spec = spack.concretize.concretize_one("mpileaks")
 
     # Set so unload has something to do
     os.environ["FOOBAR"] = "mpileaks"
@@ -187,7 +187,7 @@ def test_unload_fails_no_shell(
 ):
     """Test that spack unload prints an error message without a shell."""
     install("mpileaks")
-    mpileaks_spec = spack.spec.Spec("mpileaks").concretized()
+    mpileaks_spec = spack.concretize.concretize_one("mpileaks")
     os.environ[uenv.spack_loaded_hashes_var] = mpileaks_spec.dag_hash()
 
     out = unload("mpileaks", fail_on_error=False)

lib/spack/spack/test/cmd/location.py

@@ -8,9 +8,9 @@
 
 from llnl.util.filesystem import mkdirp
 
+import spack.concretize
 import spack.environment as ev
 import spack.paths
-import spack.spec
 import spack.stage
 from spack.main import SpackCommand, SpackCommandError
 
@@ -25,7 +25,7 @@
 @pytest.fixture
 def mock_spec():
     # Make it look like the source was actually expanded.
-    s = spack.spec.Spec("externaltest").concretized()
+    s = spack.concretize.concretize_one("externaltest")
     source_path = s.package.stage.source_path
     mkdirp(source_path)
     yield s, s.package

lib/spack/spack/test/cmd/logs.py

@@ -13,6 +13,7 @@
 
 import spack
 import spack.cmd.logs
+import spack.concretize
 import spack.main
 import spack.spec
 from spack.main import SpackCommand
@@ -53,7 +54,7 @@ def disable_capture(capfd):
 
 
 def test_logs_cmd_errors(install_mockery, mock_fetch, mock_archive, mock_packages):
-    spec = spack.spec.Spec("libelf").concretized()
+    spec = spack.concretize.concretize_one("libelf")
     assert not spec.installed
 
     with pytest.raises(spack.main.SpackCommandError, match="is not installed or staged"):
@@ -82,7 +83,7 @@ def test_dump_logs(install_mockery, mock_fetch, mock_archive, mock_packages, dis
     decompress them.
     """
     cmdline_spec = spack.spec.Spec("libelf")
-    concrete_spec = cmdline_spec.concretized()
+    concrete_spec = spack.concretize.concretize_one(cmdline_spec)
 
     # Sanity check, make sure this test is checking what we want: to
     # start with

lib/spack/spack/test/cmd/mirror.py

@@ -7,6 +7,7 @@
 import pytest
 
 import spack.cmd.mirror
+import spack.concretize
 import spack.config
 import spack.environment as ev
 import spack.error
@@ -60,7 +61,7 @@ def test_mirror_from_env(tmp_path, mock_packages, mock_fetch, mutable_mock_env_p
 
 @pytest.fixture
 def source_for_pkg_with_hash(mock_packages, tmpdir):
-    s = spack.spec.Spec("trivial-pkg-with-valid-hash").concretized()
+    s = spack.concretize.concretize_one("trivial-pkg-with-valid-hash")
     local_url_basename = os.path.basename(s.package.url)
     local_path = os.path.join(str(tmpdir), local_url_basename)
     with open(local_path, "w", encoding="utf-8") as f:
@@ -72,7 +73,9 @@ def source_for_pkg_with_hash(mock_packages, tmpdir):
 def test_mirror_skip_unstable(tmpdir_factory, mock_packages, config, source_for_pkg_with_hash):
     mirror_dir = str(tmpdir_factory.mktemp("mirror-dir"))
 
-    specs = [spack.spec.Spec(x).concretized() for x in ["git-test", "trivial-pkg-with-valid-hash"]]
+    specs = [
+        spack.concretize.concretize_one(x) for x in ["git-test", "trivial-pkg-with-valid-hash"]
+    ]
     spack.mirrors.utils.create(mirror_dir, specs, skip_unstable_versions=True)
 
     assert set(os.listdir(mirror_dir)) - set(["_source-cache"]) == set(
@@ -111,7 +114,7 @@ def test_exclude_specs(mock_packages, config):
 
     mirror_specs, _ = spack.cmd.mirror._specs_and_action(args)
     expected_include = set(
-        spack.spec.Spec(x).concretized() for x in ["mpich@3.0.3", "mpich@3.0.4", "mpich@3.0"]
+        spack.concretize.concretize_one(x) for x in ["mpich@3.0.3", "mpich@3.0.4", "mpich@3.0"]
     )
     expected_exclude = set(spack.spec.Spec(x) for x in ["mpich@3.0.1", "mpich@3.0.2", "mpich@1.0"])
     assert expected_include <= set(mirror_specs)
@@ -145,7 +148,7 @@ def test_exclude_file(mock_packages, tmpdir, config):
 
     mirror_specs, _ = spack.cmd.mirror._specs_and_action(args)
     expected_include = set(
-        spack.spec.Spec(x).concretized() for x in ["mpich@3.0.3", "mpich@3.0.4", "mpich@3.0"]
+        spack.concretize.concretize_one(x) for x in ["mpich@3.0.3", "mpich@3.0.4", "mpich@3.0"]
     )
     expected_exclude = set(spack.spec.Spec(x) for x in ["mpich@3.0.1", "mpich@3.0.2", "mpich@1.0"])
     assert expected_include <= set(mirror_specs)

lib/spack/spack/test/cmd/module.py

@@ -7,12 +7,12 @@
 
 import pytest
 
+import spack.concretize
 import spack.config
 import spack.main
 import spack.modules
 import spack.modules.lmod
 import spack.repo
-import spack.spec
 import spack.store
 from spack.installer import PackageInstaller
 
@@ -33,7 +33,7 @@ def ensure_module_files_are_there(mock_repo_path, mock_store, mock_configuration
 
 
 def _module_files(module_type, *specs):
-    specs = [spack.spec.Spec(x).concretized() for x in specs]
+    specs = [spack.concretize.concretize_one(x) for x in specs]
     writer_cls = spack.modules.module_types[module_type]
     return [writer_cls(spec, "default").layout.filename for spec in specs]
 
@@ -184,12 +184,15 @@ def test_setdefault_command(mutable_database, mutable_config):
     # Install two different versions of pkg-a
     other_spec, preferred = "pkg-a@1.0", "pkg-a@2.0"
 
-    specs = [spack.spec.Spec(other_spec).concretized(), spack.spec.Spec(preferred).concretized()]
+    specs = [
+        spack.concretize.concretize_one(other_spec),
+        spack.concretize.concretize_one(preferred),
+    ]
     PackageInstaller([s.package for s in specs], explicit=True, fake=True).install()
 
     writers = {
-        preferred: writer_cls(spack.spec.Spec(preferred).concretized(), "default"),
-        other_spec: writer_cls(spack.spec.Spec(other_spec).concretized(), "default"),
+        preferred: writer_cls(specs[1], "default"),
+        other_spec: writer_cls(specs[0], "default"),
     }
 
     # Create two module files for the same software

lib/spack/spack/test/cmd/tags.py

@@ -2,9 +2,9 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
+import spack.concretize
 import spack.main
 import spack.repo
-import spack.spec
 from spack.installer import PackageInstaller
 
 tags = spack.main.SpackCommand("tags")
@@ -47,7 +47,7 @@ class tag_path:
 
 
 def test_tags_installed(install_mockery, mock_fetch):
-    s = spack.spec.Spec("mpich").concretized()
+    s = spack.concretize.concretize_one("mpich")
     PackageInstaller([s.package], explicit=True, fake=True).install()
 
     out = tags("-i")

lib/spack/spack/test/cmd/test.py

@@ -11,10 +11,10 @@
 
 import spack.cmd.common.arguments
 import spack.cmd.test
+import spack.concretize
 import spack.config
 import spack.install_test
 import spack.paths
-import spack.spec
 from spack.install_test import TestStatus
 from spack.main import SpackCommand
 
@@ -240,7 +240,7 @@ def test_read_old_results(mock_packages, mock_test_stage):
 
 def test_test_results_none(mock_packages, mock_test_stage):
     name = "trivial"
-    spec = spack.spec.Spec("trivial-smoke-test").concretized()
+    spec = spack.concretize.concretize_one("trivial-smoke-test")
     suite = spack.install_test.TestSuite([spec], name)
     suite.ensure_stage()
     spack.install_test.write_test_suite_file(suite)
@@ -255,7 +255,7 @@ def test_test_results_none(mock_packages, mock_test_stage):
 def test_test_results_status(mock_packages, mock_test_stage, status):
     """Confirm 'spack test results' returns expected status."""
     name = "trivial"
-    spec = spack.spec.Spec("trivial-smoke-test").concretized()
+    spec = spack.concretize.concretize_one("trivial-smoke-test")
     suite = spack.install_test.TestSuite([spec], name)
     suite.ensure_stage()
     spack.install_test.write_test_suite_file(suite)
@@ -278,7 +278,7 @@ def test_test_results_status(mock_packages, mock_test_stage, status):
 def test_report_filename_for_cdash(install_mockery, mock_fetch):
     """Test that the temporary file used to write Testing.xml for CDash is not the upload URL"""
     name = "trivial"
-    spec = spack.spec.Spec("trivial-smoke-test").concretized()
+    spec = spack.concretize.concretize_one("trivial-smoke-test")
     suite = spack.install_test.TestSuite([spec], name)
     suite.ensure_stage()
 

lib/spack/spack/test/cmd/undevelop.py

@@ -1,8 +1,8 @@
 # Copyright Spack Project Developers. See COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
+import spack.concretize
 import spack.environment as ev
-import spack.spec
 from spack.main import SpackCommand
 
 undevelop = SpackCommand("undevelop")
@@ -30,9 +30,9 @@ def test_undevelop(tmpdir, mutable_config, mock_packages, mutable_mock_env_path)
 
         env("create", "test", "./spack.yaml")
         with ev.read("test"):
-            before = spack.spec.Spec("mpich").concretized()
+            before = spack.concretize.concretize_one("mpich")
             undevelop("mpich")
-            after = spack.spec.Spec("mpich").concretized()
+            after = spack.concretize.concretize_one("mpich")
 
     # Removing dev spec from environment changes concretization
     assert before.satisfies("dev_path=*")

lib/spack/spack/test/cmd/verify.py

@@ -7,7 +7,7 @@
 
 import llnl.util.filesystem as fs
 
-import spack.spec
+import spack.concretize
 import spack.store
 import spack.util.spack_json as sjson
 import spack.verify
@@ -65,7 +65,7 @@ def test_single_file_verify_cmd(tmpdir):
 def test_single_spec_verify_cmd(tmpdir, mock_packages, mock_archive, mock_fetch, install_mockery):
     # Test the verify command interface to verify a single spec
     install("libelf")
-    s = spack.spec.Spec("libelf").concretized()
+    s = spack.concretize.concretize_one("libelf")
     prefix = s.prefix
     hash = s.dag_hash()
 

lib/spack/spack/test/cmd/view.py

@@ -9,10 +9,10 @@
 
 from llnl.util.symlink import _windows_can_symlink
 
+import spack.concretize
 import spack.util.spack_yaml as s_yaml
 from spack.installer import PackageInstaller
 from spack.main import SpackCommand
-from spack.spec import Spec
 
 extensions = SpackCommand("extensions")
 install = SpackCommand("install")
@@ -190,7 +190,7 @@ def test_view_fails_with_missing_projections_file(tmpdir):
 def test_view_files_not_ignored(
     tmpdir, mock_packages, mock_archive, mock_fetch, install_mockery, cmd, with_projection
 ):
-    spec = Spec("view-not-ignored").concretized()
+    spec = spack.concretize.concretize_one("view-not-ignored")
     pkg = spec.package
     PackageInstaller([pkg], explicit=True).install()
     pkg.assert_installed(spec.prefix)

lib/spack/spack/test/concretization/compiler_runtimes.py

@@ -8,6 +8,7 @@
 
 import archspec.cpu
 
+import spack.concretize
 import spack.config
 import spack.paths
 import spack.repo
@@ -20,7 +21,7 @@
 
 
 def _concretize_with_reuse(*, root_str, reused_str):
-    reused_spec = spack.spec.Spec(reused_str).concretized()
+    reused_spec = spack.concretize.concretize_one(reused_str)
     setup = spack.solver.asp.SpackSolverSetup(tests=False)
     driver = spack.solver.asp.PyclingoDriver()
     result, _, _ = driver.solve(setup, [spack.spec.Spec(f"{root_str}")], reuse=[reused_spec])
@@ -44,7 +45,7 @@ def enable_runtimes():
 
 
 def test_correct_gcc_runtime_is_injected_as_dependency(runtime_repo):
-    s = spack.spec.Spec("pkg-a%gcc@10.2.1 ^pkg-b%gcc@9.4.0").concretized()
+    s = spack.concretize.concretize_one("pkg-a%gcc@10.2.1 ^pkg-b%gcc@9.4.0")
     a, b = s["pkg-a"], s["pkg-b"]
 
     # Both a and b should depend on the same gcc-runtime directly
@@ -61,7 +62,7 @@ def test_external_nodes_do_not_have_runtimes(runtime_repo, mutable_config, tmp_p
     packages_yaml = {"pkg-b": {"externals": [{"spec": "pkg-b@1.0", "prefix": f"{str(tmp_path)}"}]}}
     spack.config.set("packages", packages_yaml)
 
