diff --git a/lib/spack/spack/paths.py b/lib/spack/spack/paths.py
index f78d81fa15f..f68c1ada867 100644
--- a/lib/spack/spack/paths.py
+++ b/lib/spack/spack/paths.py
@@ -58,7 +58,7 @@
 repos_path = os.path.join(var_path, "repos")
 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")
+mock_packages_path = os.path.join(test_repos_path, "spack_repo", "builtin_mock")
 
 #
 # Writable things in $spack/var/spack
diff --git a/lib/spack/spack/repo.py b/lib/spack/spack/repo.py
index 394aaf6b404..268107b61f8 100644
--- a/lib/spack/spack/repo.py
+++ b/lib/spack/spack/repo.py
@@ -153,7 +153,7 @@ def compute_loader(self, fullname: str):
 def builtin_repo() -> "Repo":
     """Get the test repo if it is active, otherwise the builtin repo."""
     try:
-        return PATH.get_repo("builtin.mock")
+        return PATH.get_repo("builtin_mock")
     except UnknownNamespaceError:
         return PATH.get_repo("builtin")
 
diff --git a/lib/spack/spack/test/builder.py b/lib/spack/spack/test/builder.py
index 6e033951a2a..d643141276c 100644
--- a/lib/spack/spack/test/builder.py
+++ b/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.test_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
 
diff --git a/lib/spack/spack/test/cmd/ci.py b/lib/spack/spack/test/cmd/ci.py
index 4cd70c58353..e5ad3718482 100644
--- a/lib/spack/spack/test/cmd/ci.py
+++ b/lib/spack/spack/test/cmd/ci.py
@@ -136,7 +136,7 @@ def test_ci_generate_with_env(ci_generate_test, tmp_path, mock_binary_index):
     - old-gcc-pkgs:
       - archive-files
       - callpath
-      # specify ^openblas-with-lapack to ensure that builtin.mock repo flake8
+      # specify ^openblas-with-lapack to ensure that builtin_mock repo flake8
       # package (which can also provide lapack) is not chosen, as it violates
       # a package-level check which requires exactly one fetch strategy (this
       # is apparently not an issue for other tests that use it).
diff --git a/lib/spack/spack/test/cmd/env.py b/lib/spack/spack/test/cmd/env.py
index 266ebc58330..daa2d9f97f8 100644
--- a/lib/spack/spack/test/cmd/env.py
+++ b/lib/spack/spack/test/cmd/env.py
@@ -886,12 +886,12 @@ def test_env_activate_broken_view(
     with spack.repo.use_repositories(mock_custom_repository):
         wrong_repo = env("activate", "--sh", "test")
         assert "Warning: could not load runtime environment" in wrong_repo
-        assert "Unknown namespace: builtin.mock" in wrong_repo
+        assert "Unknown namespace: builtin_mock" in wrong_repo
 
     # test replacing repo fixes it
     normal_repo = env("activate", "--sh", "test")
     assert "Warning: could not load runtime environment" not in normal_repo
-    assert "Unknown namespace: builtin.mock" not in normal_repo
+    assert "Unknown namespace: builtin_mock" not in normal_repo
 
 
 def test_to_lockfile_dict():
@@ -916,7 +916,7 @@ def test_env_repo():
 
     pkg_cls = e.repo.get_pkg_class("mpileaks")
     assert pkg_cls.name == "mpileaks"
-    assert pkg_cls.namespace == "builtin.mock"
+    assert pkg_cls.namespace == "builtin_mock"
 
