builtin: use api v2.0 and update dir structure (#49275)

* Bump the package API of the `builtin` repo to `v2.0`
* Move `var/spack/repos/builtin` -> `var/spack/repos/spack_repo/builtin`
* Move test repos `var/spack/repos/{builtin.mock,tutorial,...}` -> `var/spack/test_repos/`
* Update package dir names to v2 format (`-` -> `_` etc)
* Change absolute imports `from spack.pkg.builtin.my_pkg ...` to relative imports `from ..my_pkg.package ...`

Users who have a repo on top of builtin should change imports from

```python
from spack.pkg.builtin.my_pkg import MyPkg
```

to

```python
from spack_repo.builtin.packages.my_pkg.package import MyPkg
```

and can configure their editors with

```
PYTHONPATH=$spack/lib/spack:$spack/var/spack/repos
```

[skip-verify-checksums]

.flake8

@@ -28,7 +28,7 @@ max-line-length = 99
 # - F821: undefined name `name`
 #
 per-file-ignores =
-  var/spack/repos/*/package.py:F403,F405,F821
+  var/spack/*/package.py:F403,F405,F821
   *-ci-package.py:F403,F405,F821
 
 # exclude things we usually do not want linting for.

.github/workflows/ci.yaml

@@ -42,17 +42,17 @@ jobs:
           # built-in repository or documentation
           filters: |
             bootstrap:
-            - 'var/spack/repos/builtin/packages/clingo-bootstrap/**'
-            - 'var/spack/repos/builtin/packages/clingo/**'
-            - 'var/spack/repos/builtin/packages/python/**'
-            - 'var/spack/repos/builtin/packages/re2c/**'
-            - 'var/spack/repos/builtin/packages/gnupg/**'
-            - 'var/spack/repos/builtin/packages/libassuan/**'
-            - 'var/spack/repos/builtin/packages/libgcrypt/**'
-            - 'var/spack/repos/builtin/packages/libgpg-error/**'
-            - 'var/spack/repos/builtin/packages/libksba/**'
-            - 'var/spack/repos/builtin/packages/npth/**'
-            - 'var/spack/repos/builtin/packages/pinentry/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/clingo-bootstrap/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/clingo/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/python/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/re2c/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/gnupg/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/libassuan/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/libgcrypt/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/libgpg-error/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/libksba/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/npth/**'
+            - 'var/spack/repos/spack_repo/builtin/packages/pinentry/**'
             - 'lib/spack/**'
             - 'share/spack/**'
             - '.github/workflows/bootstrap.yml'

.github/workflows/prechecks.yml

@@ -34,7 +34,7 @@ jobs:
         vermin --backport importlib --backport argparse --violations --backport typing -t=3.6- -vvv lib/spack/spack/ lib/spack/llnl/ bin/
     - name: vermin (Repositories)
       run: |
-        vermin --backport importlib --backport argparse --violations --backport typing -t=3.6- -vvv var/spack/repos
+        vermin --backport importlib --backport argparse --violations --backport typing -t=3.6- -vvv var/spack/repos var/spack/test_repos
 
   # Run style checks on the files that have been changed
   style:

etc/spack/defaults/repos.yaml

@@ -11,4 +11,4 @@
 #   ~/.spack/repos.yaml
 # -------------------------------------------------------------------------
 repos:
-  - $spack/var/spack/repos/builtin
+  - $spack/var/spack/repos/spack_repo/builtin

lib/spack/docs/basic_usage.rst

@@ -1916,7 +1916,7 @@ diagnostics. Issues, if found, are reported to stdout:
    PKG-DIRECTIVES: 1 issue found
    1. lammps: wrong variant in "conflicts" directive
        the variant 'adios' does not exist
-       in /home/spack/spack/var/spack/repos/builtin/packages/lammps/package.py
+       in /home/spack/spack/var/spack/repos/spack_repo/builtin/packages/lammps/package.py
 
 
 ------------

lib/spack/docs/build_systems.rst

@@ -83,7 +83,7 @@ packages. You can quickly find examples by running:
 
 .. code-block:: console
 
-   $ cd var/spack/repos/builtin/packages
+   $ cd var/spack/repos/spack_repo/builtin/packages
    $ grep -l QMakePackage */package.py
 
 

lib/spack/docs/build_systems/bundlepackage.rst

@@ -27,10 +27,10 @@ it could use the ``require`` directive as follows:
 
 Spack has a number of built-in bundle packages, such as:
 
-* `AmdAocl <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/amd-aocl/package.py>`_
-* `EcpProxyApps <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/ecp-proxy-apps/package.py>`_
-* `Libc <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/libc/package.py>`_
-* `Xsdk <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/xsdk/package.py>`_
+* `AmdAocl <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/amd_aocl/package.py>`_
+* `EcpProxyApps <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/ecp_proxy_apps/package.py>`_
+* `Libc <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/libc/package.py>`_
+* `Xsdk <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/xsdk/package.py>`_
 
 where ``Xsdk`` also inherits from ``CudaPackage`` and ``RocmPackage`` and
 ``Libc`` is a virtual bundle package for the C standard library.

lib/spack/docs/build_systems/cmakepackage.rst

@@ -199,7 +199,7 @@ a variant to control this:
 However, not every CMake package accepts all four of these options.
 Grep the ``CMakeLists.txt`` file to see if the default values are
 missing or replaced. For example, the
-`dealii <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/dealii/package.py>`_
+`dealii <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/dealii/package.py>`_
 package overrides the default variant with:
 
 .. code-block:: python

lib/spack/docs/build_systems/custompackage.rst

@@ -20,8 +20,8 @@ start is to look at the definitions of other build systems. This guide
 focuses mostly on how Spack's build systems work.
 
 In this guide, we will be using the
-`perl <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/perl/package.py>`_ and
-`cmake <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/cmake/package.py>`_
+`perl <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/perl/package.py>`_ and
+`cmake <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/cmake/package.py>`_
 packages as examples. ``perl``'s build system is a hand-written
 ``Configure`` shell script, while ``cmake`` bootstraps itself during
 installation. Both of these packages require custom build systems.

lib/spack/docs/build_systems/makefilepackage.rst

@@ -96,9 +96,9 @@ there are any other variables you need to set, you can do this in the
        env.set("BLASLIB", spec["blas"].libs.ld_flags)
 
 
-`cbench <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/cbench/package.py>`_
+`cbench <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/cbench/package.py>`_
 is a good example of a simple package that does this, while
-`esmf <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/esmf/package.py>`_
+`esmf <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/esmf/package.py>`_
 is a good example of a more complex package.
 