-    s = spack.spec.Spec("pkg-a%gcc@10.2.1").concretized()
+    s = spack.concretize.concretize_one("pkg-a%gcc@10.2.1")
 
     a, b = s["pkg-a"], s["pkg-b"]
 

lib/spack/spack/test/concretization/errors.py

@@ -4,9 +4,9 @@
 
 import pytest
 
+import spack.concretize
 import spack.config
 import spack.solver.asp
-import spack.spec
 
 version_error_messages = [
     "Cannot satisfy 'fftw@:1.0' and 'fftw@1.1:",
@@ -57,7 +57,7 @@ def test_error_messages(error_messages, config_set, spec, mock_packages, mutable
         spack.config.set(path, conf)
 
     with pytest.raises(spack.solver.asp.UnsatisfiableSpecError) as e:
-        _ = spack.spec.Spec(spec).concretized()
+        _ = spack.concretize.concretize_one(spec)
 
     for em in error_messages:
         assert em in str(e.value)

lib/spack/spack/test/concretization/flag_mixing.py

@@ -5,12 +5,13 @@
 
 import pytest
 
+import spack.concretize
 import spack.config
 import spack.environment as ev
 import spack.paths
 import spack.repo
+import spack.spec
 import spack.util.spack_yaml as syaml
-from spack.spec import Spec
 
 """
 These tests include the following package DAGs:
@@ -62,12 +63,12 @@ def test_mix_spec_and_requirements(concretize_scope, test_repo):
 """
     update_concretize_scope(conf_str, "packages")
 
-    s1 = Spec('y cflags="-a"').concretized()
+    s1 = spack.concretize.concretize_one('y cflags="-a"')
     assert s1.satisfies('cflags="-a -c"')
 
 
 def test_mix_spec_and_dependent(concretize_scope, test_repo):
-    s1 = Spec('x ^y cflags="-a"').concretized()
+    s1 = spack.concretize.concretize_one('x ^y cflags="-a"')
     assert s1["y"].satisfies('cflags="-a -d1"')
 
 
@@ -92,10 +93,22 @@ def test_mix_spec_and_compiler_cfg(concretize_scope, test_repo):
     conf_str = _compiler_cfg_one_entry_with_cflags("-Wall")
     update_concretize_scope(conf_str, "compilers")
 
-    s1 = Spec('y %gcc@12.100.100 cflags="-O2"').concretized()
+    s1 = spack.concretize.concretize_one('y %gcc@12.100.100 cflags="-O2"')
     assert s1.satisfies('cflags="-Wall -O2"')
 
 
+def test_pkg_flags_from_compiler_and_none(concretize_scope, mock_packages):
+    conf_str = _compiler_cfg_one_entry_with_cflags("-Wall")
+    update_concretize_scope(conf_str, "compilers")
+
+    s1 = spack.spec.Spec("cmake%gcc@12.100.100")
+    s2 = spack.spec.Spec("cmake-client^cmake%clang")
+    concrete = dict(spack.concretize.concretize_together([(s1, None), (s2, None)]))
+
+    assert concrete[s1].compiler_flags["cflags"] == ["-Wall"]
+    assert concrete[s2].compiler_flags["cflags"] == []
+
+
 @pytest.mark.parametrize(
     "cmd_flags,req_flags,cmp_flags,dflags,expected_order",
     [
@@ -147,7 +160,7 @@ def test_flag_order_and_grouping(
     if cmd_flags:
         spec_str += f' cflags="{cmd_flags}"'
 
-    root_spec = Spec(spec_str).concretized()
+    root_spec = spack.concretize.concretize_one(spec_str)
     spec = root_spec["y"]
     satisfy_flags = " ".join(x for x in [cmd_flags, req_flags, cmp_flags, expected_dflags] if x)
     assert spec.satisfies(f'cflags="{satisfy_flags}"')
@@ -155,11 +168,11 @@ def test_flag_order_and_grouping(
 
 
 def test_two_dependents_flag_mixing(concretize_scope, test_repo):
-    root_spec1 = Spec("w~moveflaglater").concretized()
+    root_spec1 = spack.concretize.concretize_one("w~moveflaglater")
     spec1 = root_spec1["y"]
     assert spec1.compiler_flags["cflags"] == "-d0 -d1 -d2".split()
 
-    root_spec2 = Spec("w+moveflaglater").concretized()
+    root_spec2 = spack.concretize.concretize_one("w+moveflaglater")
     spec2 = root_spec2["y"]
     assert spec2.compiler_flags["cflags"] == "-d3 -d1 -d2".split()
 
@@ -168,7 +181,7 @@ def test_propagate_and_compiler_cfg(concretize_scope, test_repo):
     conf_str = _compiler_cfg_one_entry_with_cflags("-f2")
     update_concretize_scope(conf_str, "compilers")
 
-    root_spec = Spec("v %gcc@12.100.100 cflags=='-f1'").concretized()
+    root_spec = spack.concretize.concretize_one("v %gcc@12.100.100 cflags=='-f1'")
     assert root_spec["y"].satisfies("cflags='-f1 -f2'")
 
 
@@ -177,7 +190,7 @@ def test_propagate_and_compiler_cfg(concretize_scope, test_repo):
 
 
 def test_propagate_and_pkg_dep(concretize_scope, test_repo):
-    root_spec1 = Spec("x ~activatemultiflag cflags=='-f1'").concretized()
+    root_spec1 = spack.concretize.concretize_one("x ~activatemultiflag cflags=='-f1'")
     assert root_spec1["y"].satisfies("cflags='-f1 -d1'")
 
 
@@ -189,7 +202,7 @@ def test_propagate_and_require(concretize_scope, test_repo):
 """
     update_concretize_scope(conf_str, "packages")
 
-    root_spec1 = Spec("v cflags=='-f1'").concretized()
+    root_spec1 = spack.concretize.concretize_one("v cflags=='-f1'")
     assert root_spec1["y"].satisfies("cflags='-f1 -f2'")
 
     # Next, check that a requirement does not "undo" a request for
@@ -201,7 +214,7 @@ def test_propagate_and_require(concretize_scope, test_repo):
 """
     update_concretize_scope(conf_str, "packages")
 
-    root_spec2 = Spec("v cflags=='-f1'").concretized()
+    root_spec2 = spack.concretize.concretize_one("v cflags=='-f1'")
     assert root_spec2["y"].satisfies("cflags='-f1'")
 
     # Note: requirements cannot enforce propagation: any attempt to do
@@ -245,7 +258,7 @@ def test_diamond_dep_flag_mixing(concretize_scope, test_repo):
     nodes of the diamond always appear in the same order).
     `Spec.traverse` is responsible for handling both of these needs.
     """
-    root_spec1 = Spec("t").concretized()
+    root_spec1 = spack.concretize.concretize_one("t")
     spec1 = root_spec1["y"]
     assert spec1.satisfies('cflags="-c1 -c2 -d1 -d2 -e1 -e2"')
     assert spec1.compiler_flags["cflags"] == "-c1 -c2 -e1 -e2 -d1 -d2".split()

lib/spack/spack/test/concretization/preferences.py

@@ -7,6 +7,7 @@
 
 import pytest
 
+import spack.concretize
 import spack.config
 import spack.package_prefs
 import spack.repo
@@ -46,7 +47,7 @@ def configure_permissions():
 
 
 def concretize(abstract_spec):
-    return Spec(abstract_spec).concretized()
+    return spack.concretize.concretize_one(abstract_spec)
 
 
 def update_packages(pkgname, section, value):
@@ -111,7 +112,7 @@ def test_preferred_variants_from_wildcard(self):
     def test_preferred_compilers(self, compiler_str, spec_str):
         """Test preferred compilers are applied correctly"""
         update_packages("all", "compiler", [compiler_str])
-        spec = spack.spec.Spec(spec_str).concretized()
+        spec = spack.concretize.concretize_one(spec_str)
         assert spec.compiler == CompilerSpec(compiler_str)
 
     def test_preferred_target(self, mutable_mock_repo):
@@ -213,15 +214,13 @@ def test_config_set_pkg_property_new(self, mock_repo_path):
 
     def test_preferred(self):
         """ "Test packages with some version marked as preferred=True"""
-        spec = Spec("python")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("python")
         assert spec.version == Version("2.7.11")
 
         # now add packages.yaml with versions other than preferred
         # ensure that once config is in place, non-preferred version is used
         update_packages("python", "version", ["3.5.0"])
-        spec = Spec("python")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("python")
         assert spec.version == Version("3.5.0")
 
     def test_preferred_undefined_raises(self):
@@ -229,7 +228,7 @@ def test_preferred_undefined_raises(self):
         update_packages("python", "version", ["3.5.0.1"])
         spec = Spec("python")
         with pytest.raises(ConfigError):
-            spec.concretize()
+            spack.concretize.concretize_one(spec)
 
     def test_preferred_truncated(self):
         """Versions without "=" are treated as version ranges: if there is
@@ -237,35 +236,29 @@ def test_preferred_truncated(self):
         (don't define a new version).
         """
         update_packages("python", "version", ["3.5"])
-        spec = Spec("python")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("python")
         assert spec.satisfies("@3.5.1")
 
     def test_develop(self):
         """Test concretization with develop-like versions"""
-        spec = Spec("develop-test")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("develop-test")
         assert spec.version == Version("0.2.15")
-        spec = Spec("develop-test2")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("develop-test2")
         assert spec.version == Version("0.2.15")
 
         # now add packages.yaml with develop-like versions
         # ensure that once config is in place, develop-like version is used
         update_packages("develop-test", "version", ["develop"])
-        spec = Spec("develop-test")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("develop-test")
         assert spec.version == Version("develop")
 
         update_packages("develop-test2", "version", ["0.2.15.develop"])
-        spec = Spec("develop-test2")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("develop-test2")
         assert spec.version == Version("0.2.15.develop")
 
     def test_external_mpi(self):
         # make sure this doesn't give us an external first.
-        spec = Spec("mpi")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("mpi")
         assert not spec["mpi"].external
 
         # load config
@@ -284,8 +277,7 @@ def test_external_mpi(self):
         spack.config.set("packages", conf, scope="concretize")
 
         # ensure that once config is in place, external is used
-        spec = Spec("mpi")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("mpi")
         assert spec["mpich"].external_path == os.path.sep + os.path.join("dummy", "path")
 
     def test_external_module(self, monkeypatch):
@@ -300,8 +292,7 @@ def mock_module(cmd, module):
 
         monkeypatch.setattr(spack.util.module_cmd, "module", mock_module)
 
-        spec = Spec("mpi")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("mpi")
         assert not spec["mpi"].external
 
         # load config
@@ -320,8 +311,7 @@ def mock_module(cmd, module):
         spack.config.set("packages", conf, scope="concretize")
 
         # ensure that once config is in place, external is used
-        spec = Spec("mpi")
-        spec.concretize()
+        spec = spack.concretize.concretize_one("mpi")
         assert spec["mpich"].external_path == os.path.sep + os.path.join("dummy", "path")
 
     def test_buildable_false(self):
@@ -467,7 +457,7 @@ def test_variant_not_flipped_to_pull_externals(self):
         """Test that a package doesn't prefer pulling in an
         external to using the default value of a variant.
         """
-        s = Spec("vdefault-or-external-root").concretized()
+        s = spack.concretize.concretize_one("vdefault-or-external-root")
 
         assert "~external" in s["vdefault-or-external"]
         assert "externaltool" not in s
@@ -479,7 +469,7 @@ def test_dependencies_cant_make_version_parent_score_better(self):
         that makes the overall version score even or better and maybe
         has a better score in some lower priority criteria.
         """
-        s = Spec("version-test-root").concretized()
+        s = spack.concretize.concretize_one("version-test-root")
 
         assert s.satisfies("^version-test-pkg@2.4.6")
         assert "version-test-dependency-preferred" not in s
@@ -497,13 +487,13 @@ def test_multivalued_variants_are_lower_priority_than_providers(self):
         with spack.config.override(
             "packages:all", {"providers": {"somevirtual": ["some-virtual-preferred"]}}
         ):
-            s = Spec("somevirtual").concretized()
+            s = spack.concretize.concretize_one("somevirtual")
             assert s.name == "some-virtual-preferred"
 
     @pytest.mark.regression("26721,19736")
     def test_sticky_variant_accounts_for_packages_yaml(self):
         with spack.config.override("packages:sticky-variant", {"variants": "+allow-gcc"}):
-            s = Spec("sticky-variant %gcc").concretized()
+            s = spack.concretize.concretize_one("sticky-variant %gcc")
             assert s.satisfies("%gcc") and s.satisfies("+allow-gcc")
 
     @pytest.mark.regression("41134")
@@ -512,5 +502,5 @@ def test_default_preference_variant_different_type_does_not_error(self):
         packages.yaml doesn't fail with an error.
         """
         with spack.config.override("packages:all", {"variants": "+foo"}):
-            s = Spec("pkg-a").concretized()
+            s = spack.concretize.concretize_one("pkg-a")
             assert s.satisfies("foo=bar")

lib/spack/spack/test/concretization/requirements.py

@@ -6,6 +6,7 @@
 
 import pytest
 
+import spack.concretize
 import spack.config
 import spack.error
 import spack.package_base
@@ -42,7 +43,7 @@ def test_one_package_multiple_reqs(concretize_scope, test_repo):
     - "~shared"
 """
     update_packages_config(conf_str)
-    y_spec = Spec("y").concretized()
+    y_spec = spack.concretize.concretize_one("y")
     assert y_spec.satisfies("@2.4~shared")
 
 
@@ -57,7 +58,7 @@ def test_requirement_isnt_optional(concretize_scope, test_repo):
 """
     update_packages_config(conf_str)
     with pytest.raises(UnsatisfiableSpecError):
-        Spec("x@1.1").concretize()
+        spack.concretize.concretize_one("x@1.1")
 
 
 def test_require_undefined_version(concretize_scope, test_repo):
@@ -74,7 +75,7 @@ def test_require_undefined_version(concretize_scope, test_repo):
 """
     update_packages_config(conf_str)
     with pytest.raises(spack.error.ConfigError):
-        Spec("x").concretize()
+        spack.concretize.concretize_one("x")
 
 
 def test_require_truncated(concretize_scope, test_repo):
@@ -89,7 +90,7 @@ def test_require_truncated(concretize_scope, test_repo):
     require: "@1"
 """
     update_packages_config(conf_str)
-    xspec = Spec("x").concretized()
+    xspec = spack.concretize.concretize_one("x")
     assert xspec.satisfies("@1.1")
 