 
 def test_user_removed_spec(environment_from_manifest):
diff --git a/lib/spack/spack/test/cmd/external.py b/lib/spack/spack/test/cmd/external.py
index 7c4b871d6b9..10ac48414a3 100644
--- a/lib/spack/spack/test/cmd/external.py
+++ b/lib/spack/spack/test/cmd/external.py
@@ -123,24 +123,24 @@ def test_find_external_cmd_not_buildable(mutable_config, working_env, mock_execu
             ["detectable"],
             [],
             [
-                "builtin.mock.find-externals1",
-                "builtin.mock.gcc",
-                "builtin.mock.llvm",
-                "builtin.mock.intel-oneapi-compilers",
+                "builtin_mock.find-externals1",
+                "builtin_mock.gcc",
+                "builtin_mock.llvm",
+                "builtin_mock.intel-oneapi-compilers",
             ],
         ),
         # find --all --exclude find-externals1
         (
             None,
             ["detectable"],
-            ["builtin.mock.find-externals1"],
-            ["builtin.mock.gcc", "builtin.mock.llvm", "builtin.mock.intel-oneapi-compilers"],
+            ["builtin_mock.find-externals1"],
+            ["builtin_mock.gcc", "builtin_mock.llvm", "builtin_mock.intel-oneapi-compilers"],
         ),
         (
             None,
             ["detectable"],
             ["find-externals1"],
-            ["builtin.mock.gcc", "builtin.mock.llvm", "builtin.mock.intel-oneapi-compilers"],
+            ["builtin_mock.gcc", "builtin_mock.llvm", "builtin_mock.intel-oneapi-compilers"],
         ),
         # find cmake (and cmake is not detectable)
         (["cmake"], ["detectable"], [], []),
diff --git a/lib/spack/spack/test/cmd/find.py b/lib/spack/spack/test/cmd/find.py
index f01ec5666b7..2c298913110 100644
--- a/lib/spack/spack/test/cmd/find.py
+++ b/lib/spack/spack/test/cmd/find.py
@@ -129,7 +129,7 @@ def test_tag2_tag3(parser, specs):
 @pytest.mark.db
 def test_namespaces_shown_correctly(args, with_namespace, database):
     """Test that --namespace(s) works. Old syntax is --namespace"""
-    assert ("builtin.mock.zmpi" in find(*args)) == with_namespace
+    assert ("builtin_mock.zmpi" in find(*args)) == with_namespace
 
 
 @pytest.mark.db
diff --git a/lib/spack/spack/test/cmd/list.py b/lib/spack/spack/test/cmd/list.py
index d6260b51e22..b89945e6512 100644
--- a/lib/spack/spack/test/cmd/list.py
+++ b/lib/spack/spack/test/cmd/list.py
@@ -143,13 +143,13 @@ def test_list_count():
 
 def test_list_repos():
     with spack.repo.use_repositories(
-        os.path.join(spack.paths.test_repos_path, "builtin.mock"),
-        os.path.join(spack.paths.test_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())
-        builder_pkgs = len(list("-r", "builder.test").strip().split())
-        both_repos = len(list("-r", "builtin.mock", "-r", "builder.test").strip().split())
+        mock_pkgs = len(list("-r", "builtin_mock").strip().split())
+        builder_pkgs = len(list("-r", "builder_test").strip().split())
+        both_repos = len(list("-r", "builtin_mock", "-r", "builder_test").strip().split())
 
         assert total_pkgs > mock_pkgs > builder_pkgs
         assert both_repos == total_pkgs
diff --git a/lib/spack/spack/test/cmd/pkg.py b/lib/spack/spack/test/cmd/pkg.py
index 3e939d8dc3b..966d85fef80 100644
--- a/lib/spack/spack/test/cmd/pkg.py
+++ b/lib/spack/spack/test/cmd/pkg.py
@@ -37,9 +37,9 @@ def install(self, spec, prefix):
 # Force all tests to use a git repository *in* the mock packages repo.
 @pytest.fixture(scope="module")
 def mock_pkg_git_repo(git, tmp_path_factory):
-    """Copy the builtin.mock repo and make a mutable git repo inside it."""
+    """Copy the builtin_mock repo and make a mutable git repo inside it."""
     root_dir = tmp_path_factory.mktemp("mock_pkg_git_repo")
-    repo_dir = root_dir / "builtin.mock"
+    repo_dir = root_dir / "builtin_mock"
     shutil.copytree(spack.paths.mock_packages_path, str(repo_dir))
 
     repo_cache = spack.util.file_cache.FileCache(root_dir / "cache")
@@ -90,7 +90,7 @@ def mock_pkg_git_repo(git, tmp_path_factory):
 
 @pytest.fixture(scope="module")
 def mock_pkg_names():
-    repo = spack.repo.PATH.get_repo("builtin.mock")
+    repo = spack.repo.PATH.get_repo("builtin_mock")
 
     # Be sure to include virtual packages since packages with stand-alone
     # tests may inherit additional tests from the virtuals they provide,
@@ -116,7 +116,7 @@ def test_builtin_repo():
 
 
 def test_mock_builtin_repo(mock_packages):
-    assert spack.repo.builtin_repo() is spack.repo.PATH.get_repo("builtin.mock")
+    assert spack.repo.builtin_repo() is spack.repo.PATH.get_repo("builtin_mock")
 
 
 def test_pkg_add(git, mock_pkg_git_repo):
diff --git a/lib/spack/spack/test/cmd/resource.py b/lib/spack/spack/test/cmd/resource.py
index b3502edee3b..053bbbbd924 100644
--- a/lib/spack/spack/test/cmd/resource.py
+++ b/lib/spack/spack/test/cmd/resource.py
@@ -48,11 +48,11 @@ def test_resource_list(mock_packages, capfd):
     assert "path:" in out
 