 """"""""""""""""""""""
@@ -129,7 +129,7 @@ If you do need access to the spec, you can create a property like so:
        ]
 
 
-`cloverleaf <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/cloverleaf/package.py>`_
+`cloverleaf <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/cloverleaf/package.py>`_
 is a good example of a package that uses this strategy.
 
 """""""""""""
@@ -152,7 +152,7 @@ and a ``filter`` method to help with this. For example:
        makefile.filter(r"^\s*FC\s*=.*",  f"FC = {spack_fc}")
 
 
-`stream <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/stream/package.py>`_
+`stream <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/stream/package.py>`_
 is a good example of a package that involves editing a Makefile to set
 the appropriate variables.
 
@@ -192,7 +192,7 @@ well for storing variables:
                inc.write(f"{key} = {config[key]}\n")
 
 
-`elk <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/elk/package.py>`_
+`elk <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/elk/package.py>`_
 is a good example of a package that uses a dictionary to store
 configuration variables.
 
@@ -213,7 +213,7 @@ them in a list:
                inc.write(f"{var}\n")
 
 
-`hpl <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/hpl/package.py>`_
+`hpl <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/hpl/package.py>`_
 is a good example of a package that uses a list to store
 configuration variables.
 

lib/spack/docs/build_systems/rpackage.rst

@@ -39,7 +39,7 @@ for "CRAN <package-name>" and you should quickly find what you want.
 If it isn't on CRAN, try Bioconductor, another common R repository.
 
 For the purposes of this tutorial, we will be walking through
-`r-caret <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/r-caret/package.py>`_
+`r-caret <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/r_caret/package.py>`_
 as an example. If you search for "CRAN caret", you will quickly find what
 you are looking for at https://cran.r-project.org/package=caret.
 https://cran.r-project.org is the main CRAN website. However, CRAN also
@@ -337,7 +337,7 @@ Non-R dependencies
 ^^^^^^^^^^^^^^^^^^
 
 Some packages depend on non-R libraries for linking. Check out the
-`r-stringi <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/r-stringi/package.py>`_
+`r-stringi <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/r_stringi/package.py>`_
 package for an example: https://cloud.r-project.org/package=stringi.
 If you search for the text "SystemRequirements", you will see:
 
@@ -352,7 +352,7 @@ Passing arguments to the installation
 
 Some R packages provide additional flags that can be passed to
 ``R CMD INSTALL``, often to locate non-R dependencies.
-`r-rmpi <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/r-rmpi/package.py>`_
+`r-rmpi <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/r_rmpi/package.py>`_
 is an example of this, and flags for linking to an MPI library. To pass
 these to the installation command, you can override ``configure_args``
 like so:

lib/spack/docs/build_systems/sconspackage.rst

@@ -104,10 +104,10 @@ Finding available options
 
 The first place to start when looking for a list of valid options to
 build a package is ``scons --help``. Some packages like
-`kahip <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/kahip/package.py>`_
+`kahip <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/kahip/package.py>`_
 don't bother overwriting the default SCons help message, so this isn't
 very useful, but other packages like
-`serf <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/serf/package.py>`_
+`serf <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/serf/package.py>`_
 print a list of valid command-line variables:
 
 .. code-block:: console
@@ -177,7 +177,7 @@ print a list of valid command-line variables:
 
 
 More advanced packages like
-`cantera <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/cantera/package.py>`_
+`cantera <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/cantera/package.py>`_
 use ``scons --help`` to print a list of subcommands:
 
 .. code-block:: console

lib/spack/docs/contribution_guide.rst

@@ -226,9 +226,9 @@ If all is well, you'll see something like this:
 
    Modified files:
 
-     var/spack/repos/builtin/packages/hdf5/package.py
-     var/spack/repos/builtin/packages/hdf/package.py
-     var/spack/repos/builtin/packages/netcdf/package.py
+     var/spack/repos/spack_repo/builtin/packages/hdf5/package.py
+     var/spack/repos/spack_repo/builtin/packages/hdf/package.py
+     var/spack/repos/spack_repo/builtin/packages/netcdf/package.py
    =======================================================
    Flake8 checks were clean.
 
@@ -236,9 +236,9 @@ However, if you aren't compliant with PEP 8, flake8 will complain:
 
 .. code-block:: console
 
-   var/spack/repos/builtin/packages/netcdf/package.py:26: [F401] 'os' imported but unused
-   var/spack/repos/builtin/packages/netcdf/package.py:61: [E303] too many blank lines (2)
-   var/spack/repos/builtin/packages/netcdf/package.py:106: [E501] line too long (92 > 79 characters)
+   var/spack/repos/spack_repo/builtin/packages/netcdf/package.py:26: [F401] 'os' imported but unused
+   var/spack/repos/spack_repo/builtin/packages/netcdf/package.py:61: [E303] too many blank lines (2)
+   var/spack/repos/spack_repo/builtin/packages/netcdf/package.py:106: [E501] line too long (92 > 79 characters)
    Flake8 found errors.
 
 Most of the error messages are straightforward, but if you don't understand what
@@ -280,7 +280,7 @@ All of these can be installed with Spack, e.g.
 