 
@@ -159,7 +160,7 @@ def test_requirement_adds_new_version(
     )
     update_packages_config(conf_str)
 
-    s1 = Spec("v").concretized()
+    s1 = spack.concretize.concretize_one("v")
     assert s1.satisfies("@2.2")
     # Make sure the git commit info is retained
     assert isinstance(s1.version, spack.version.GitVersion)
@@ -180,7 +181,7 @@ def test_requirement_adds_version_satisfies(
     )
 
     # Sanity check: early version of T does not include U
-    s0 = Spec("t@2.0").concretized()
+    s0 = spack.concretize.concretize_one("t@2.0")
     assert not ("u" in s0)
 
     conf_str = """\
@@ -192,7 +193,7 @@ def test_requirement_adds_version_satisfies(
     )
     update_packages_config(conf_str)
 
-    s1 = Spec("t").concretized()
+    s1 = spack.concretize.concretize_one("t")
     assert "u" in s1
     assert s1.satisfies("@2.2")
 
@@ -218,7 +219,7 @@ def test_requirement_adds_git_hash_version(
 """
     update_packages_config(conf_str)
 
-    s1 = Spec("v").concretized()
+    s1 = spack.concretize.concretize_one("v")
     assert isinstance(s1.version, spack.version.GitVersion)
     assert s1.satisfies(f"v@{a_commit_hash}")
 
@@ -239,8 +240,8 @@ def test_requirement_adds_multiple_new_versions(
 """
     update_packages_config(conf_str)
 
-    assert Spec("v").concretized().satisfies(f"@{commits[0]}=2.2")
-    assert Spec("v@2.3").concretized().satisfies(f"v@{commits[1]}=2.3")
+    assert spack.concretize.concretize_one("v").satisfies(f"@{commits[0]}=2.2")
+    assert spack.concretize.concretize_one("v@2.3").satisfies(f"v@{commits[1]}=2.3")
 
 
 # TODO: this belongs in the concretize_preferences test module but uses
@@ -263,11 +264,11 @@ def test_preference_adds_new_version(
 """
     update_packages_config(conf_str)
 
-    assert Spec("v").concretized().satisfies(f"@{commits[0]}=2.2")
-    assert Spec("v@2.3").concretized().satisfies(f"@{commits[1]}=2.3")
+    assert spack.concretize.concretize_one("v").satisfies(f"@{commits[0]}=2.2")
+    assert spack.concretize.concretize_one("v@2.3").satisfies(f"@{commits[1]}=2.3")
 
     # When installing by hash, a lookup is triggered, so it's not mapped to =2.3.
-    s3 = Spec(f"v@{commits[1]}").concretized()
+    s3 = spack.concretize.concretize_one(f"v@{commits[1]}")
     assert s3.satisfies(f"v@{commits[1]}")
     assert not s3.satisfies("@2.3")
 
@@ -287,7 +288,7 @@ def test_external_adds_new_version_that_is_preferred(concretize_scope, test_repo
 """
     update_packages_config(conf_str)
 
-    spec = Spec("x").concretized()
+    spec = spack.concretize.concretize_one("x")
     assert spec["y"].satisfies("@2.7")
     assert spack.version.Version("2.7") not in spec["y"].package.versions
 
@@ -296,7 +297,7 @@ def test_requirement_is_successfully_applied(concretize_scope, test_repo):
     """If a simple requirement can be satisfied, make sure the
     concretization succeeds and the requirement spec is applied.
     """
-    s1 = Spec("x").concretized()
+    s1 = spack.concretize.concretize_one("x")
     # Without any requirements/preferences, the later version is preferred
     assert s1.satisfies("@1.1")
 
@@ -306,7 +307,7 @@ def test_requirement_is_successfully_applied(concretize_scope, test_repo):
     require: "@1.0"
 """
     update_packages_config(conf_str)
-    s2 = Spec("x").concretized()
+    s2 = spack.concretize.concretize_one("x")
     # The requirement forces choosing the eariler version
     assert s2.satisfies("@1.0")
 
@@ -323,7 +324,7 @@ def test_multiple_packages_requirements_are_respected(concretize_scope, test_rep
     require: "@2.4"
 """
     update_packages_config(conf_str)
-    spec = Spec("x").concretized()
+    spec = spack.concretize.concretize_one("x")
     assert spec["x"].satisfies("@1.0")
     assert spec["y"].satisfies("@2.4")
 
@@ -339,7 +340,7 @@ def test_oneof(concretize_scope, test_repo):
     - one_of: ["@2.4", "~shared"]
 """
     update_packages_config(conf_str)
-    spec = Spec("x").concretized()
+    spec = spack.concretize.concretize_one("x")
     # The concretizer only has to satisfy one of @2.4/~shared, and @2.4
     # comes first so it is prioritized
     assert spec["y"].satisfies("@2.4+shared")
@@ -358,10 +359,10 @@ def test_one_package_multiple_oneof_groups(concretize_scope, test_repo):
 """
     update_packages_config(conf_str)
 
-    s1 = Spec("y@2.5").concretized()
+    s1 = spack.concretize.concretize_one("y@2.5")
     assert s1.satisfies("%clang~shared")
 
-    s2 = Spec("y@2.4").concretized()
+    s2 = spack.concretize.concretize_one("y@2.4")
     assert s2.satisfies("%gcc+shared")
 
 
@@ -377,10 +378,10 @@ def test_require_cflags(concretize_scope, mock_packages):
 """
     update_packages_config(conf_str)
 
-    spec_mpich2 = Spec("mpich2").concretized()
+    spec_mpich2 = spack.concretize.concretize_one("mpich2")
     assert spec_mpich2.satisfies("cflags=-g")
 
-    spec_mpi = Spec("mpi").concretized()
+    spec_mpi = spack.concretize.concretize_one("mpi")
     assert spec_mpi.satisfies("mpich cflags=-O1")
 
 
@@ -403,7 +404,7 @@ def test_requirements_for_package_that_is_not_needed(concretize_scope, test_repo
 """
     update_packages_config(conf_str)
 
-    s1 = Spec("v").concretized()
+    s1 = spack.concretize.concretize_one("v")
     assert s1.satisfies("@2.1")
 
 
@@ -420,10 +421,10 @@ def test_oneof_ordering(concretize_scope, test_repo):
 """
     update_packages_config(conf_str)
 
-    s1 = Spec("y").concretized()
+    s1 = spack.concretize.concretize_one("y")
     assert s1.satisfies("@2.4")
 
-    s2 = Spec("y@2.5").concretized()
+    s2 = spack.concretize.concretize_one("y@2.5")
     assert s2.satisfies("@2.5")
 
 
@@ -437,14 +438,14 @@ def test_reuse_oneof(concretize_scope, test_repo, tmp_path, mock_fetch):
 
     store_dir = tmp_path / "store"
     with spack.store.use_store(str(store_dir)):
-        s1 = Spec("y@2.5 ~shared").concretized()
+        s1 = spack.concretize.concretize_one("y@2.5~shared")
         PackageInstaller([s1.package], fake=True, explicit=True).install()
 
         update_packages_config(conf_str)
 
         with spack.config.override("concretizer:reuse", True):
-            s2 = Spec("y").concretized()
-            assert not s2.satisfies("@2.5 ~shared")
+            s2 = spack.concretize.concretize_one("y")
+            assert not s2.satisfies("@2.5~shared")
 
 
 @pytest.mark.parametrize(
@@ -472,7 +473,7 @@ def test_requirements_and_deprecated_versions(
     update_packages_config(conf_str)
 
     with spack.config.override("config:deprecated", allow_deprecated):
-        s1 = Spec("y").concretized()
+        s1 = spack.concretize.concretize_one("y")
         for constrain in expected:
             assert s1.satisfies(constrain)
 
@@ -490,7 +491,7 @@ def test_default_requirements_with_all(spec_str, requirement_str, concretize_sco
 """
     update_packages_config(conf_str)
 
-    spec = Spec(spec_str).concretized()
+    spec = spack.concretize.concretize_one(spec_str)
     for s in spec.traverse():
         assert s.satisfies(requirement_str)
 
@@ -499,7 +500,7 @@ def test_default_requirements_with_all(spec_str, requirement_str, concretize_sco
     "requirements,expectations",
     [
         (("%gcc", "%clang"), ("%gcc", "%clang")),
-        (("%gcc ~shared", "@1.0"), ("%gcc ~shared", "@1.0 +shared")),
+        (("%gcc~shared", "@1.0"), ("%gcc~shared", "@1.0+shared")),
     ],
 )
 def test_default_and_package_specific_requirements(
@@ -517,7 +518,7 @@ def test_default_and_package_specific_requirements(
 """
     update_packages_config(conf_str)
 
-    spec = Spec("x").concretized()
+    spec = spack.concretize.concretize_one("x")
     assert spec.satisfies(specific_exp)
     for s in spec.traverse(root=False):
         assert s.satisfies(generic_exp)
@@ -532,7 +533,7 @@ def test_requirements_on_virtual(mpi_requirement, concretize_scope, mock_package
 """
     update_packages_config(conf_str)
 
-    spec = Spec("callpath").concretized()
+    spec = spack.concretize.concretize_one("callpath")
     assert "mpi" in spec
     assert mpi_requirement in spec
 
@@ -553,7 +554,7 @@ def test_requirements_on_virtual_and_on_package(
 """
     update_packages_config(conf_str)
 
-    spec = Spec("callpath").concretized()
+    spec = spack.concretize.concretize_one("callpath")
     assert "mpi" in spec
     assert mpi_requirement in spec
     assert spec["mpi"].satisfies(specific_requirement)
@@ -567,10 +568,10 @@ def test_incompatible_virtual_requirements_raise(concretize_scope, mock_packages
     """
     update_packages_config(conf_str)
 
-    spec = Spec("callpath ^zmpi")
+    spec = Spec("callpath^zmpi")
     # TODO (multiple nodes): recover a better error message later
     with pytest.raises((UnsatisfiableSpecError, InternalConcretizerError)):
-        spec.concretize()
+        spack.concretize.concretize_one(spec)
 
 
 def test_non_existing_variants_under_all(concretize_scope, mock_packages):
@@ -582,7 +583,7 @@ def test_non_existing_variants_under_all(concretize_scope, mock_packages):
     """
     update_packages_config(conf_str)
 
-    spec = Spec("callpath ^zmpi").concretized()
+    spec = spack.concretize.concretize_one("callpath^zmpi")
     assert "~foo" not in spec
 
 
@@ -657,7 +658,7 @@ def test_conditional_requirements_from_packages_yaml(
     and optional when the condition is not met.
     """
     update_packages_config(packages_yaml)
-    spec = Spec(spec_str).concretized()
+    spec = spack.concretize.concretize_one(spec_str)
     for match_str, expected in expected_satisfies:
         assert spec.satisfies(match_str) is expected
 
@@ -733,7 +734,7 @@ def test_requirements_fail_with_custom_message(
     """
     update_packages_config(packages_yaml)
     with pytest.raises(spack.error.SpackError, match=expected_message):
-        Spec(spec_str).concretized()
+        spack.concretize.concretize_one(spec_str)
 
 
 def test_skip_requirement_when_default_requirement_condition_cannot_be_met(
@@ -752,9 +753,9 @@ def test_skip_requirement_when_default_requirement_condition_cannot_be_met(
               when: "+shared"
     """
     update_packages_config(packages_yaml)
-    s = Spec("mpileaks").concretized()
+    s = spack.concretize.concretize_one("mpileaks")
 
-    assert s.satisfies("%clang +shared")
+    assert s.satisfies("%clang+shared")
     # Sanity checks that 'callpath' doesn't have the shared variant, but that didn't
     # cause failures during concretization.
     assert "shared" not in s["callpath"].variants
@@ -781,12 +782,12 @@ def test_requires_directive(concretize_scope, mock_packages):
     spack.config.CONFIG.clear_caches()
 
     # This package requires either clang or gcc
-    s = Spec("requires_clang_or_gcc").concretized()
+    s = spack.concretize.concretize_one("requires_clang_or_gcc")
     assert s.satisfies("%gcc@12.0.0")
 
     # This package can only be compiled with clang
     with pytest.raises(spack.error.SpackError, match="can only be compiled with Clang"):
-        Spec("requires_clang").concretized()
+        spack.concretize.concretize_one("requires_clang")
 
 
 @pytest.mark.parametrize(
@@ -839,20 +840,20 @@ def test_default_requirements_semantic(packages_yaml, concretize_scope, mock_pac
     """
     update_packages_config(packages_yaml)
 
-    # Regular zlib concretize to +shared
-    s = Spec("zlib").concretized()
+    # Regular zlib concretize to+shared
+    s = spack.concretize.concretize_one("zlib")
     assert s.satisfies("+shared")
 
     # If we specify the variant we can concretize only the one matching the constraint
-    s = Spec("zlib +shared").concretized()
+    s = spack.concretize.concretize_one("zlib+shared")
     assert s.satisfies("+shared")
     with pytest.raises(UnsatisfiableSpecError):
-        Spec("zlib ~shared").concretized()
+        spack.concretize.concretize_one("zlib~shared")
 
     # A spec without the shared variant still concretize
-    s = Spec("pkg-a").concretized()
-    assert not s.satisfies("pkg-a +shared")
-    assert not s.satisfies("pkg-a ~shared")
+    s = spack.concretize.concretize_one("pkg-a")
+    assert not s.satisfies("pkg-a+shared")
+    assert not s.satisfies("pkg-a~shared")
 