     assert (
-        os.path.join("repos", "builtin.mock", "packages", "patch-a-dependency", "libelf.patch")
+        os.path.join("repos", "builtin_mock", "packages", "patch-a-dependency", "libelf.patch")
         in out
     )
-    assert "applies to: builtin.mock.libelf" in out
-    assert "patched by: builtin.mock.patch-a-dependency" in out
+    assert "applies to: builtin_mock.libelf" in out
+    assert "patched by: builtin_mock.patch-a-dependency" in out
 
 
 def test_resource_list_only_hashes(mock_packages, capfd):
@@ -74,10 +74,10 @@ def test_resource_show(mock_packages, capfd):
 
     assert out.startswith(test_hash)
     assert (
-        os.path.join("repos", "builtin.mock", "packages", "patch-a-dependency", "libelf.patch")
+        os.path.join("repos", "builtin_mock", "packages", "patch-a-dependency", "libelf.patch")
         in out
     )
-    assert "applies to: builtin.mock.libelf" in out
-    assert "patched by: builtin.mock.patch-a-dependency" in out
+    assert "applies to: builtin_mock.libelf" in out
+    assert "patched by: builtin_mock.patch-a-dependency" in out
 
     assert len(out.strip().split("\n")) == 4
diff --git a/lib/spack/spack/test/cmd/versions.py b/lib/spack/spack/test/cmd/versions.py
index c42ae636df9..bc85f23f656 100644
--- a/lib/spack/spack/test/cmd/versions.py
+++ b/lib/spack/spack/test/cmd/versions.py
@@ -36,7 +36,7 @@ def test_remote_versions_only():
 @pytest.mark.usefixtures("mock_packages")
 def test_new_versions_only(monkeypatch):
     """Test a package for which new versions should be available."""
-    from spack.pkg.builtin.mock.brillig import Brillig  # type: ignore[import]
+    from spack.pkg.builtin_mock.brillig import Brillig  # type: ignore[import]
 
     def mock_fetch_remote_versions(*args, **kwargs):
         mock_remote_versions = {
diff --git a/lib/spack/spack/test/concretization/compiler_runtimes.py b/lib/spack/spack/test/concretization/compiler_runtimes.py
index 68a94c812aa..455f27a4a66 100644
--- a/lib/spack/spack/test/concretization/compiler_runtimes.py
+++ b/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.test_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
 
diff --git a/lib/spack/spack/test/concretization/core.py b/lib/spack/spack/test/concretization/core.py
index 04bfbf23f09..85743aad4ce 100644
--- a/lib/spack/spack/test/concretization/core.py
+++ b/lib/spack/spack/test/concretization/core.py
@@ -78,7 +78,7 @@ def binary_compatibility(monkeypatch, request):
         return
 
     if "mock_packages" not in request.fixturenames:
-        # Only builtin.mock has a mock glibc package
+        # Only builtin_mock has a mock glibc package
         return
 
     if "database" in request.fixturenames or "mutable_database" in request.fixturenames:
@@ -373,11 +373,11 @@ def test_provides_handles_multiple_providers_of_same_version(self):
         # Note that providers are repo-specific, so we don't misinterpret
         # providers, but vdeps are not namespace-specific, so we can
         # associate vdeps across repos.
-        assert Spec("builtin.mock.multi-provider-mpi@1.10.3") in providers
-        assert Spec("builtin.mock.multi-provider-mpi@1.10.2") in providers
-        assert Spec("builtin.mock.multi-provider-mpi@1.10.1") in providers
-        assert Spec("builtin.mock.multi-provider-mpi@1.10.0") in providers
-        assert Spec("builtin.mock.multi-provider-mpi@1.8.8") in providers
+        assert Spec("builtin_mock.multi-provider-mpi@1.10.3") in providers
+        assert Spec("builtin_mock.multi-provider-mpi@1.10.2") in providers
+        assert Spec("builtin_mock.multi-provider-mpi@1.10.1") in providers
+        assert Spec("builtin_mock.multi-provider-mpi@1.10.0") in providers
+        assert Spec("builtin_mock.multi-provider-mpi@1.8.8") in providers
 
     def test_different_compilers_get_different_flags(
         self, mutable_config, clang12_with_flags, gcc11_with_flags
@@ -1715,12 +1715,12 @@ def test_reuse_with_unknown_namespace_dont_raise(
     ):
         with spack.repo.use_repositories(mock_custom_repository, override=False):
             s = spack.concretize.concretize_one("pkg-c")
-            assert s.namespace != "builtin.mock"
+            assert s.namespace != "builtin_mock"
             PackageInstaller([s.package], fake=True, explicit=True).install()
 
         with spack.config.override("concretizer:reuse", True):
             s = spack.concretize.concretize_one("pkg-c")
-        assert s.namespace == "builtin.mock"
+        assert s.namespace == "builtin_mock"
 