 .. warning::
 
-   Sphinx has `several required dependencies <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/py-sphinx/package.py>`_.
+   Sphinx has `several required dependencies <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/py-sphinx/package.py>`_.
    If you're using a ``python`` from Spack and you installed
    ``py-sphinx`` and friends, you need to make them available to your
    ``python``. The easiest way to do this is to run:

lib/spack/docs/features.rst

@@ -131,7 +131,7 @@ creates a simple python file:
 It doesn't take much python coding to get from there to a working
 package:
 
-.. literalinclude:: _spack_root/var/spack/repos/builtin/packages/libelf/package.py
+.. literalinclude:: _spack_root/var/spack/repos/spack_repo/builtin/packages/libelf/package.py
    :lines: 5-
 
 Spack also provides wrapper functions around common commands like

lib/spack/docs/packaging_guide.rst

@@ -369,9 +369,9 @@ If you have a collection of software expected to work well together with
 no source code of its own, you can create a :ref:`BundlePackage <bundlepackage>`.
 Examples where bundle packages can be useful include defining suites of
 applications (e.g, `EcpProxyApps
-<https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/ecp-proxy-apps/package.py>`_), commonly used libraries
-(e.g., `AmdAocl <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/amd-aocl/package.py>`_),
-and software development kits (e.g., `EcpDataVisSdk <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/ecp-data-vis-sdk/package.py>`_).
+<https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/ecp_proxy_apps/package.py>`_), commonly used libraries
+(e.g., `AmdAocl <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/amd_aocl/package.py>`_),
+and software development kits (e.g., `EcpDataVisSdk <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/ecp_data_vis_sdk/package.py>`_).
 
 These versioned packages primarily consist of dependencies on the associated
 software packages. They can include :ref:`variants <variants>` to ensure
@@ -443,7 +443,7 @@ lives in:
 .. code-block:: console
 
    $ spack location -p gmp
-   ${SPACK_ROOT}/var/spack/repos/builtin/packages/gmp/package.py
+   ${SPACK_ROOT}/var/spack/repos/spack_repo/builtin/packages/gmp/package.py
 
 but ``spack edit`` provides a much simpler shortcut and saves you the
 trouble of typing the full path.
@@ -457,19 +457,19 @@ live in Spack's directory structure.  In general, :ref:`cmd-spack-create`
 handles creating package files for you, so you can skip most of the
 details here.
 
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-``var/spack/repos/builtin/packages``
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+``var/spack/repos/spack_repo/builtin/packages``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 A Spack installation directory is structured like a standard UNIX
 install prefix (``bin``, ``lib``, ``include``, ``var``, ``opt``,
 etc.).  Most of the code for Spack lives in ``$SPACK_ROOT/lib/spack``.
-Packages themselves live in ``$SPACK_ROOT/var/spack/repos/builtin/packages``.
+Packages themselves live in ``$SPACK_ROOT/var/spack/repos/spack_repo/builtin/packages``.
 
 If you ``cd`` to that directory, you will see directories for each
 package:
 
-.. command-output:: cd $SPACK_ROOT/var/spack/repos/builtin/packages && ls
+.. command-output:: cd $SPACK_ROOT/var/spack/repos/spack_repo/builtin/packages && ls
    :shell:
    :ellipsis: 10
 
@@ -479,7 +479,7 @@ package lives in:
 
 .. code-block:: none
 
-   $SPACK_ROOT/var/spack/repos/builtin/packages/libelf/package.py
+   $SPACK_ROOT/var/spack/repos/spack_repo/builtin/packages/libelf/package.py
 
 Alongside the ``package.py`` file, a package may contain extra
 directories or files (like patches) that it needs to build.
@@ -492,7 +492,7 @@ Packages are named after the directory containing ``package.py``. So,
 ``libelf``'s ``package.py`` lives in a directory called ``libelf``.
 The ``package.py`` file defines a class called ``Libelf``, which
 extends Spack's ``Package`` class.  For example, here is
-``$SPACK_ROOT/var/spack/repos/builtin/packages/libelf/package.py``:
+``$SPACK_ROOT/var/spack/repos/spack_repo/builtin/packages/libelf/package.py``:
 
 .. code-block:: python
    :linenos:
@@ -520,7 +520,7 @@ these:
    $ spack install libelf@0.8.13
 
 Spack sees the package name in the spec and looks for
-``libelf/package.py`` in ``var/spack/repos/builtin/packages``.
+``libelf/package.py`` in ``var/spack/repos/spack_repo/builtin/packages``.
 Likewise, if you run ``spack install py-numpy``, Spack looks for
 ``py-numpy/package.py``.
 
@@ -686,7 +686,7 @@ https://www.open-mpi.org/software/ompi/v2.1/downloads/openmpi-2.1.1.tar.bz2
 In order to handle this, you can define a ``url_for_version()`` function
 like so:
 
-.. literalinclude:: _spack_root/var/spack/repos/builtin/packages/openmpi/package.py
+.. literalinclude:: _spack_root/var/spack/repos/spack_repo/builtin/packages/openmpi/package.py
    :pyobject: Openmpi.url_for_version
 
 With the use of this ``url_for_version()``, Spack knows to download OpenMPI ``2.1.1``
@@ -787,7 +787,7 @@ of GNU. For that, Spack goes a step further and defines a mixin class that
 takes care of all of the plumbing and requires packagers to just define a proper
 ``gnu_mirror_path`` attribute:
 
-.. literalinclude:: _spack_root/var/spack/repos/builtin/packages/autoconf/package.py
+.. literalinclude:: _spack_root/var/spack/repos/spack_repo/builtin/packages/autoconf/package.py
    :lines: 9-18
 
 ^^^^^^^^^^^^^^^^^^^^^^^^
@@ -1995,7 +1995,7 @@ structure like this:
 
 .. code-block:: none
 
-   $SPACK_ROOT/var/spack/repos/builtin/packages/
+   $SPACK_ROOT/var/spack/repos/spack_repo/builtin/packages/
        mvapich2/
            package.py
            ad_lustre_rwcontig_open_source.patch
@@ -2133,7 +2133,7 @@ handles ``RPATH``:
 
 .. _pyside-patch:
 
-.. literalinclude:: _spack_root/var/spack/repos/builtin/packages/py-pyside/package.py
+.. literalinclude:: _spack_root/var/spack/repos/spack_repo/builtin/packages/py_pyside/package.py
    :pyobject: PyPyside.patch
    :linenos:
 
@@ -2201,7 +2201,7 @@ using the ``spack resource show`` command::
 