 
 @pytest.mark.parametrize(
@@ -896,7 +897,7 @@ def test_default_requirements_semantic(packages_yaml, concretize_scope, mock_pac
             """
         packages:
           all:
-            require: "libs=static +feefoo"
+            require: "libs=static+feefoo"
     """,
             "multivalue-variant",
             ["libs=shared"],
@@ -911,7 +912,7 @@ def test_default_requirements_semantic_with_mv_variants(
     from MV variants.
     """
     update_packages_config(packages_yaml)
-    s = Spec(spec_str).concretized()
+    s = spack.concretize.concretize_one(spec_str)
 
     for constraint in expected:
         assert s.satisfies(constraint), constraint
@@ -936,7 +937,7 @@ def test_requiring_package_on_multiple_virtuals(concretize_scope, mock_packages)
         require: intel-parallel-studio
     """
     )
-    s = Spec("dla-future").concretized()
+    s = spack.concretize.concretize_one("dla-future")
 
     assert s["blas"].name == "intel-parallel-studio"
     assert s["lapack"].name == "intel-parallel-studio"
@@ -989,7 +990,7 @@ def test_strong_preferences_packages_yaml(
 ):
     """Tests that "preferred" specs are stronger than usual preferences, but can be overridden."""
     update_packages_config(packages_yaml)
-    s = Spec(spec_str).concretized()
+    s = spack.concretize.concretize_one(spec_str)
 
     for constraint in expected:
         assert s.satisfies(constraint), constraint
@@ -1038,29 +1039,29 @@ def test_conflict_packages_yaml(packages_yaml, spec_str, concretize_scope, mock_
     """Tests conflicts that are specified from configuration files."""
     update_packages_config(packages_yaml)
     with pytest.raises(UnsatisfiableSpecError):
-        Spec(spec_str).concretized()
+        spack.concretize.concretize_one(spec_str)
 
 
 @pytest.mark.parametrize(
     "spec_str,expected,not_expected",
     [
         (
-            "forward-multi-value +cuda cuda_arch=10 ^dependency-mv~cuda",
+            "forward-multi-value+cuda cuda_arch=10^dependency-mv~cuda",
             ["cuda_arch=10", "^dependency-mv~cuda"],
             ["cuda_arch=11", "^dependency-mv cuda_arch=10", "^dependency-mv cuda_arch=11"],
         ),
         (
-            "forward-multi-value +cuda cuda_arch=10 ^dependency-mv+cuda",
+            "forward-multi-value+cuda cuda_arch=10^dependency-mv+cuda",
             ["cuda_arch=10", "^dependency-mv cuda_arch=10"],
             ["cuda_arch=11", "^dependency-mv cuda_arch=11"],
         ),
         (
-            "forward-multi-value +cuda cuda_arch=11 ^dependency-mv+cuda",
+            "forward-multi-value+cuda cuda_arch=11^dependency-mv+cuda",
             ["cuda_arch=11", "^dependency-mv cuda_arch=11"],
             ["cuda_arch=10", "^dependency-mv cuda_arch=10"],
         ),
         (
-            "forward-multi-value +cuda cuda_arch=10,11 ^dependency-mv+cuda",
+            "forward-multi-value+cuda cuda_arch=10,11^dependency-mv+cuda",
             ["cuda_arch=10,11", "^dependency-mv cuda_arch=10,11"],
             [],
         ),
@@ -1073,9 +1074,9 @@ def test_forward_multi_valued_variant_using_requires(
     `requires` directives of the form:
 
         for _val in ("shared", "static"):
-            requires(f"^some-virtual-mv libs={_val}", when=f"libs={_val} ^some-virtual-mv")
+            requires(f"^some-virtual-mv libs={_val}", when=f"libs={_val}^some-virtual-mv")
     """
-    s = Spec(spec_str).concretized()
+    s = spack.concretize.concretize_one(spec_str)
 
     for constraint in expected:
         assert s.satisfies(constraint)
@@ -1086,7 +1087,7 @@ def test_forward_multi_valued_variant_using_requires(
 
 def test_strong_preferences_higher_priority_than_reuse(concretize_scope, mock_packages):
     """Tests that strong preferences have a higher priority than reusing specs."""
-    reused_spec = Spec("adios2~bzip2").concretized()
+    reused_spec = spack.concretize.concretize_one("adios2~bzip2")
     reuse_nodes = list(reused_spec.traverse())
     root_specs = [Spec("ascent+adios2")]
 
@@ -1121,7 +1122,7 @@ def test_strong_preferences_higher_priority_than_reuse(concretize_scope, mock_pa
         solver = spack.solver.asp.Solver()
         setup = spack.solver.asp.SpackSolverSetup()
         result, _, _ = solver.driver.solve(
-            setup, [Spec("ascent+adios2 ^adios2~bzip2")], reuse=reuse_nodes
+            setup, [Spec("ascent+adios2^adios2~bzip2")], reuse=reuse_nodes
         )
         ascent = result.specs[0]
     assert ascent["adios2"].dag_hash() == reused_spec.dag_hash(), ascent

lib/spack/spack/test/config_values.py

@@ -4,7 +4,7 @@
 
 import pytest
 
-import spack.spec
+import spack.concretize
 import spack.store
 
 
@@ -13,7 +13,7 @@
 def test_set_install_hash_length(hash_length, mutable_config, tmpdir):
     mutable_config.set("config:install_hash_length", hash_length)
     with spack.store.use_store(str(tmpdir)):
-        spec = spack.spec.Spec("libelf").concretized()
+        spec = spack.concretize.concretize_one("libelf")
         prefix = spec.prefix
         hash_str = prefix.rsplit("-")[-1]
         assert len(hash_str) == hash_length
@@ -23,7 +23,7 @@ def test_set_install_hash_length(hash_length, mutable_config, tmpdir):
 def test_set_install_hash_length_upper_case(mutable_config, tmpdir):
     mutable_config.set("config:install_hash_length", 5)
     with spack.store.use_store(str(tmpdir), extra_data={"projections": {"all": "{name}-{HASH}"}}):
-        spec = spack.spec.Spec("libelf").concretized()
+        spec = spack.concretize.concretize_one("libelf")
         prefix = spec.prefix
         hash_str = prefix.rsplit("-")[-1]
         assert len(hash_str) == 5

lib/spack/spack/test/conftest.py

@@ -36,6 +36,7 @@
 import spack.caches
 import spack.compiler
 import spack.compilers
+import spack.concretize
 import spack.config
 import spack.directives_meta
 import spack.environment as ev
@@ -635,11 +636,6 @@ def ensure_debug(monkeypatch):
     tty.set_debug(current_debug_level)
 
 
-@pytest.fixture(autouse=sys.platform == "win32", scope="session")
-def platform_config():
-    spack.config.add_default_platform_scope(spack.platforms.real_host().name)
-
-
 @pytest.fixture
 def default_config():
     """Isolates the default configuration from the user configs.
@@ -854,7 +850,7 @@ def _populate(mock_db):
     """
 
     def _install(spec):
-        s = spack.spec.Spec(spec).concretized()
+        s = spack.concretize.concretize_one(spec)
         PackageInstaller([s.package], fake=True, explicit=True).install()
 
     _install("mpileaks ^mpich")
@@ -892,21 +888,26 @@ def mock_store(
     """
     store_path, store_cache = _store_dir_and_cache
 
+    # Make the DB filesystem read-only to ensure constructors don't modify anything in it.
+    # We want Spack to be able to point to a DB on a read-only filesystem easily.
+    store_path.chmod(mode=0o555, rec=1)
+
     # If the cache does not exist populate the store and create it
     if not os.path.exists(str(store_cache.join(".spack-db"))):
         with spack.config.use_configuration(*mock_configuration_scopes):
             with spack.store.use_store(str(store_path)) as store:
                 with spack.repo.use_repositories(mock_repo_path):
+                    # make the DB filesystem writable only while we populate it
+                    store_path.chmod(mode=0o755, rec=1)
                     _populate(store.db)
-        copy_tree(str(store_path), str(store_cache))
+                    store_path.chmod(mode=0o555, rec=1)
 
-    # Make the DB filesystem read-only to ensure we can't modify entries
-    store_path.join(".spack-db").chmod(mode=0o555, rec=1)
+        store_cache.chmod(mode=0o755, rec=1)
+        copy_tree(str(store_path), str(store_cache))
+        store_cache.chmod(mode=0o555, rec=1)
 
     yield store_path
 
-    store_path.join(".spack-db").chmod(mode=0o755, rec=1)
-
 
 @pytest.fixture(scope="function")
 def database(mock_store, mock_packages, config):
@@ -932,7 +933,7 @@ def mutable_database(database_mutable_config, _store_dir_and_cache):
     """
     # Make the database writeable, as we are going to modify it
     store_path, store_cache = _store_dir_and_cache
-    store_path.join(".spack-db").chmod(mode=0o755, rec=1)
+    store_path.chmod(mode=0o755, rec=1)
 
     yield database_mutable_config
 
@@ -940,7 +941,7 @@ def mutable_database(database_mutable_config, _store_dir_and_cache):
     # the store and making the database read-only
     store_path.remove(rec=1)
     copy_tree(str(store_cache), str(store_path))
-    store_path.join(".spack-db").chmod(mode=0o555, rec=1)
+    store_path.chmod(mode=0o555, rec=1)
 
 
 @pytest.fixture()
@@ -1044,7 +1045,8 @@ def temporary_store(tmpdir, request):
     temporary_store_path = tmpdir.join("opt")
     with spack.store.use_store(str(temporary_store_path)) as s:
         yield s
-    temporary_store_path.remove()
+    if temporary_store_path.exists():
+        temporary_store_path.remove()
 
 
 @pytest.fixture()
@@ -1982,7 +1984,9 @@ def default_mock_concretization(config, mock_packages, concretized_specs_cache):
     def _func(spec_str, tests=False):
         key = spec_str, tests
         if key not in concretized_specs_cache:
-            concretized_specs_cache[key] = spack.spec.Spec(spec_str).concretized(tests=tests)
+            concretized_specs_cache[key] = spack.concretize.concretize_one(
+                spack.spec.Spec(spec_str), tests=tests
+            )
         return concretized_specs_cache[key].copy()
 
     return _func

lib/spack/spack/test/cvs_fetch.py

@@ -8,8 +8,8 @@
 
 from llnl.util.filesystem import mkdirp, touch, working_dir
 
+import spack.concretize
 from spack.fetch_strategy import CvsFetchStrategy
-from spack.spec import Spec
 from spack.stage import Stage
 from spack.util.executable import which
 from spack.version import Version
@@ -37,7 +37,7 @@ def test_fetch(type_of_test, mock_cvs_repository, config, mutable_mock_repo):
     get_date = mock_cvs_repository.get_date
 
     # Construct the package under test
-    spec = Spec("cvs-test").concretized()
+    spec = spack.concretize.concretize_one("cvs-test")
     spec.package.versions[Version("cvs")] = test.args
 
     # Enter the stage directory and check some properties

lib/spack/spack/test/database.py

@@ -2,10 +2,12 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 """Check the database is functioning properly, both in memory and in its file."""
+import contextlib
 import datetime
 import functools
 import json
 import os
+import pathlib
 import re
 import shutil
 import sys
@@ -26,12 +28,14 @@
 import llnl.util.lock as lk
 from llnl.util.tty.colify import colify
 
+import spack.concretize
 import spack.database
 import spack.deptypes as dt
 import spack.package_base
 import spack.repo
 import spack.spec
 import spack.store
+import spack.util.lock
 import spack.version as vn
 from spack.enums import InstallRecordStatus
 from spack.installer import PackageInstaller
@@ -41,24 +45,51 @@
 pytestmark = pytest.mark.db
 
 
+@contextlib.contextmanager
+def writable(database):
+    """Allow a database to be written inside this context manager."""
+    old_lock, old_is_upstream = database.lock, database.is_upstream
+    db_root = pathlib.Path(database.root)
+
+    try:
+        # this is safe on all platforms during tests (tests get their own tmpdirs)
+        database.lock = spack.util.lock.Lock(str(database._lock_path), enable=False)
+        database.is_upstream = False
+        db_root.chmod(mode=0o755)
+        with database.write_transaction():
+            yield
+    finally:
+        db_root.chmod(mode=0o555)
+        database.lock = old_lock
+        database.is_upstream = old_is_upstream
+
+
 @pytest.fixture()
 def upstream_and_downstream_db(tmpdir, gen_mock_layout):
-    mock_db_root = str(tmpdir.mkdir("mock_db_root"))
-    upstream_layout = gen_mock_layout("/a/")
-    upstream_write_db = spack.database.Database(mock_db_root, layout=upstream_layout)
-    upstream_db = spack.database.Database(mock_db_root, is_upstream=True, layout=upstream_layout)
-    # Generate initial DB file to avoid reindex
-    with open(upstream_write_db._index_path, "w", encoding="utf-8") as db_file:
-        upstream_write_db._write_to_file(db_file)
+    """Fixture for a pair of stores: upstream and downstream.
 