     @pytest.mark.regression("45538")
     def test_reuse_from_other_namespace_no_raise(self, tmpdir, temporary_store, monkeypatch):
@@ -1751,7 +1751,7 @@ def test_reuse_with_unknown_package_dont_raise(self, tmpdir, temporary_store, mo
             repos.repos[0]._pkg_checker.invalidate()
             with spack.config.override("concretizer:reuse", True):
                 s = spack.concretize.concretize_one("pkg-c")
-            assert s.namespace == "builtin.mock"
+            assert s.namespace == "builtin_mock"
 
     @pytest.mark.parametrize(
         "specs,checks",
@@ -2328,10 +2328,10 @@ def test_reuse_python_from_cli_and_extension_from_db(self, mutable_database):
         "spec_str,expected_namespaces",
         [
             # Single node with fully qualified namespace
-            ("builtin.mock.gmake", {"gmake": "builtin.mock"}),
+            ("builtin_mock.gmake", {"gmake": "builtin_mock"}),
             # Dependency with fully qualified namespace
-            ("hdf5 ^builtin.mock.gmake", {"gmake": "builtin.mock", "hdf5": "duplicates.test"}),
-            ("hdf5 ^gmake", {"gmake": "duplicates.test", "hdf5": "duplicates.test"}),
+            ("hdf5 ^builtin_mock.gmake", {"gmake": "builtin_mock", "hdf5": "duplicates_test"}),
+            ("hdf5 ^gmake", {"gmake": "duplicates_test", "hdf5": "duplicates_test"}),
         ],
     )
     def test_select_lower_priority_package_from_repository_stack(
@@ -2340,8 +2340,8 @@ def test_select_lower_priority_package_from_repository_stack(
         """Tests that a user can explicitly select a lower priority, fully qualified dependency
         from cli.
         """
-        # 'builtin.mock" and "duplicates.test" share a 'gmake' package
-        additional_repo = os.path.join(spack.paths.test_repos_path, "duplicates.test")
+        # 'builtin_mock" and "duplicates_test" share a 'gmake' package
+        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)
 
@@ -2585,7 +2585,7 @@ 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.test_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
 
@@ -2820,7 +2820,7 @@ def test_adding_specs(self, input_specs, default_mock_concretization):
 
 @pytest.fixture()
 def edges_test_repository():
-    repository_path = os.path.join(spack.paths.test_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
 
diff --git a/lib/spack/spack/test/concretization/flag_mixing.py b/lib/spack/spack/test/concretization/flag_mixing.py
index 0b79f88a991..0c479949e48 100644
--- a/lib/spack/spack/test/concretization/flag_mixing.py
+++ b/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.test_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
 
diff --git a/lib/spack/spack/test/concretization/requirements.py b/lib/spack/spack/test/concretization/requirements.py
index cae5cb760a0..d8dd9a07d87 100644
--- a/lib/spack/spack/test/concretization/requirements.py
+++ b/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.test_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
 
diff --git a/lib/spack/spack/test/conftest.py b/lib/spack/spack/test/conftest.py
index b5b8e4d9825..beb5e5eedcb 100644
--- a/lib/spack/spack/test/conftest.py
+++ b/lib/spack/spack/test/conftest.py
@@ -654,7 +654,7 @@ def mock_pkg_install(monkeypatch):
 
 @pytest.fixture(scope="function")
 def mock_packages(mock_repo_path, mock_pkg_install, request):
-    """Use the 'builtin.mock' repository instead of 'builtin'"""
+    """Use the 'builtin_mock' repository instead of 'builtin'"""
     ensure_configuration_fixture_run_before(request)
     with spack.repo.use_repositories(mock_repo_path) as mock_repo:
         yield mock_repo
@@ -1433,7 +1433,7 @@ def mock_git_repository(git, tmpdir_factory):
     of these refers to a repository with a single commit.
 