   $ spack resource show 3877ab54
   3877ab548f88597ab2327a2230ee048d2d07ace1062efe81fc92e91b7f39cd00
-      path:       /home/spackuser/src/spack/var/spack/repos/builtin/packages/m4/gnulib-pgi.patch
+      path:       /home/spackuser/src/spack/var/spack/repos/spack_repo/builtin/packages/m4/gnulib-pgi.patch
       applies to: builtin.m4
 
 ``spack resource show`` looks up downloadable resources from package
@@ -2219,7 +2219,7 @@ wonder where the extra boost patches are coming from::
           ^boost@1.68.0%apple-clang@9.0.0+atomic+chrono~clanglibcpp cxxstd=default +date_time~debug+exception+filesystem+graph~icu+iostreams+locale+log+math~mpi+multithreaded~numpy patches=2ab6c72d03dec6a4ae20220a9dfd5c8c572c5294252155b85c6874d97c323199,b37164268f34f7133cbc9a4066ae98fda08adf51e1172223f6a969909216870f ~pic+program_options~python+random+regex+serialization+shared+signals~singlethreaded+system~taggedlayout+test+thread+timer~versionedlayout+wave arch=darwin-highsierra-x86_64
   $ spack resource show b37164268
   b37164268f34f7133cbc9a4066ae98fda08adf51e1172223f6a969909216870f
-      path:       /home/spackuser/src/spack/var/spack/repos/builtin/packages/dealii/boost_1.68.0.patch
+      path:       /home/spackuser/src/spack/var/spack/repos/spack_repo/builtin/packages/dealii/boost_1.68.0.patch
       applies to: builtin.boost
       patched by: builtin.dealii
 
@@ -2930,7 +2930,7 @@ this, Spack provides four different methods that can be overridden in a package:
 
 The Qt package, for instance, uses this call:
 
-.. literalinclude:: _spack_root/var/spack/repos/builtin/packages/qt/package.py
+.. literalinclude:: _spack_root/var/spack/repos/spack_repo/builtin/packages/qt/package.py
    :pyobject: Qt.setup_dependent_build_environment
    :linenos:
 
@@ -2958,7 +2958,7 @@ variables to be used by the dependent. This is done by implementing
 :meth:`setup_dependent_package <spack.package_base.PackageBase.setup_dependent_package>`. An
 example of this can be found in the ``Python`` package:
 
-.. literalinclude:: _spack_root/var/spack/repos/builtin/packages/python/package.py
+.. literalinclude:: _spack_root/var/spack/repos/spack_repo/builtin/packages/python/package.py
    :pyobject: Python.setup_dependent_package
    :linenos:
 
@@ -3785,7 +3785,7 @@ It is usually sufficient for a packager to override a few
 build system specific helper methods or attributes to provide, for instance,
 configure arguments:
 
-.. literalinclude::  _spack_root/var/spack/repos/builtin/packages/m4/package.py
+.. literalinclude::  _spack_root/var/spack/repos/spack_repo/builtin/packages/m4/package.py
     :pyobject: M4.configure_args
     :linenos:
 
@@ -4110,7 +4110,7 @@ Shell command functions
 
 Recall the install method from ``libelf``:
 
-.. literalinclude::  _spack_root/var/spack/repos/builtin/packages/libelf/package.py
+.. literalinclude::  _spack_root/var/spack/repos/spack_repo/builtin/packages/libelf/package.py
    :pyobject: Libelf.install
    :linenos:
 
@@ -4901,7 +4901,7 @@ the one passed to install, only the MPI implementations all set some
 additional properties on it to help you out.  E.g., in openmpi, you'll
 find this:
 
-.. literalinclude:: _spack_root/var/spack/repos/builtin/packages/openmpi/package.py
+.. literalinclude:: _spack_root/var/spack/repos/spack_repo/builtin/packages/openmpi/package.py
    :pyobject: Openmpi.setup_dependent_package
 
 That code allows the ``openmpi`` package to associate an ``mpicc`` property
@@ -6001,16 +6001,16 @@ with those implemented in the package itself.
    * - Parent/Provider Package
      - Stand-alone Tests
    * - `C
-       <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/c>`_
+       <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/c>`_
      - Compiles ``hello.c`` and runs it
    * - `Cxx
-       <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/cxx>`_
+       <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/cxx>`_
      - Compiles and runs several ``hello`` programs
    * - `Fortran
-       <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/fortran>`_
+       <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/fortran>`_
      - Compiles and runs ``hello`` programs (``F`` and ``f90``)
    * - `Mpi
-       <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/mpi>`_
+       <https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/mpi>`_
      - Compiles and runs ``mpi_hello`` (``c``, ``fortran``)
    * - :ref:`PythonPackage <pythonpackage>`
      - Imports modules listed in the ``self.import_modules`` property with defaults derived from the tarball
@@ -6031,7 +6031,7 @@ maintainers provide additional stand-alone tests customized to the package.
 One example of a package that adds its own stand-alone tests to those
 "inherited" by the virtual package it provides an implementation for is
 the `Openmpi package
-<https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/openmpi/package.py>`_.
+<https://github.com/spack/spack/blob/develop/var/spack/repos/spack_repo/builtin/packages/openmpi/package.py>`_.
 
 Below are snippets from running and viewing the stand-alone test results
 for ``openmpi``:

lib/spack/docs/repositories.rst

@@ -9,7 +9,7 @@ Package Repositories (repos.yaml)
 =================================
 
 Spack comes with thousands of built-in package recipes in
-``var/spack/repos/builtin/``.  This is a **package repository** -- a
+``var/spack/repos/spack_repo/builtin/``.  This is a **package repository** -- a
 directory that Spack searches when it needs to find a package by name.
 You may need to maintain packages for restricted, proprietary or
 experimental software separately from the built-in repository. Spack
@@ -69,7 +69,7 @@ The default ``etc/spack/defaults/repos.yaml`` file looks like this:
 .. code-block:: yaml
 
   repos:
-  - $spack/var/spack/repos/builtin
+  - $spack/var/spack/repos/spack_repo/builtin
 
 The file starts with ``repos:`` and contains a single ordered list of
 paths to repositories. Each path is on a separate line starting with
@@ -78,16 +78,16 @@ paths to repositories. Each path is on a separate line starting with
 .. code-block:: yaml
 
   repos:
-  - /opt/local-repo
-  - $spack/var/spack/repos/builtin
+  - /opt/repos/spack_repo/local_repo
+  - $spack/var/spack/repos/spack_repo/builtin
 