-    downstream_db_root = str(tmpdir.mkdir("mock_downstream_db_root"))
-    downstream_db = spack.database.Database(
-        downstream_db_root, upstream_dbs=[upstream_db], layout=gen_mock_layout("/b/")
+    Upstream API prohibits writing to an upstream, so we also return a writable version
+    of the upstream DB for tests to use.
+
+    """
+    mock_db_root = tmpdir.mkdir("mock_db_root")
+    mock_db_root.chmod(0o555)
+
+    upstream_db = spack.database.Database(
+        str(mock_db_root), is_upstream=True, layout=gen_mock_layout("/a/")
     )
-    with open(downstream_db._index_path, "w", encoding="utf-8") as db_file:
-        downstream_db._write_to_file(db_file)
+    with writable(upstream_db):
+        upstream_db._write()
 
-    yield upstream_write_db, upstream_db, downstream_db
+    downstream_db_root = tmpdir.mkdir("mock_downstream_db_root")
+    downstream_db_root.chmod(0o755)
+
+    downstream_db = spack.database.Database(
+        str(downstream_db_root), upstream_dbs=[upstream_db], layout=gen_mock_layout("/b/")
+    )
+    downstream_db._write()
+
+    yield upstream_db, downstream_db
 
 
 @pytest.mark.parametrize(
@@ -70,16 +101,18 @@ def upstream_and_downstream_db(tmpdir, gen_mock_layout):
         ("{u}", ["pkg-c"]),
         ("{d}", ["pkg-b"]),
     ],
+    ids=["all", "upstream", "local", "upstream_path", "downstream_path"],
 )
 def test_query_by_install_tree(
     install_tree, result, upstream_and_downstream_db, mock_packages, monkeypatch, config
 ):
-    up_write_db, up_db, down_db = upstream_and_downstream_db
+    up_db, down_db = upstream_and_downstream_db
 
     # Set the upstream DB to contain "pkg-c" and downstream to contain "pkg-b")
-    b = spack.spec.Spec("pkg-b").concretized()
-    c = spack.spec.Spec("pkg-c").concretized()
-    up_write_db.add(c)
+    b = spack.concretize.concretize_one("pkg-b")
+    c = spack.concretize.concretize_one("pkg-c")
+    with writable(up_db):
+        up_db.add(c)
     up_db._read()
     down_db.add(b)
 
@@ -91,15 +124,16 @@ def test_spec_installed_upstream(
     upstream_and_downstream_db, mock_custom_repository, config, monkeypatch
 ):
     """Test whether Spec.installed_upstream() works."""
-    upstream_write_db, upstream_db, downstream_db = upstream_and_downstream_db
+    upstream_db, downstream_db = upstream_and_downstream_db
 
     # a known installed spec should say that it's installed
     with spack.repo.use_repositories(mock_custom_repository):
-        spec = spack.spec.Spec("pkg-c").concretized()
+        spec = spack.concretize.concretize_one("pkg-c")
         assert not spec.installed
         assert not spec.installed_upstream
 
-        upstream_write_db.add(spec)
+        with writable(upstream_db):
+            upstream_db.add(spec)
         upstream_db._read()
 
         monkeypatch.setattr(spack.store.STORE, "db", downstream_db)
@@ -115,7 +149,7 @@ def test_spec_installed_upstream(
 
 @pytest.mark.usefixtures("config")
 def test_installed_upstream(upstream_and_downstream_db, tmpdir):
-    upstream_write_db, upstream_db, downstream_db = upstream_and_downstream_db
+    upstream_db, downstream_db = upstream_and_downstream_db
 
     builder = spack.repo.MockRepositoryBuilder(tmpdir.mkdir("mock.repo"))
     builder.add_package("x")
@@ -124,9 +158,10 @@ def test_installed_upstream(upstream_and_downstream_db, tmpdir):
     builder.add_package("w", dependencies=[("x", None, None), ("y", None, None)])
 
     with spack.repo.use_repositories(builder.root):
-        spec = spack.spec.Spec("w").concretized()
-        for dep in spec.traverse(root=False):
-            upstream_write_db.add(dep)
+        spec = spack.concretize.concretize_one("w")
+        with writable(upstream_db):
+            for dep in spec.traverse(root=False):
+                upstream_db.add(dep)
         upstream_db._read()
 
         for dep in spec.traverse(root=False):
@@ -135,7 +170,7 @@ def test_installed_upstream(upstream_and_downstream_db, tmpdir):
             with pytest.raises(spack.database.ForbiddenLockError):
                 upstream_db.get_by_hash(dep.dag_hash())
 
-        new_spec = spack.spec.Spec("w").concretized()
+        new_spec = spack.concretize.concretize_one("w")
         downstream_db.add(new_spec)
         for dep in new_spec.traverse(root=False):
             upstream, record = downstream_db.query_by_spec_hash(dep.dag_hash())
@@ -150,23 +185,25 @@ def test_installed_upstream(upstream_and_downstream_db, tmpdir):
 
 
 def test_removed_upstream_dep(upstream_and_downstream_db, tmpdir, capsys, config):
-    upstream_write_db, upstream_db, downstream_db = upstream_and_downstream_db
+    upstream_db, downstream_db = upstream_and_downstream_db
 
     builder = spack.repo.MockRepositoryBuilder(tmpdir.mkdir("mock.repo"))
     builder.add_package("z")
     builder.add_package("y", dependencies=[("z", None, None)])
 
     with spack.repo.use_repositories(builder):
-        y = spack.spec.Spec("y").concretized()
+        y = spack.concretize.concretize_one("y")
         z = y["z"]
 
         # add dependency to upstream, dependents to downstream
-        upstream_write_db.add(z)
+        with writable(upstream_db):
+            upstream_db.add(z)
         upstream_db._read()
         downstream_db.add(y)
 
         # remove the dependency from the upstream DB
-        upstream_write_db.remove(z)
+        with writable(upstream_db):
+            upstream_db.remove(z)
         upstream_db._read()
 
         # then rereading the downstream DB should warn about the missing dep
@@ -183,16 +220,17 @@ def test_add_to_upstream_after_downstream(upstream_and_downstream_db, tmpdir):
     DB. When a package is recorded as installed in both, the results should
     refer to the downstream DB.
     """
-    upstream_write_db, upstream_db, downstream_db = upstream_and_downstream_db
+    upstream_db, downstream_db = upstream_and_downstream_db
 
     builder = spack.repo.MockRepositoryBuilder(tmpdir.mkdir("mock.repo"))
     builder.add_package("x")
 
     with spack.repo.use_repositories(builder.root):
-        spec = spack.spec.Spec("x").concretized()
+        spec = spack.concretize.concretize_one("x")
 
         downstream_db.add(spec)
-        upstream_write_db.add(spec)
+        with writable(upstream_db):
+            upstream_db.add(spec)
         upstream_db._read()
 
         upstream, record = downstream_db.query_by_spec_hash(spec.dag_hash())
@@ -221,7 +259,7 @@ def test_cannot_write_upstream(tmp_path, mock_packages, config):
     db = spack.database.Database(str(tmp_path), is_upstream=True)
 
     with pytest.raises(spack.database.ForbiddenLockError):
-        db.add(spack.spec.Spec("pkg-a").concretized())
+        db.add(spack.concretize.concretize_one("pkg-a"))
 
 
 @pytest.mark.usefixtures("config", "temporary_store")
@@ -235,7 +273,7 @@ def test_recursive_upstream_dbs(tmpdir, gen_mock_layout):
     builder.add_package("x", dependencies=[("y", None, None)])
 
     with spack.repo.use_repositories(builder.root):
-        spec = spack.spec.Spec("x").concretized()
+        spec = spack.concretize.concretize_one("x")
         db_c = spack.database.Database(roots[2], layout=layouts[2])
         db_c.add(spec["z"])
 
@@ -385,7 +423,7 @@ def _check_remove_and_add_package(database: spack.database.Database, spec):
 
 
 def _mock_install(spec: str):
-    s = spack.spec.Spec(spec).concretized()
+    s = spack.concretize.concretize_one(spec)
     PackageInstaller([s.package], fake=True, explicit=True).install()
 
 
@@ -730,8 +768,7 @@ def test_regression_issue_8036(mutable_database, usr_folder_exists):
     # existing. Even when the package prefix exists, the package should
     # not be considered installed until it is added to the database by
     # the installer with install().
-    s = spack.spec.Spec("externaltool@0.9")
-    s.concretize()
+    s = spack.concretize.concretize_one("externaltool@0.9")
     assert not s.installed
 
     # Now install the external package and check again the `installed` property
@@ -746,8 +783,7 @@ def test_old_external_entries_prefix(mutable_database):
 
     jsonschema.validate(db_obj, schema)
 
-    s = spack.spec.Spec("externaltool")
-    s.concretize()
+    s = spack.concretize.concretize_one("externaltool")
 
     db_obj["database"]["installs"][s.dag_hash()]["path"] = "None"
 
@@ -776,8 +812,7 @@ def test_uninstall_by_spec(mutable_database):
 
 def test_query_unused_specs(mutable_database):
     # This spec installs a fake cmake as a build only dependency
-    s = spack.spec.Spec("simple-inheritance")
-    s.concretize()
+    s = spack.concretize.concretize_one("simple-inheritance")
     PackageInstaller([s.package], fake=True, explicit=True).install()
 
     si = s.dag_hash()
@@ -819,8 +854,7 @@ def check_unused(roots, deptype, expected):
 def test_query_spec_with_conditional_dependency(mutable_database):
     # The issue is triggered by having dependencies that are
     # conditional on a Boolean variant
-    s = spack.spec.Spec("hdf5~mpi")
-    s.concretize()
+    s = spack.concretize.concretize_one("hdf5~mpi")
     PackageInstaller([s.package], fake=True, explicit=True).install()
 
     results = spack.store.STORE.db.query_local("hdf5 ^mpich")
@@ -843,7 +877,7 @@ def test_query_virtual_spec(database):
     assert all(name in names for name in ["mpich", "mpich2", "zmpi"])
 
 
-def test_failed_spec_path_error(database):
+def test_failed_spec_path_error(mutable_database):
     """Ensure spec not concrete check is covered."""
     s = spack.spec.Spec("pkg-a")
     with pytest.raises(AssertionError, match="concrete spec required"):
@@ -860,7 +894,7 @@ def _is(self, spec):
     # Pretend the spec has been failure locked
     monkeypatch.setattr(spack.database.FailureTracker, "lock_taken", _is)
 
-    s = spack.spec.Spec("pkg-a").concretized()
+    s = spack.concretize.concretize_one("pkg-a")
     spack.store.STORE.failure_tracker.clear(s)
     out = capfd.readouterr()[0]
     assert "Retaining failure marking" in out
@@ -878,7 +912,7 @@ def _is(self, spec):
     # Ensure raise OSError when try to remove the non-existent marking
     monkeypatch.setattr(spack.database.FailureTracker, "persistent_mark", _is)
 
-    s = spack.spec.Spec("pkg-a").concretized()
+    s = spack.concretize.concretize_one("pkg-a")
     spack.store.STORE.failure_tracker.clear(s, force=True)
     out = capfd.readouterr()[1]
     assert "Removing failure marking despite lock" in out
@@ -893,7 +927,7 @@ def _raise_exc(lock):
         raise lk.LockTimeoutError("write", "/mock-lock", 1.234, 10)
 
     with tmpdir.as_cwd():
-        s = spack.spec.Spec("pkg-a").concretized()
+        s = spack.concretize.concretize_one("pkg-a")
 
         # Ensure attempt to acquire write lock on the mark raises the exception
         monkeypatch.setattr(lk.Lock, "acquire_write", _raise_exc)
@@ -909,7 +943,7 @@ def _raise_exc(lock):
 def test_prefix_failed(mutable_database, monkeypatch):
     """Add coverage to failed operation."""
 
-    s = spack.spec.Spec("pkg-a").concretized()
+    s = spack.concretize.concretize_one("pkg-a")
 
     # Confirm the spec is not already marked as failed
     assert not spack.store.STORE.failure_tracker.has_failed(s)
@@ -933,7 +967,7 @@ def test_prefix_write_lock_error(mutable_database, monkeypatch):
     def _raise(db, spec):
         raise lk.LockError("Mock lock error")
 
-    s = spack.spec.Spec("pkg-a").concretized()
+    s = spack.concretize.concretize_one("pkg-a")
 
     # Ensure subsequent lock operations fail
     monkeypatch.setattr(lk.Lock, "acquire_write", _raise)
@@ -950,7 +984,7 @@ def test_database_works_with_empty_dir(tmpdir):
     db_dir = tmpdir.ensure_dir(".spack-db")
     db_dir.ensure("lock")
     db_dir.ensure_dir("failures")
-    tmpdir.chmod(mode=0o555, rec=1)
+    tmpdir.chmod(mode=0o555)
     db = spack.database.Database(str(tmpdir))
     with db.read_transaction():
         db.query()
@@ -1105,6 +1139,8 @@ def test_error_message_when_using_too_new_db(database, monkeypatch):
 def test_database_construction_doesnt_use_globals(tmpdir, config, nullify_globals, lock_cfg):
     lock_cfg = lock_cfg or spack.database.lock_configuration(config)
     db = spack.database.Database(str(tmpdir), lock_cfg=lock_cfg)
+    with db.write_transaction():
+        pass  # ensure the DB is written
     assert os.path.exists(db.database_directory)
 
 
@@ -1125,15 +1161,13 @@ def test_database_read_works_with_trailing_data(tmp_path, default_mock_concretiz
     assert spack.database.Database(root).query_local() == specs_in_db
 
 
-def test_database_errors_with_just_a_version_key(tmp_path):
-    root = str(tmp_path)
-    db = spack.database.Database(root)
+def test_database_errors_with_just_a_version_key(mutable_database):
     next_version = f"{spack.database._DB_VERSION}.next"
-    with open(db._index_path, "w", encoding="utf-8") as f:
+    with open(mutable_database._index_path, "w", encoding="utf-8") as f:
         f.write(json.dumps({"database": {"version": next_version}}))
 
     with pytest.raises(spack.database.InvalidDatabaseVersionError):
-        spack.database.Database(root).query_local()
+        spack.database.Database(mutable_database.root).query_local()
 
 
 def test_reindex_with_upstreams(tmp_path, monkeypatch, mock_packages, config):
@@ -1141,7 +1175,7 @@ def test_reindex_with_upstreams(tmp_path, monkeypatch, mock_packages, config):
     # we install `mpileaks` locally with dependencies in the upstream. And we even install
     # `mpileaks` with the same hash in the upstream. After reindexing, `mpileaks` should still be
     # in the local db, and `callpath` should not.
-    mpileaks = spack.spec.Spec("mpileaks").concretized()
+    mpileaks = spack.concretize.concretize_one("mpileaks")
     callpath = mpileaks.dependencies("callpath")[0]
 
     upstream_store = spack.store.create(

lib/spack/spack/test/directives.py

@@ -5,6 +5,7 @@
 
 import pytest
 
+import spack.concretize
 import spack.directives
 import spack.repo
 import spack.spec
@@ -59,8 +60,8 @@ def test_constraints_from_context_are_merged(mock_packages):
 