 When Spack interprets a spec, e.g., ``mpich`` in ``spack install mpich``,
 it searches these repositories in order (first to last) to resolve each
 package name.  In this example, Spack will look for the following
 packages and use the first valid file:
 
-1. ``/opt/local-repo/packages/mpich/package.py``
-2. ``$spack/var/spack/repos/builtin/packages/mpich/package.py``
+1. ``/opt/repos/spack_repo/local_repo/packages/mpich/package.py``
+2. ``$spack/var/spack/repos/spack_repo/builtin/packages/mpich/package.py``
 
 .. note::
 
@@ -101,14 +101,15 @@ Namespaces
 
 Every repository in Spack has an associated **namespace** defined in its
 top-level ``repo.yaml`` file.  If you look at
-``var/spack/repos/builtin/repo.yaml`` in the built-in repository, you'll
+``var/spack/repos/spack_repo/builtin/repo.yaml`` in the built-in repository, you'll
 see that its namespace is ``builtin``:
 
 .. code-block:: console
 
-  $ cat var/spack/repos/builtin/repo.yaml
+  $ cat var/spack/repos/spack_repo/builtin/repo.yaml
   repo:
     namespace: builtin
+    api: v2.0
 
 Spack records the repository namespace of each installed package.  For
 example, if you install the ``mpich`` package from the ``builtin`` repo,
@@ -217,15 +218,15 @@ Suppose you have three repositories: the builtin Spack repo
 repo containing your own prototype packages (``proto``).  Suppose they
 contain packages as follows:
 
-  +--------------+------------------------------------+-----------------------------+
-  | Namespace    | Path to repo                       | Packages                    |
-  +==============+====================================+=============================+
-  | ``proto``    | ``~/proto``                        | ``mpich``                   |
-  +--------------+------------------------------------+-----------------------------+
-  | ``llnl``     | ``/usr/local/llnl``                | ``hdf5``                    |
-  +--------------+------------------------------------+-----------------------------+
-  | ``builtin``  | ``$spack/var/spack/repos/builtin`` | ``mpich``, ``hdf5``, others |
-  +--------------+------------------------------------+-----------------------------+
+  +--------------+-----------------------------------------------+-----------------------------+
+  | Namespace    | Path to repo                                  | Packages                    |
+  +==============+===============================================+=============================+
+  | ``proto``    | ``~/my_spack_repos/spack_repo/proto``         | ``mpich``                   |
+  +--------------+-----------------------------------------------+-----------------------------+
+  | ``llnl``     | ``/usr/local/repos/spack_repo/llnl``          | ``hdf5``                    |
+  +--------------+-----------------------------------------------+-----------------------------+
+  | ``builtin``  | ``$spack/var/spack/repos/spack_repo/builtin`` | ``mpich``, ``hdf5``, others |
+  +--------------+-----------------------------------------------+-----------------------------+
 
 Suppose that ``hdf5`` depends on ``mpich``.  You can override the
 built-in ``hdf5`` by adding the ``llnl`` repo to ``repos.yaml``:
@@ -233,8 +234,8 @@ built-in ``hdf5`` by adding the ``llnl`` repo to ``repos.yaml``:
 .. code-block:: yaml
 
    repos:
-   - /usr/local/llnl
-   - $spack/var/spack/repos/builtin
+   - /usr/local/repos/spack_repo/llnl
+   - $spack/var/spack/repos/spack_repo/builtin
 
 ``spack install hdf5`` will install ``llnl.hdf5 ^builtin.mpich``.
 
@@ -243,9 +244,9 @@ If, instead, ``repos.yaml`` looks like this:
 .. code-block:: yaml
 
    repos:
-   - ~/proto
-   - /usr/local/llnl
-   - $spack/var/spack/repos/builtin
+   - ~/my_spack_repos/spack_repo/proto
+   - /usr/local/repos/spack_repo/llnl
+   - $spack/var/spack/repos/spack_repo/builtin
 
 ``spack install hdf5`` will install ``llnl.hdf5 ^proto.mpich``.
 
@@ -326,8 +327,8 @@ files, use ``spack repo list``.
 
   $ spack repo list
   ==> 2 package repositories.
-  myrepo     ~/myrepo
-  builtin    ~/spack/var/spack/repos/builtin
+  myrepo     v2.0    ~/my_spack_repos/spack_repo/myrepo
+  builtin    v2.0    ~/spack/var/spack/repos/spack_repo/builtin
 
 Each repository is listed with its associated namespace.  To get the raw,
 merged YAML from all configuration files, use ``spack config get repos``:
@@ -335,9 +336,9 @@ merged YAML from all configuration files, use ``spack config get repos``:
 .. code-block:: console
 
    $ spack config get repos
-   repos:srepos:
-   - ~/myrepo
-   - $spack/var/spack/repos/builtin
+   repos:
+   - ~/my_spack_repos/spack_repo/myrepo
+   - $spack/var/spack/repos/spack_repo/builtin
 
 Note that, unlike ``spack repo list``, this does not include the
 namespace, which is read from each repo's ``repo.yaml``.
@@ -351,66 +352,54 @@ yourself; you can use the ``spack repo create`` command.
 
 .. code-block:: console
 
-  $ spack repo create myrepo
+  $ spack repo create ~/my_spack_repos myrepo
   ==> Created repo with namespace 'myrepo'.
   ==> To register it with spack, run this command:
-    spack repo add ~/myrepo
+    spack repo add ~/my_spack_repos/spack_repo/myrepo
 
-  $ ls myrepo
+  $ ls ~/my_spack_repos/spack_repo/myrepo
   packages/  repo.yaml
 
-  $ cat myrepo/repo.yaml
+  $ cat ~/my_spack_repos/spack_repo/myrepo/repo.yaml
   repo:
     namespace: 'myrepo'
+    api: v2.0
 
-By default, the namespace of a new repo matches its directory's name.
-You can supply a custom namespace with a second argument, e.g.:
+Namespaces can also be nested, which can be useful if you have
+multiple package repositories for an organization. Spack will
+create the corresponding directory structure for you:
 
 .. code-block:: console
 
-  $ spack repo create myrepo llnl.comp
+  $ spack repo create ~/my_spack_repos llnl.comp
   ==> Created repo with namespace 'llnl.comp'.
   ==> To register it with spack, run this command:
-    spack repo add ~/myrepo
+    spack repo add ~/my_spack_repos/spack_repo/llnl/comp
 
-  $ cat myrepo/repo.yaml
+
+  $ cat ~/my_spack_repos/spack_repo/llnl/comp/repo.yaml
   repo:
     namespace: 'llnl.comp'
-
-You can also create repositories with custom structure with the ``-d/--subdirectory``
-argument, e.g.:
-
-.. code-block:: console
-
-  $ spack repo create -d applications myrepo apps
-  ==> Created repo with namespace 'apps'.
-  ==> To register it with Spack, run this command:
-    spack repo add ~/myrepo
-
-  $ ls myrepo
-  applications/  repo.yaml
-
-  $ cat myrepo/repo.yaml
-  repo:
-    namespace: apps
-    subdirectory: applications
+    api: v2.0
 
 ^^^^^^^^^^^^^^^^^^
 ``spack repo add``
 ^^^^^^^^^^^^^^^^^^
 
 Once your repository is created, you can register it with Spack with
-``spack repo add``:
+``spack repo add``. You nee to specify the path to the directory that
+contains the ``repo.yaml`` file.
 
 .. code-block:: console
 
-   $ spack repo add ./myrepo
+   $ spack repo add ~/my_spack_repos/spack_repo/llnl/comp
    ==> Added repo with namespace 'llnl.comp'.
 
    $ spack repo list
    ==> 2 package repositories.
-   llnl.comp    ~/myrepo
-   builtin      ~/spack/var/spack/repos/builtin
+  llnl.comp    v2.0    ~/my_spack_repos/spack_repo/llnl/comp
+  builtin      v2.0    ~/spack/var/spack/repos/spack_repo/builtin
+
 
 This simply adds the repo to your ``repos.yaml`` file.
 
@@ -432,46 +421,43 @@ By namespace:
 .. code-block:: console
 
   $ spack repo rm llnl.comp
-  ==> Removed repository ~/myrepo with namespace 'llnl.comp'.
+  ==> Removed repository ~/my_spack_repos/spack_repo/llnl/comp with namespace 'llnl.comp'.
 
   $ spack repo list
   ==> 1 package repository.
-  builtin    ~/spack/var/spack/repos/builtin
+  builtin    ~/spack/var/spack/repos/spack_repo/builtin
 
 By path:
 
 .. code-block:: console
 
-  $ spack repo rm ~/myrepo
-  ==> Removed repository ~/myrepo
+  $ spack repo rm ~/my_spack_repos/spack_repo/llnl/comp
+  ==> Removed repository ~/my_spack_repos/spack_repo/llnl/comp
 
   $ spack repo list
   ==> 1 package repository.
-  builtin    ~/spack/var/spack/repos/builtin
+  builtin    ~/spack/var/spack/repos/spack_repo/builtin
 
 --------------------------------
 Repo namespaces and Python
 --------------------------------
 
-You may have noticed that namespace notation for repositories is similar
-to the notation for namespaces in Python.  As it turns out, you *can*
-treat Spack repositories like Python packages; this is how they are
-implemented.
+Package repositories are implemented as Python packages. To be precise,
+they are `namespace packages
+<https://packaging.python.org/en/latest/guides/packaging-namespace-packages/>`_
+with ``spack_repo`` the top-level namespace, followed by the repository
+namespace as submodules. For example, the builtin repository corresponds
+to the Python module ``spack_repo.builtin.packages``.
 
-You could, for example, extend a ``builtin`` package in your own
+This structure allows you to extend a ``builtin`` package in your own
 repository:
 
 .. code-block:: python
 
-   from spack.pkg.builtin.mpich import Mpich
+   from spack_repo.builtin.packages.mpich.package import Mpich
 
    class MyPackage(Mpich):
        ...
 
-Spack repo namespaces are actually Python namespaces tacked on under
-``spack.pkg``.  The search semantics of ``repos.yaml`` are actually
-implemented using Python's built-in `sys.path
-<https://docs.python.org/2/library/sys.html#sys.path>`_ search.  The
-:py:mod:`spack.repo` module implements a custom `Python importer
-<https://docs.python.org/2/library/imp.html>`_.
-
+Spack populates ``sys.path`` at runtime with the path to the root of your
+package repository's ``spack_repo`` directory.

lib/spack/spack/build_systems/intel.py

@@ -1055,8 +1055,8 @@ def setup_dependent_build_environment(
     ) -> None:
         # NB: This function is overwritten by 'mpi' provider packages:
         #
-        # var/spack/repos/builtin/packages/intel-mpi/package.py
-        # var/spack/repos/builtin/packages/intel-parallel-studio/package.py
+        # var/spack/repos/spack_repo/builtin/packages/intel_mpi/package.py
+        # var/spack/repos/spack_repo/builtin/packages/intel_parallel_studio/package.py
         #
         # They call _setup_dependent_env_callback() as well, but with the
         # dictionary kwarg compilers_of_client{} present and populated.

lib/spack/spack/cmd/list.py

@@ -10,11 +10,13 @@
 import re
 import sys
 from html import escape
+from typing import Type
 
 import llnl.util.tty as tty
 from llnl.util.tty.colify import colify
 
 import spack.deptypes as dt
+import spack.package_base
 import spack.repo
 from spack.cmd.common import arguments
 from spack.version import VersionList
@@ -139,10 +141,10 @@ def name_only(pkgs, out):
         tty.msg("%d packages" % len(pkgs))
 