 @pytest.mark.regression("27754")
 def test_extends_spec(config, mock_packages):
-    extender = spack.spec.Spec("extends-spec").concretized()
-    extendee = spack.spec.Spec("extendee").concretized()
+    extender = spack.concretize.concretize_one("extends-spec")
+    extendee = spack.concretize.concretize_one("extendee")
 
     assert extender.dependencies
     assert extender.package.extends(extendee)
@@ -206,7 +207,7 @@ def test_repo(_create_test_repo, monkeypatch, mock_stage):
 def test_redistribute_directive(test_repo, spec_str, distribute_src, distribute_bin):
     spec = spack.spec.Spec(spec_str)
     assert spec.package_class.redistribute_source(spec) == distribute_src
-    concretized_spec = spec.concretized()
+    concretized_spec = spack.concretize.concretize_one(spec)
     assert concretized_spec.package.redistribute_binary == distribute_bin
 
 

lib/spack/spack/test/directory_layout.py

@@ -13,6 +13,7 @@
 
 from llnl.path import path_to_os_path
 
+import spack.concretize
 import spack.hash_types
 import spack.paths
 import spack.repo
@@ -59,7 +60,7 @@ def test_yaml_directory_layout_parameters(tmpdir, default_mock_concretization):
     assert package7 == path_package7
 
     # Test separation of architecture or namespace
-    spec2 = Spec("libelf").concretized()
+    spec2 = spack.concretize.concretize_one("libelf")
 
     arch_scheme = (
         "{architecture.platform}/{architecture.target}/{architecture.os}/{name}/{version}/{hash:7}"
@@ -97,7 +98,7 @@ def test_read_and_write_spec(temporary_store, config, mock_packages):
         # If a spec fails to concretize, just skip it.  If it is a
         # real error, it will be caught by concretization tests.
         try:
-            spec = spack.spec.Spec(name).concretized()
+            spec = spack.concretize.concretize_one(name)
         except Exception:
             continue
 
@@ -136,7 +137,7 @@ def test_read_and_write_spec(temporary_store, config, mock_packages):
         assert norm.eq_dag(spec_from_file)
 
         # TODO: revise this when build deps are in dag_hash
-        conc = read_separately.concretized().copy(deps=stored_deptypes)
+        conc = spack.concretize.concretize_one(read_separately).copy(deps=stored_deptypes)
         assert conc == spec_from_file
         assert conc.eq_dag(spec_from_file)
 
@@ -172,12 +173,10 @@ def test_handle_unknown_package(temporary_store, config, mock_packages, tmp_path
     # Create all the packages that are not in mock.
     installed_specs = {}
     for pkg_name in packages:
-        spec = spack.spec.Spec(pkg_name)
-
         # If a spec fails to concretize, just skip it.  If it is a
         # real error, it will be caught by concretization tests.
         try:
-            spec.concretize()
+            spec = spack.concretize.concretize_one(pkg_name)
         except Exception:
             continue
 
@@ -209,7 +208,7 @@ def test_find(temporary_store, config, mock_packages):
         if name.startswith("external"):
             # External package tests cannot be installed
             continue
-        spec = spack.spec.Spec(name).concretized()
+        spec = spack.concretize.concretize_one(name)
         installed_specs[spec.name] = spec
         layout.create_install_directory(spec)
 

lib/spack/spack/test/flag_handlers.py

@@ -7,7 +7,7 @@
 import pytest
 
 import spack.build_environment
-import spack.spec
+import spack.concretize
 from spack.package import build_system_flags, env_flags, inject_flags
 
 
@@ -30,10 +30,10 @@ def add_o3_to_build_system_cflags(pkg, name, flags):
 class TestFlagHandlers:
     def test_no_build_system_flags(self, temp_env):
         # Test that both autotools and cmake work getting no build_system flags
-        s1 = spack.spec.Spec("cmake-client").concretized()
+        s1 = spack.concretize.concretize_one("cmake-client")
         spack.build_environment.setup_package(s1.package, False)
 
-        s2 = spack.spec.Spec("patchelf").concretized()
+        s2 = spack.concretize.concretize_one("patchelf")
         spack.build_environment.setup_package(s2.package, False)
 
         # Use cppflags as a canary
@@ -43,28 +43,28 @@ def test_no_build_system_flags(self, temp_env):
     def test_unbound_method(self, temp_env):
         # Other tests test flag_handlers set as bound methods and functions.
         # This tests an unbound method in python2 (no change in python3).
-        s = spack.spec.Spec("mpileaks cppflags=-g").concretized()
+        s = spack.concretize.concretize_one("mpileaks cppflags=-g")
         s.package.flag_handler = s.package.__class__.inject_flags
         spack.build_environment.setup_package(s.package, False)
         assert os.environ["SPACK_CPPFLAGS"] == "-g"
         assert "CPPFLAGS" not in os.environ
 
     def test_inject_flags(self, temp_env):
-        s = spack.spec.Spec("mpileaks cppflags=-g").concretized()
+        s = spack.concretize.concretize_one("mpileaks cppflags=-g")
         s.package.flag_handler = inject_flags
         spack.build_environment.setup_package(s.package, False)
         assert os.environ["SPACK_CPPFLAGS"] == "-g"
         assert "CPPFLAGS" not in os.environ
 
     def test_env_flags(self, temp_env):
-        s = spack.spec.Spec("mpileaks cppflags=-g").concretized()
+        s = spack.concretize.concretize_one("mpileaks cppflags=-g")
         s.package.flag_handler = env_flags
         spack.build_environment.setup_package(s.package, False)
         assert os.environ["CPPFLAGS"] == "-g"
         assert "SPACK_CPPFLAGS" not in os.environ
 
     def test_build_system_flags_cmake(self, temp_env):
-        s = spack.spec.Spec("cmake-client cppflags=-g").concretized()
+        s = spack.concretize.concretize_one("cmake-client cppflags=-g")
         s.package.flag_handler = build_system_flags
         spack.build_environment.setup_package(s.package, False)
         assert "SPACK_CPPFLAGS" not in os.environ
@@ -76,7 +76,7 @@ def test_build_system_flags_cmake(self, temp_env):
         }
 
     def test_build_system_flags_autotools(self, temp_env):
-        s = spack.spec.Spec("patchelf cppflags=-g").concretized()
+        s = spack.concretize.concretize_one("patchelf cppflags=-g")
         s.package.flag_handler = build_system_flags
         spack.build_environment.setup_package(s.package, False)
         assert "SPACK_CPPFLAGS" not in os.environ
@@ -85,7 +85,7 @@ def test_build_system_flags_autotools(self, temp_env):
 
     def test_build_system_flags_not_implemented(self, temp_env):
         """Test the command line flags method raises a NotImplementedError"""
-        s = spack.spec.Spec("mpileaks cppflags=-g").concretized()
+        s = spack.concretize.concretize_one("mpileaks cppflags=-g")
         s.package.flag_handler = build_system_flags
         try:
             spack.build_environment.setup_package(s.package, False)
@@ -94,7 +94,7 @@ def test_build_system_flags_not_implemented(self, temp_env):
             assert True
 
     def test_add_build_system_flags_autotools(self, temp_env):
-        s = spack.spec.Spec("patchelf cppflags=-g").concretized()
+        s = spack.concretize.concretize_one("patchelf cppflags=-g")
         s.package.flag_handler = add_o3_to_build_system_cflags
         spack.build_environment.setup_package(s.package, False)
         assert "-g" in os.environ["SPACK_CPPFLAGS"]
@@ -102,7 +102,7 @@ def test_add_build_system_flags_autotools(self, temp_env):
         assert s.package.configure_flag_args == ["CFLAGS=-O3"]
 
     def test_add_build_system_flags_cmake(self, temp_env):
-        s = spack.spec.Spec("cmake-client cppflags=-g").concretized()
+        s = spack.concretize.concretize_one("cmake-client cppflags=-g")
         s.package.flag_handler = add_o3_to_build_system_cflags
         spack.build_environment.setup_package(s.package, False)
         assert "-g" in os.environ["SPACK_CPPFLAGS"]
@@ -110,7 +110,7 @@ def test_add_build_system_flags_cmake(self, temp_env):
         assert s.package.cmake_flag_args == ["-DCMAKE_C_FLAGS=-O3"]
 
     def test_ld_flags_cmake(self, temp_env):
-        s = spack.spec.Spec("cmake-client ldflags=-mthreads").concretized()
+        s = spack.concretize.concretize_one("cmake-client ldflags=-mthreads")
         s.package.flag_handler = build_system_flags
         spack.build_environment.setup_package(s.package, False)
         assert "SPACK_LDFLAGS" not in os.environ
@@ -122,7 +122,7 @@ def test_ld_flags_cmake(self, temp_env):
         }
 
     def test_ld_libs_cmake(self, temp_env):
-        s = spack.spec.Spec("cmake-client ldlibs=-lfoo").concretized()
+        s = spack.concretize.concretize_one("cmake-client ldlibs=-lfoo")
         s.package.flag_handler = build_system_flags
         spack.build_environment.setup_package(s.package, False)
         assert "SPACK_LDLIBS" not in os.environ
@@ -138,7 +138,7 @@ def test_flag_handler(self, name, flags):
             flags.append("-foo")
             return (flags, None, None)
 
-        s = spack.spec.Spec("cmake-client").concretized()
+        s = spack.concretize.concretize_one("cmake-client")
         s.package.flag_handler = test_flag_handler
         spack.build_environment.setup_package(s.package, False)
 

lib/spack/spack/test/git_fetch.py

@@ -10,6 +10,7 @@
 
 from llnl.util.filesystem import mkdirp, touch, working_dir
 
+import spack.concretize
 import spack.config
 import spack.error
 import spack.fetch_strategy
@@ -185,8 +186,9 @@ def test_adhoc_version_submodules(
     monkeypatch.setitem(pkg_class.versions, Version("git"), t.args)
     monkeypatch.setattr(pkg_class, "git", "file://%s" % mock_git_repository.path, raising=False)
 
-    spec = Spec("git-test@{0}".format(mock_git_repository.unversioned_commit))
-    spec.concretize()
+    spec = spack.concretize.concretize_one(
+        Spec("git-test@{0}".format(mock_git_repository.unversioned_commit))
+    )
     spec.package.do_stage()
     collected_fnames = set()
     for root, dirs, files in os.walk(spec.package.stage.source_path):

lib/spack/spack/test/graph.py

@@ -3,8 +3,8 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 import io
 
+import spack.concretize
 import spack.graph
-import spack.spec
 
 
 def test_dynamic_dot_graph_mpileaks(default_mock_concretization):
@@ -38,7 +38,7 @@ def test_dynamic_dot_graph_mpileaks(default_mock_concretization):
 
 def test_ascii_graph_mpileaks(config, mock_packages, monkeypatch):
     monkeypatch.setattr(spack.graph.AsciiGraph, "_node_label", lambda self, node: node.name)
-    s = spack.spec.Spec("mpileaks").concretized()
+    s = spack.concretize.concretize_one("mpileaks")
 
     stream = io.StringIO()
     graph = spack.graph.AsciiGraph()

lib/spack/spack/test/hg_fetch.py

@@ -8,9 +8,9 @@
 
 from llnl.util.filesystem import mkdirp, touch, working_dir
 
+import spack.concretize
 import spack.config
 from spack.fetch_strategy import HgFetchStrategy
-from spack.spec import Spec
 from spack.stage import Stage
 from spack.util.executable import which
 from spack.version import Version
@@ -40,7 +40,7 @@ def test_fetch(type_of_test, secure, mock_hg_repository, config, mutable_mock_re
     h = mock_hg_repository.hash
 
     # Construct the package under test
-    s = Spec("hg-test").concretized()
+    s = spack.concretize.concretize_one("hg-test")
     monkeypatch.setitem(s.package.versions, Version("hg"), t.args)
 
     # Enter the stage directory and check some properties

lib/spack/spack/test/install.py

@@ -11,6 +11,7 @@
 import llnl.util.filesystem as fs
 
 import spack.build_environment
+import spack.concretize
 import spack.config
 import spack.database
 import spack.error
@@ -41,7 +42,7 @@ def find_nothing(*args):
 
 
 def test_install_and_uninstall(install_mockery, mock_fetch, monkeypatch):
-    spec = Spec("trivial-install-test-package").concretized()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
 
     PackageInstaller([spec.package], explicit=True).install()
     assert spec.installed
@@ -53,7 +54,7 @@ def test_install_and_uninstall(install_mockery, mock_fetch, monkeypatch):
 @pytest.mark.regression("11870")
 def test_uninstall_non_existing_package(install_mockery, mock_fetch, monkeypatch):
     """Ensure that we can uninstall a package that has been deleted from the repo"""
-    spec = Spec("trivial-install-test-package").concretized()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
 