 
-def github_url(pkg):
+def github_url(pkg: Type[spack.package_base.PackageBase]) -> str:
     """Link to a package file on github."""
-    url = "https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/{0}/package.py"
-    return url.format(pkg.name)
+    mod_path = pkg.__module__.replace(".", "/")
+    return f"https://github.com/spack/spack/blob/develop/var/spack/{mod_path}.py"
 
 
 def rows_for_ncols(elts, ncols):

lib/spack/spack/cmd/style.py

@@ -59,7 +59,7 @@ def is_package(f):
     packages, since we allow `from spack import *` and poking globals
     into packages.
     """
-    return f.startswith("var/spack/repos/") and f.endswith("package.py")
+    return f.startswith("var/spack/") and f.endswith("package.py")
 
 
 #: decorator for adding tools to the list

lib/spack/spack/paths.py

@@ -56,8 +56,9 @@
 
 # read-only things in $spack/var/spack
 repos_path = os.path.join(var_path, "repos")
-packages_path = os.path.join(repos_path, "builtin")
-mock_packages_path = os.path.join(repos_path, "builtin.mock")
+test_repos_path = os.path.join(var_path, "test_repos")
+packages_path = os.path.join(repos_path, "spack_repo", "builtin")
+mock_packages_path = os.path.join(test_repos_path, "builtin.mock")
 
 #
 # Writable things in $spack/var/spack

lib/spack/spack/test/builder.py

@@ -15,7 +15,7 @@
 
 @pytest.fixture()
 def builder_test_repository(config):
-    builder_test_path = os.path.join(spack.paths.repos_path, "builder.test")
+    builder_test_path = os.path.join(spack.paths.test_repos_path, "builder.test")
     with spack.repo.use_repositories(builder_test_path) as mock_repo:
         yield mock_repo
 

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

@@ -143,8 +143,8 @@ def test_list_count():
 
 def test_list_repos():
     with spack.repo.use_repositories(
-        os.path.join(spack.paths.repos_path, "builtin.mock"),
-        os.path.join(spack.paths.repos_path, "builder.test"),
+        os.path.join(spack.paths.test_repos_path, "builtin.mock"),
+        os.path.join(spack.paths.test_repos_path, "builder.test"),
     ):
         total_pkgs = len(list().strip().split())
         mock_pkgs = len(list("-r", "builtin.mock").strip().split())

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

@@ -159,8 +159,12 @@ def test_bad_root(tmpdir):
 
 def test_style_is_package(tmpdir):
     """Ensure the is_package() function works."""
-    assert spack.cmd.style.is_package("var/spack/repos/builtin/packages/hdf5/package.py")
-    assert spack.cmd.style.is_package("var/spack/repos/builtin/packages/zlib/package.py")
+    assert spack.cmd.style.is_package(
+        "var/spack/repos/spack_repo/builtin/packages/hdf5/package.py"
+    )
+    assert spack.cmd.style.is_package(
+        "var/spack/repos/spack_repo/builtin/packages/zlib/package.py"
+    )
     assert not spack.cmd.style.is_package("lib/spack/spack/spec.py")
     assert not spack.cmd.style.is_package("lib/spack/external/pytest.py")
 

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

@@ -29,7 +29,7 @@ def _concretize_with_reuse(*, root_str, reused_str):
 
 @pytest.fixture
 def runtime_repo(mutable_config):
-    repo = os.path.join(spack.paths.repos_path, "compiler_runtime.test")
+    repo = os.path.join(spack.paths.test_repos_path, "compiler_runtime.test")
     with spack.repo.use_repositories(repo) as mock_repo:
         yield mock_repo
 

lib/spack/spack/test/concretization/core.py

@@ -2332,7 +2332,7 @@ def test_select_lower_priority_package_from_repository_stack(
         from cli.
         """
         # 'builtin.mock" and "duplicates.test" share a 'gmake' package
-        additional_repo = os.path.join(spack.paths.repos_path, "duplicates.test")
+        additional_repo = os.path.join(spack.paths.test_repos_path, "duplicates.test")
         with spack.repo.use_repositories(additional_repo, override=False):
             s = spack.concretize.concretize_one(spec_str)
 
@@ -2576,7 +2576,7 @@ def test_correct_external_is_selected_from_packages_yaml(self, mutable_config):
 
 @pytest.fixture()
 def duplicates_test_repository():
-    repository_path = os.path.join(spack.paths.repos_path, "duplicates.test")
+    repository_path = os.path.join(spack.paths.test_repos_path, "duplicates.test")
     with spack.repo.use_repositories(repository_path) as mock_repo:
         yield mock_repo
 
@@ -2811,7 +2811,7 @@ def test_adding_specs(self, input_specs, default_mock_concretization):
 
 @pytest.fixture()
 def edges_test_repository():
-    repository_path = os.path.join(spack.paths.repos_path, "edges.test")
+    repository_path = os.path.join(spack.paths.test_repos_path, "edges.test")
     with spack.repo.use_repositories(repository_path) as mock_repo:
         yield mock_repo
 

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

@@ -46,7 +46,7 @@
 
 @pytest.fixture
 def test_repo(mutable_config, monkeypatch, mock_stage):
-    repo_dir = pathlib.Path(spack.paths.repos_path) / "flags.test"
+    repo_dir = pathlib.Path(spack.paths.test_repos_path) / "flags.test"
     with spack.repo.use_repositories(str(repo_dir)) as mock_repo_path:
         yield mock_repo_path
 

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

@@ -28,7 +28,7 @@ def update_packages_config(conf_str):
 
 @pytest.fixture
 def test_repo(mutable_config, monkeypatch, mock_stage):
-    repo_dir = pathlib.Path(spack.paths.repos_path) / "requirements.test"
+    repo_dir = pathlib.Path(spack.paths.test_repos_path) / "requirements.test"
     with spack.repo.use_repositories(str(repo_dir)) as mock_repo_path:
         yield mock_repo_path
 

lib/spack/spack/test/config.py

@@ -914,7 +914,7 @@ def test_single_file_scope(config, env_yaml):
         assert spack.config.get("config:checksum") is True
         assert spack.config.get("config:checksum") is True
         assert spack.config.get("packages:externalmodule:buildable") is False
-        assert spack.config.get("repos") == ["/x/y/z", "$spack/var/spack/repos/builtin"]
+        assert spack.config.get("repos") == ["/x/y/z", "$spack/var/spack/repos/spack_repo/builtin"]
 