     PackageInstaller([spec.package], explicit=True).install()
     assert spec.installed
@@ -71,8 +72,7 @@ def test_uninstall_non_existing_package(install_mockery, mock_fetch, monkeypatch
 
 def test_pkg_attributes(install_mockery, mock_fetch, monkeypatch):
     # Get a basic concrete spec for the dummy package.
-    spec = Spec("attributes-foo-app ^attributes-foo")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("attributes-foo-app ^attributes-foo")
     assert spec.concrete
 
     pkg = spec.package
@@ -127,7 +127,7 @@ def remove_prefix(self):
 
 
 def test_partial_install_delete_prefix_and_stage(install_mockery, mock_fetch, working_env):
-    s = Spec("canfail").concretized()
+    s = spack.concretize.concretize_one("canfail")
 
     instance_rm_prefix = s.package.remove_prefix
 
@@ -157,7 +157,7 @@ def test_failing_overwrite_install_should_keep_previous_installation(
     the original install prefix instead of cleaning it.
     """
     # Do a successful install
-    s = Spec("canfail").concretized()
+    s = spack.concretize.concretize_one("canfail")
     s.package.set_install_succeed()
 
     # Do a failing overwrite install
@@ -173,13 +173,11 @@ def test_failing_overwrite_install_should_keep_previous_installation(
 
 
 def test_dont_add_patches_to_installed_package(install_mockery, mock_fetch, monkeypatch):
-    dependency = Spec("dependency-install")
-    dependency.concretize()
+    dependency = spack.concretize.concretize_one("dependency-install")
     PackageInstaller([dependency.package], explicit=True).install()
 
     dependency_hash = dependency.dag_hash()
-    dependent = Spec("dependent-install ^/" + dependency_hash)
-    dependent.concretize()
+    dependent = spack.concretize.concretize_one("dependent-install ^/" + dependency_hash)
 
     monkeypatch.setitem(
         dependency.package.patches,
@@ -191,20 +189,18 @@ def test_dont_add_patches_to_installed_package(install_mockery, mock_fetch, monk
 
 
 def test_installed_dependency_request_conflicts(install_mockery, mock_fetch, mutable_mock_repo):
-    dependency = Spec("dependency-install")
-    dependency.concretize()
+    dependency = spack.concretize.concretize_one("dependency-install")
     PackageInstaller([dependency.package], explicit=True).install()
 
     dependency_hash = dependency.dag_hash()
     dependent = Spec("conflicting-dependent ^/" + dependency_hash)
     with pytest.raises(spack.error.UnsatisfiableSpecError):
-        dependent.concretize()
+        spack.concretize.concretize_one(dependent)
 
 
 def test_install_dependency_symlinks_pkg(install_mockery, mock_fetch, mutable_mock_repo):
     """Test dependency flattening/symlinks mock package."""
-    spec = Spec("flatten-deps")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("flatten-deps")
     pkg = spec.package
     PackageInstaller([pkg], explicit=True).install()
 
@@ -215,7 +211,7 @@ def test_install_dependency_symlinks_pkg(install_mockery, mock_fetch, mutable_mo
 
 def test_install_times(install_mockery, mock_fetch, mutable_mock_repo):
     """Test install times added."""
-    spec = Spec("dev-build-test-install-phases").concretized()
+    spec = spack.concretize.concretize_one("dev-build-test-install-phases")
     PackageInstaller([spec.package], explicit=True).install()
 
     # Ensure dependency directory exists after the installation.
@@ -236,8 +232,7 @@ def test_flatten_deps(install_mockery, mock_fetch, mutable_mock_repo):
     """Explicitly test the flattening code for coverage purposes."""
     # Unfortunately, executing the 'flatten-deps' spec's installation does
     # not affect code coverage results, so be explicit here.
-    spec = Spec("dependent-install")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("dependent-install")
     pkg = spec.package
     PackageInstaller([pkg], explicit=True).install()
 
@@ -272,7 +267,7 @@ def install_upstream(tmpdir_factory, gen_mock_layout, install_mockery):
 
     def _install_upstream(*specs):
         for spec_str in specs:
-            prepared_db.add(Spec(spec_str).concretized())
+            prepared_db.add(spack.concretize.concretize_one(spec_str))
         downstream_root = str(tmpdir_factory.mktemp("mock_downstream_db_root"))
         return downstream_root, upstream_layout
 
@@ -285,8 +280,7 @@ def test_installed_upstream_external(install_upstream, mock_fetch):
     """
     store_root, _ = install_upstream("externaltool")
     with spack.store.use_store(store_root):
-        dependent = Spec("externaltest")
-        dependent.concretize()
+        dependent = spack.concretize.concretize_one("externaltest")
 
         new_dependency = dependent["externaltool"]
         assert new_dependency.external
@@ -304,8 +298,8 @@ def test_installed_upstream(install_upstream, mock_fetch):
     """
     store_root, upstream_layout = install_upstream("dependency-install")
     with spack.store.use_store(store_root):
-        dependency = Spec("dependency-install").concretized()
-        dependent = Spec("dependent-install").concretized()
+        dependency = spack.concretize.concretize_one("dependency-install")
+        dependent = spack.concretize.concretize_one("dependent-install")
 
         new_dependency = dependent["dependency-install"]
         assert new_dependency.installed_upstream
@@ -319,7 +313,7 @@ def test_installed_upstream(install_upstream, mock_fetch):
 
 @pytest.mark.disable_clean_stage_check
 def test_partial_install_keep_prefix(install_mockery, mock_fetch, monkeypatch, working_env):
-    s = Spec("canfail").concretized()
+    s = spack.concretize.concretize_one("canfail")
 
     # If remove_prefix is called at any point in this test, that is an error
     monkeypatch.setattr(spack.package_base.PackageBase, "remove_prefix", mock_remove_prefix)
@@ -336,7 +330,7 @@ def test_partial_install_keep_prefix(install_mockery, mock_fetch, monkeypatch, w
 
 
 def test_second_install_no_overwrite_first(install_mockery, mock_fetch, monkeypatch):
-    s = Spec("canfail").concretized()
+    s = spack.concretize.concretize_one("canfail")
     monkeypatch.setattr(spack.package_base.PackageBase, "remove_prefix", mock_remove_prefix)
 
     s.package.set_install_succeed()
@@ -356,8 +350,8 @@ def test_install_prefix_collision_fails(config, mock_fetch, mock_packages, tmpdi
     projections = {"projections": {"all": "one-prefix-per-package-{name}"}}
     with spack.store.use_store(str(tmpdir), extra_data=projections):
         with spack.config.override("config:checksum", False):
-            pkg_a = Spec("libelf@0.8.13").concretized().package
-            pkg_b = Spec("libelf@0.8.12").concretized().package
+            pkg_a = spack.concretize.concretize_one("libelf@0.8.13").package
+            pkg_b = spack.concretize.concretize_one("libelf@0.8.12").package
             PackageInstaller([pkg_a], explicit=True, fake=True).install()
 
             with pytest.raises(InstallError, match="Install prefix collision"):
@@ -365,14 +359,14 @@ def test_install_prefix_collision_fails(config, mock_fetch, mock_packages, tmpdi
 
 
 def test_store(install_mockery, mock_fetch):
-    spec = Spec("cmake-client").concretized()
+    spec = spack.concretize.concretize_one("cmake-client")
     pkg = spec.package
     PackageInstaller([pkg], fake=True, explicit=True).install()
 
 
 @pytest.mark.disable_clean_stage_check
 def test_failing_build(install_mockery, mock_fetch, capfd):
-    spec = Spec("failing-build").concretized()
+    spec = spack.concretize.concretize_one("failing-build")
     pkg = spec.package
 
     with pytest.raises(spack.build_environment.ChildError, match="Expected failure"):
@@ -387,8 +381,7 @@ def test_uninstall_by_spec_errors(mutable_database):
     """Test exceptional cases with the uninstall command."""
 
     # Try to uninstall a spec that has not been installed
-    spec = Spec("dependent-install")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("dependent-install")
     with pytest.raises(InstallError, match="is not installed"):
         PackageBase.uninstall_by_spec(spec)
 
@@ -401,7 +394,7 @@ def test_uninstall_by_spec_errors(mutable_database):
 @pytest.mark.disable_clean_stage_check
 def test_nosource_pkg_install(install_mockery, mock_fetch, mock_packages, capfd, ensure_debug):
     """Test install phases with the nosource package."""
-    spec = Spec("nosource").concretized()
+    spec = spack.concretize.concretize_one("nosource")
     pkg = spec.package
 
     # Make sure install works even though there is no associated code.
@@ -418,7 +411,7 @@ def test_nosource_bundle_pkg_install(
     install_mockery, mock_fetch, mock_packages, capfd, ensure_debug
 ):
     """Test install phases with the nosource-bundle package."""
-    spec = Spec("nosource-bundle").concretized()
+    spec = spack.concretize.concretize_one("nosource-bundle")
     pkg = spec.package
 
     # Make sure install works even though there is no associated code.
@@ -432,7 +425,7 @@ def test_nosource_bundle_pkg_install(
 
 def test_nosource_pkg_install_post_install(install_mockery, mock_fetch, mock_packages):
     """Test install phases with the nosource package with post-install."""
-    spec = Spec("nosource-install").concretized()
+    spec = spack.concretize.concretize_one("nosource-install")
     pkg = spec.package
 
     # Make sure both the install and post-install package methods work.
@@ -449,14 +442,14 @@ def test_nosource_pkg_install_post_install(install_mockery, mock_fetch, mock_pac
 
 def test_pkg_build_paths(install_mockery):
     # Get a basic concrete spec for the trivial install package.
-    spec = Spec("trivial-install-test-package").concretized()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
     assert spec.package.log_path.endswith(_spack_build_logfile)
     assert spec.package.env_path.endswith(_spack_build_envfile)
 
 
 def test_pkg_install_paths(install_mockery):
     # Get a basic concrete spec for the trivial install package.
-    spec = Spec("trivial-install-test-package").concretized()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
 
     log_path = os.path.join(spec.prefix, ".spack", _spack_build_logfile + ".gz")
     assert spec.package.install_log_path == log_path
@@ -493,7 +486,7 @@ def test_pkg_install_paths(install_mockery):
 def test_log_install_without_build_files(install_mockery):
     """Test the installer log function when no build files are present."""
     # Get a basic concrete spec for the trivial install package.
-    spec = Spec("trivial-install-test-package").concretized()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
 
     # Attempt installing log without the build log file
     with pytest.raises(IOError, match="No such file or directory"):
@@ -515,7 +508,7 @@ def _install(src, dest):
 
     monkeypatch.setattr(fs, "install", _install)
 
-    spec = Spec("trivial-install-test-package").concretized()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
 
     # Set up mock build files and try again to include archive failure
     log_path = spec.package.log_path
@@ -587,7 +580,7 @@ def test_empty_install_sanity_check_prefix(
     monkeypatch, install_mockery, mock_fetch, mock_packages
 ):
     """Test empty install triggers sanity_check_prefix."""
-    spec = Spec("failing-empty-install").concretized()
+    spec = spack.concretize.concretize_one("failing-empty-install")
     with pytest.raises(spack.build_environment.ChildError, match="Nothing was installed"):
         PackageInstaller([spec.package], explicit=True).install()
 
@@ -599,7 +592,7 @@ def test_install_from_binary_with_missing_patch_succeeds(
     pushing the package to a binary cache, installation from that binary cache shouldn't error out
     because of the missing patch."""
     # Create a spec s with non-existing patches
-    s = Spec("trivial-install-test-package").concretized()
+    s = spack.concretize.concretize_one("trivial-install-test-package")
     patches = ["a" * 64]
     s_dict = s.to_dict()
     s_dict["spec"]["nodes"][0]["patches"] = patches

lib/spack/spack/test/installer.py

@@ -16,6 +16,7 @@
 import llnl.util.tty as tty
 
 import spack.binary_distribution
+import spack.concretize
 import spack.database
 import spack.deptypes as dt
 import spack.error
@@ -81,7 +82,7 @@ def create_installer(
 ) -> inst.PackageInstaller:
     """Create an installer instance for a list of specs or package names that will be
     concretized."""
-    _specs = [spack.spec.Spec(s).concretized() if isinstance(s, str) else s for s in specs]
+    _specs = [spack.concretize.concretize_one(s) if isinstance(s, str) else s for s in specs]
     _install_args = {} if install_args is None else install_args
     return inst.PackageInstaller([spec.package for spec in _specs], **_install_args)
 
@@ -96,8 +97,7 @@ def test_hms(sec, result):
 
 def test_get_dependent_ids(install_mockery, mock_packages):
     # Concretize the parent package, which handle dependency too
-    spec = spack.spec.Spec("pkg-a")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("pkg-a")
     assert spec.concrete
 
     pkg_id = inst.package_id(spec)
@@ -133,8 +133,7 @@ def test_install_msg(monkeypatch):
 
 def test_install_from_cache_errors(install_mockery):
     """Test to ensure cover install from cache errors."""
-    spec = spack.spec.Spec("trivial-install-test-package")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
     assert spec.concrete
 
     # Check with cache-only
@@ -153,8 +152,7 @@ def test_install_from_cache_errors(install_mockery):
 
 def test_install_from_cache_ok(install_mockery, monkeypatch):
     """Test to ensure cover _install_from_cache to the return."""
-    spec = spack.spec.Spec("trivial-install-test-package")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
     monkeypatch.setattr(inst, "_try_install_from_binary_cache", _true)
     monkeypatch.setattr(spack.hooks, "post_install", _noop)
 
@@ -163,8 +161,7 @@ def test_install_from_cache_ok(install_mockery, monkeypatch):
 
 def test_process_external_package_module(install_mockery, monkeypatch, capfd):
     """Test to simply cover the external module message path."""
-    spec = spack.spec.Spec("trivial-install-test-package")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
     assert spec.concrete
 