 
 def test_single_file_scope_section_override(tmpdir, config):
@@ -950,7 +950,7 @@ def test_single_file_scope_section_override(tmpdir, config):
         # from the lower config scopes
         assert spack.config.get("config:checksum") is True
         assert not spack.config.get("packages:externalmodule")
-        assert spack.config.get("repos") == ["/x/y/z", "$spack/var/spack/repos/builtin"]
+        assert spack.config.get("repos") == ["/x/y/z", "$spack/var/spack/repos/spack_repo/builtin"]
 
 
 def test_write_empty_single_file_scope(tmpdir):

lib/spack/spack/test/data/config/repos.yaml

@@ -1,2 +1,2 @@
 repos:
-  - $spack/var/spack/repos/builtin
+  - $spack/var/spack/repos/spack_repo/builtin

lib/spack/spack/test/repo.py

@@ -219,7 +219,7 @@ def test_use_repositories_and_import():
     """Tests that use_repositories changes the import search too"""
     import spack.paths
 
-    repo_dir = pathlib.Path(spack.paths.repos_path)
+    repo_dir = pathlib.Path(spack.paths.test_repos_path)
     with spack.repo.use_repositories(str(repo_dir / "compiler_runtime.test")):
         import spack.pkg.compiler_runtime.test.gcc_runtime
 

pyproject.toml

@@ -99,12 +99,12 @@ archspec = ["archspec"]
 llnl = ["llnl"]
 
 [tool.ruff.lint.per-file-ignores]
-"var/spack/repos/*/package.py" = ["F403", "F405", "F811", "F821"]
+"var/spack/*/package.py" = ["F403", "F405", "F811", "F821"]
 "*-ci-package.py" = ["F403", "F405", "F821"]
 
 [tool.black]
 line-length = 99
-include = '(lib/spack|var/spack/repos)/.*\.pyi?$|bin/spack$'
+include = '(lib/spack|var/spack/repos|var/spack/test_repos)/.*\.pyi?$|bin/spack$'
 extend-exclude = 'lib/spack/external'
 skip_magic_trailing_comma = true
 
@@ -126,8 +126,16 @@ src_paths = "lib"
 honor_noqa = true
 
 [tool.mypy]
-files = ['lib/spack/llnl/**/*.py', 'lib/spack/spack/**/*.py', './var/spack/repos/builtin/packages/*/package.py']
-mypy_path = ['bin', 'lib/spack', 'lib/spack/external', 'var/spack/repos/builtin']
+files = [
+  "lib/spack/llnl/**/*.py",
+  "lib/spack/spack/**/*.py",
+  "var/spack/repos/spack_repo/builtin/packages/*/package.py"
+]
+mypy_path = [
+  "lib/spack",
+  "lib/spack/external",
+  "var/spack/repos",
+]
 allow_redefinition = true
 
 # This and a generated import file allows supporting packages
@@ -144,7 +152,7 @@ ignore_missing_imports = true
   ignore_missing_imports = false
 
   [[tool.mypy.overrides]]
-  module = 'packages.*'
+  module = 'spack_repo.*'
   ignore_errors = false
   ignore_missing_imports = false
   # we can't do this here, not a module scope option, in spack style instead
@@ -197,7 +205,7 @@ ignore_missing_imports = true
 useLibraryCodeForTypes = true
 reportMissingImports = true
 reportWildcardImportFromLibrary = false
-include = ['lib/spack', 'var/spack/repos']
+include = ['lib/spack', 'var/spack/repos', 'var/spack/test_repos']
 ignore = ['lib/spack/external']
 extraPaths = ['lib/spack', 'lib/spack/external']
 

share/spack/qa/run-unit-tests

@@ -40,7 +40,9 @@ spack -p --lines 20 spec mpileaks%gcc
 $coverage_run $(which spack) bootstrap status --dev --optional
 
 # Check that we can import Spack packages directly as a first import
-$coverage_run $(which spack) python -c "import spack.pkg.builtin.mpileaks; repr(spack.pkg.builtin.mpileaks.Mpileaks)"
+# TODO: this check is disabled, because sys.path is only updated once
+# spack.repo.PATH.get_pkg_class is called.
+# $coverage_run $(which spack) python -c "import spack.pkg.builtin.mpileaks; repr(spack.pkg.builtin.mpileaks.Mpileaks)"
 
 #-----------------------------------------------------------
 # Run unit tests with code coverage

var/spack/repos/builtin.mock/packages/compiler-wrapper

@@ -1 +0,0 @@
-../../builtin/packages/compiler-wrapper/

var/spack/repos/builtin.mock/packages/gcc-runtime

@@ -1 +0,0 @@
-../../builtin/packages/gcc-runtime

var/spack/repos/compiler_runtime.test/packages/compiler-wrapper

@@ -1 +0,0 @@
-../../builtin/packages/compiler-wrapper/

var/spack/repos/flags.test/packages/compiler-wrapper

@@ -1 +0,0 @@
-../../builtin/packages/compiler-wrapper/

var/spack/repos/spack_repo/builtin/packages/abyss/package.py

@@ -5,7 +5,8 @@
 import numbers
 
 from spack.package import *
-from spack.pkg.builtin.boost import Boost
+
+from ..boost.package import Boost
 
 
 def is_multiple_32(x):

var/spack/repos/spack_repo/builtin/packages/additivefoam/package.py

@@ -5,9 +5,10 @@
 import inspect
 import os
 
-import spack.pkg.builtin.openfoam as openfoam
 from spack.package import *
 
+from ..openfoam import package as openfoam
+
 
 class Additivefoam(Package):
     """AdditiveFOAM is a heat and mass transfer software for Additive Manufacturing (AM)"""
@@ -39,7 +40,7 @@ class Additivefoam(Package):
     def add_extra_files(self, common, local_prefix, local):
         """Copy additional common and local files into the stage.source_path
         from the openfoam/common and the package/assets directories,
-        respectively. Modified from `spack.pkg.builtin.openfoam.add_extra_files()`.
+        respectively. Modified from `..openfoam.package.OpenFoam.add_extra_files()`.
         """
         outdir = self.stage.source_path
         indir = join_path(os.path.dirname(inspect.getfile(openfoam)), "common")