     # Ensure take the external module path WITHOUT any changes to the database
@@ -191,7 +188,7 @@ def _spec(spec, unsigned=False, mirrors_for_spec=None):
     # Skip database updates
     monkeypatch.setattr(spack.database.Database, "add", _noop)
 
-    spec = spack.spec.Spec("pkg-a").concretized()
+    spec = spack.concretize.concretize_one("pkg-a")
     assert inst._process_binary_cache_tarball(spec.package, explicit=False, unsigned=False)
 
     out = capfd.readouterr()[0]
@@ -201,8 +198,7 @@ def _spec(spec, unsigned=False, mirrors_for_spec=None):
 
 def test_try_install_from_binary_cache(install_mockery, mock_packages, monkeypatch):
     """Test return false when no match exists in the mirror"""
-    spec = spack.spec.Spec("mpich")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("mpich")
     result = inst._try_install_from_binary_cache(spec.package, False, False)
     assert not result
 
@@ -274,7 +270,7 @@ def _mock_installed(self):
 
 
 def test_check_before_phase_error(install_mockery):
-    s = spack.spec.Spec("trivial-install-test-package").concretized()
+    s = spack.concretize.concretize_one("trivial-install-test-package")
     s.package.stop_before_phase = "beforephase"
     with pytest.raises(inst.BadInstallPhase) as exc_info:
         inst._check_last_phase(s.package)
@@ -285,7 +281,7 @@ def test_check_before_phase_error(install_mockery):
 
 
 def test_check_last_phase_error(install_mockery):
-    s = spack.spec.Spec("trivial-install-test-package").concretized()
+    s = spack.concretize.concretize_one("trivial-install-test-package")
     s.package.stop_before_phase = None
     s.package.last_phase = "badphase"
     with pytest.raises(inst.BadInstallPhase) as exc_info:
@@ -420,15 +416,13 @@ def test_package_id_err(install_mockery):
 
 
 def test_package_id_ok(install_mockery):
-    spec = spack.spec.Spec("trivial-install-test-package")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
     assert spec.concrete
     assert spec.name in inst.package_id(spec)
 
 
 def test_fake_install(install_mockery):
-    spec = spack.spec.Spec("trivial-install-test-package")
-    spec.concretize()
+    spec = spack.concretize.concretize_one("trivial-install-test-package")
     assert spec.concrete
 
     pkg = spec.package
@@ -440,7 +434,7 @@ def test_dump_packages_deps_ok(install_mockery, tmpdir, mock_packages):
     """Test happy path for dump_packages with dependencies."""
 
     spec_name = "simple-inheritance"
-    spec = spack.spec.Spec(spec_name).concretized()
+    spec = spack.concretize.concretize_one(spec_name)
     inst.dump_packages(spec, str(tmpdir))
 
     repo = mock_packages.repos[0]
@@ -471,7 +465,7 @@ def _repoerr(repo, name):
     # the try-except block
     monkeypatch.setattr(spack.store.STORE.layout, "build_packages_path", bpp_path)
 
-    spec = spack.spec.Spec("simple-inheritance").concretized()
+    spec = spack.concretize.concretize_one("simple-inheritance")
     path = str(tmpdir)
 
     # The call to install_tree will raise the exception since not mocking
@@ -581,7 +575,7 @@ def test_check_deps_status_install_failure(install_mockery):
     """Tests that checking the dependency status on a request to install
     'a' fails, if we mark the dependency as failed.
     """
-    s = spack.spec.Spec("pkg-a").concretized()
+    s = spack.concretize.concretize_one("pkg-a")
     for dep in s.traverse(root=False):
         spack.store.STORE.failure_tracker.mark(dep)
 
@@ -654,8 +648,8 @@ def test_installer_init_requests(install_mockery):
 @pytest.mark.parametrize("transitive", [True, False])
 def test_install_spliced(install_mockery, mock_fetch, monkeypatch, capsys, transitive):
     """Test installing a spliced spec"""
-    spec = spack.spec.Spec("splice-t").concretized()
-    dep = spack.spec.Spec("splice-h+foo").concretized()
+    spec = spack.concretize.concretize_one("splice-t")
+    dep = spack.concretize.concretize_one("splice-h+foo")
 
     # Do the splice.
     out = spec.splice(dep, transitive)
@@ -669,8 +663,8 @@ def test_install_spliced(install_mockery, mock_fetch, monkeypatch, capsys, trans
 @pytest.mark.parametrize("transitive", [True, False])
 def test_install_spliced_build_spec_installed(install_mockery, capfd, mock_fetch, transitive):
     """Test installing a spliced spec with the build spec already installed"""
-    spec = spack.spec.Spec("splice-t").concretized()
-    dep = spack.spec.Spec("splice-h+foo").concretized()
+    spec = spack.concretize.concretize_one("splice-t")
+    dep = spack.concretize.concretize_one("splice-h+foo")
 
     # Do the splice.
     out = spec.splice(dep, transitive)
@@ -696,8 +690,8 @@ def test_install_splice_root_from_binary(
 ):
     """Test installing a spliced spec with the root available in binary cache"""
     # Test splicing and rewiring a spec with the same name, different hash.
-    original_spec = spack.spec.Spec(root_str).concretized()
-    spec_to_splice = spack.spec.Spec("splice-h+foo").concretized()
+    original_spec = spack.concretize.concretize_one(root_str)
+    spec_to_splice = spack.concretize.concretize_one("splice-h+foo")
 
     PackageInstaller([original_spec.package, spec_to_splice.package]).install()
 
@@ -853,7 +847,7 @@ def _chgrp(path, group, follow_symlinks=True):
     monkeypatch.setattr(fs, "chgrp", _chgrp)
 
     build_task = create_build_task(
-        spack.spec.Spec("trivial-install-test-package").concretized().package
+        spack.concretize.concretize_one("trivial-install-test-package").package
     )
     spec = build_task.request.pkg.spec
 
@@ -1024,7 +1018,8 @@ def test_install_fail_multi(install_mockery, mock_fetch, monkeypatch):
 
 def test_install_fail_fast_on_detect(install_mockery, monkeypatch, capsys):
     """Test fail_fast install when an install failure is detected."""
-    b, c = spack.spec.Spec("pkg-b").concretized(), spack.spec.Spec("pkg-c").concretized()
+    b = spack.concretize.concretize_one("pkg-b")
+    c = spack.concretize.concretize_one("pkg-c")
     b_id, c_id = inst.package_id(b), inst.package_id(c)
 
     installer = create_installer([b, c], {"fail_fast": True})
@@ -1093,7 +1088,7 @@ def _requeued(installer, task, install_status):
 
 def test_install_lock_installed_requeue(install_mockery, monkeypatch, capfd):
     """Cover basic install handling for installed package."""
-    b = spack.spec.Spec("pkg-b").concretized()
+    b = spack.concretize.concretize_one("pkg-b")
     b_pkg_id = inst.package_id(b)
     installer = create_installer([b])
 
@@ -1279,7 +1274,7 @@ def test_term_status_line():
 @pytest.mark.parametrize("explicit", [True, False])
 def test_single_external_implicit_install(install_mockery, explicit):
     pkg = "trivial-install-test-package"
-    s = spack.spec.Spec(pkg).concretized()
+    s = spack.concretize.concretize_one(pkg)
     s.external_path = "/usr"
     args = {"explicit": [s.dag_hash()] if explicit else []}
     create_installer([s], args).install()
@@ -1288,7 +1283,7 @@ def test_single_external_implicit_install(install_mockery, explicit):
 
 def test_overwrite_install_does_install_build_deps(install_mockery, mock_fetch):
     """When overwrite installing something from sources, build deps should be installed."""
-    s = spack.spec.Spec("dtrun3").concretized()
+    s = spack.concretize.concretize_one("dtrun3")
     create_installer([s]).install()
 
     # Verify there is a pure build dep
@@ -1310,7 +1305,7 @@ def test_overwrite_install_does_install_build_deps(install_mockery, mock_fetch):
 def test_print_install_test_log_skipped(install_mockery, mock_packages, capfd, run_tests):
     """Confirm printing of install log skipped if not run/no failures."""
     name = "trivial-install-test-package"
-    s = spack.spec.Spec(name).concretized()
+    s = spack.concretize.concretize_one(name)
     pkg = s.package
 
     pkg.run_tests = run_tests
@@ -1324,7 +1319,7 @@ def test_print_install_test_log_failures(
 ):
     """Confirm expected outputs when there are test failures."""
     name = "trivial-install-test-package"
-    s = spack.spec.Spec(name).concretized()
+    s = spack.concretize.concretize_one(name)
     pkg = s.package
 
     # Missing test log is an error

lib/spack/spack/test/make_executable.py

@@ -29,31 +29,31 @@ def make_executable(tmp_path, working_env):
 
 
 def test_make_normal():
-    make = MakeExecutable("make", 8)
+    make = MakeExecutable("make", jobs=8)
     assert make(output=str).strip() == "-j8"
     assert make("install", output=str).strip() == "-j8 install"
 
 
 def test_make_explicit():
-    make = MakeExecutable("make", 8)
+    make = MakeExecutable("make", jobs=8)
     assert make(parallel=True, output=str).strip() == "-j8"
     assert make("install", parallel=True, output=str).strip() == "-j8 install"
 
 
 def test_make_one_job():
-    make = MakeExecutable("make", 1)
+    make = MakeExecutable("make", jobs=1)
     assert make(output=str).strip() == "-j1"
     assert make("install", output=str).strip() == "-j1 install"
 
 
 def test_make_parallel_false():
-    make = MakeExecutable("make", 8)
+    make = MakeExecutable("make", jobs=8)
     assert make(parallel=False, output=str).strip() == "-j1"
     assert make("install", parallel=False, output=str).strip() == "-j1 install"
 
 
 def test_make_parallel_disabled(monkeypatch):
-    make = MakeExecutable("make", 8)
+    make = MakeExecutable("make", jobs=8)
 
     monkeypatch.setenv("SPACK_NO_PARALLEL_MAKE", "true")
     assert make(output=str).strip() == "-j1"
@@ -74,7 +74,7 @@ def test_make_parallel_disabled(monkeypatch):
 
 
 def test_make_parallel_precedence(monkeypatch):
-    make = MakeExecutable("make", 8)
+    make = MakeExecutable("make", jobs=8)
 
     # These should work
     monkeypatch.setenv("SPACK_NO_PARALLEL_MAKE", "true")
@@ -96,21 +96,21 @@ def test_make_parallel_precedence(monkeypatch):
 
 
 def test_make_jobs_env():
-    make = MakeExecutable("make", 8)
+    make = MakeExecutable("make", jobs=8)
     dump_env = {}
     assert make(output=str, jobs_env="MAKE_PARALLELISM", _dump_env=dump_env).strip() == "-j8"
     assert dump_env["MAKE_PARALLELISM"] == "8"
 
 
 def test_make_jobserver(monkeypatch):
-    make = MakeExecutable("make", 8)
+    make = MakeExecutable("make", jobs=8)
     monkeypatch.setenv("MAKEFLAGS", "--jobserver-auth=X,Y")
     assert make(output=str).strip() == ""
     assert make(parallel=False, output=str).strip() == "-j1"
 
 
 def test_make_jobserver_not_supported(monkeypatch):
-    make = MakeExecutable("make", 8, supports_jobserver=False)
+    make = MakeExecutable("make", jobs=8, supports_jobserver=False)
     monkeypatch.setenv("MAKEFLAGS", "--jobserver-auth=X,Y")
     # Currently fallback on default job count, Maybe it should force -j1 ?
     assert make(output=str).strip() == "-j8"

lib/spack/spack/test/mirror.py

@@ -11,6 +11,7 @@
 from llnl.util.symlink import resolve_link_target_relative_to_the_link
 
 import spack.caches
+import spack.concretize
 import spack.config
 import spack.fetch_strategy
 import spack.mirrors.layout
@@ -43,7 +44,7 @@ def set_up_package(name, repository, url_attr):
     2. Point the package's version args at that repo.
     """
     # Set up packages to point at mock repos.
-    s = Spec(name).concretized()
+    s = spack.concretize.concretize_one(name)
     repos[name] = repository
 
     # change the fetch args of the first (only) version.
@@ -60,7 +61,7 @@ def check_mirror():
         mirrors = {"spack-mirror-test": url_util.path_to_file_url(mirror_root)}
         with spack.config.override("mirrors", mirrors):
             with spack.config.override("config:checksum", False):
-                specs = [Spec(x).concretized() for x in repos]
+                specs = [spack.concretize.concretize_one(x) for x in repos]
                 spack.mirrors.utils.create(mirror_root, specs)
 
             # Stage directory exists
@@ -77,7 +78,7 @@ def check_mirror():
 
             # Now try to fetch each package.
             for name, mock_repo in repos.items():
-                spec = Spec(name).concretized()
+                spec = spack.concretize.concretize_one(name)
                 pkg = spec.package
 
                 with spack.config.override("config:checksum", False):
@@ -212,13 +213,15 @@ def test_invalid_json_mirror_collection(invalid_json, error_message):
 
 
 def test_mirror_archive_paths_no_version(mock_packages, mock_archive):
-    spec = Spec("trivial-install-test-package@=nonexistingversion").concretized()
+    spec = spack.concretize.concretize_one(
+        Spec("trivial-install-test-package@=nonexistingversion")
+    )
     fetcher = spack.fetch_strategy.URLFetchStrategy(url=mock_archive.url)
     spack.mirrors.layout.default_mirror_layout(fetcher, "per-package-ref", spec)
 
 
 def test_mirror_with_url_patches(mock_packages, monkeypatch):
-    spec = Spec("patch-several-dependencies").concretized()
+    spec = spack.concretize.concretize_one("patch-several-dependencies")
     files_cached_in_mirror = set()
 
     def record_store(_class, fetcher, relative_dst, cosmetic_path=None):