     c0, c1, and c2 include information to define explicit versions in the
-    associated builtin.mock package 'git-test'. c3 is a commit in the
+    associated builtin_mock package 'git-test'. c3 is a commit in the
     repository but does not have an associated explicit package version.
     """
     suburls = []
diff --git a/lib/spack/spack/test/packages.py b/lib/spack/spack/test/packages.py
index 52b476e376f..908663b08af 100644
--- a/lib/spack/spack/test/packages.py
+++ b/lib/spack/spack/test/packages.py
@@ -60,12 +60,12 @@ def test_package_class_names(self):
     # Below tests target direct imports of spack packages from the
     # spack.pkg namespace
     def test_import_package(self):
-        import spack.pkg.builtin.mock.mpich  # type: ignore[import] # noqa: F401
+        import spack.pkg.builtin_mock.mpich  # type: ignore[import] # noqa: F401
 
     def test_import_package_as(self):
-        import spack.pkg.builtin.mock  # noqa: F401
-        import spack.pkg.builtin.mock as m  # noqa: F401
-        import spack.pkg.builtin.mock.mpich as mp  # noqa: F401
+        import spack.pkg.builtin_mock  # noqa: F401
+        import spack.pkg.builtin_mock as m  # noqa: F401
+        import spack.pkg.builtin_mock.mpich as mp  # noqa: F401
         from spack.pkg.builtin import mock  # noqa: F401
 
     def test_inheritance_of_directives(self):
@@ -98,18 +98,18 @@ def test_inheritance_of_patches(self):
         _ = spack.concretize.concretize_one("patch-inheritance")
 
     def test_import_class_from_package(self):
-        from spack.pkg.builtin.mock.mpich import Mpich  # noqa: F401
+        from spack.pkg.builtin_mock.mpich import Mpich  # noqa: F401
 
     def test_import_module_from_package(self):
-        from spack.pkg.builtin.mock import mpich  # noqa: F401
+        from spack.pkg.builtin_mock import mpich  # noqa: F401
 
     def test_import_namespace_container_modules(self):
         import spack.pkg  # noqa: F401
         import spack.pkg as p  # noqa: F401
         import spack.pkg.builtin  # noqa: F401
         import spack.pkg.builtin as b  # noqa: F401
-        import spack.pkg.builtin.mock  # noqa: F401
-        import spack.pkg.builtin.mock as m  # noqa: F401
+        import spack.pkg.builtin_mock  # noqa: F401
+        import spack.pkg.builtin_mock as m  # noqa: F401
         from spack import pkg  # noqa: F401
         from spack.pkg import builtin  # noqa: F401
         from spack.pkg.builtin import mock  # noqa: F401
diff --git a/lib/spack/spack/test/patch.py b/lib/spack/spack/test/patch.py
index 7afdd4b5f96..df7353f6ffa 100644
--- a/lib/spack/spack/test/patch.py
+++ b/lib/spack/spack/test/patch.py
@@ -360,11 +360,11 @@ def get_patch(spec, ending):
     assert foo_patch.path == os.path.join(package_dir, "foo.patch")
     assert foo_patch.sha256 == foo_sha256
 
-    assert bar_patch.owner == "builtin.mock.patch-several-dependencies"
+    assert bar_patch.owner == "builtin_mock.patch-several-dependencies"
     assert bar_patch.path == os.path.join(package_dir, "bar.patch")
     assert bar_patch.sha256 == bar_sha256
 
-    assert baz_patch.owner == "builtin.mock.patch-several-dependencies"
+    assert baz_patch.owner == "builtin_mock.patch-several-dependencies"
     assert baz_patch.path == os.path.join(package_dir, "baz.patch")
     assert baz_patch.sha256 == baz_sha256
 
@@ -376,11 +376,11 @@ def get_patch(spec, ending):
     url1_patch = get_patch(fake, "urlpatch.patch")
     url2_patch = get_patch(fake, "urlpatch2.patch.gz")
 
-    assert url1_patch.owner == "builtin.mock.patch-several-dependencies"
+    assert url1_patch.owner == "builtin_mock.patch-several-dependencies"
     assert url1_patch.url == "http://example.com/urlpatch.patch"
     assert url1_patch.sha256 == url1_sha256
 
-    assert url2_patch.owner == "builtin.mock.patch-several-dependencies"
+    assert url2_patch.owner == "builtin_mock.patch-several-dependencies"
     assert url2_patch.url == "http://example.com/urlpatch2.patch.gz"
     assert url2_patch.sha256 == url2_sha256
     assert url2_patch.archive_sha256 == url2_archive_sha256
@@ -397,7 +397,7 @@ def test_conditional_patched_deps_with_conditions(mock_packages, config):
     fake = spec["fake"]
 
     check_multi_dependency_patch_specs(
-        libelf, libdwarf, fake, "builtin.mock.patch-several-dependencies", spec.package.package_dir
+        libelf, libdwarf, fake, "builtin_mock.patch-several-dependencies", spec.package.package_dir
     )
 
 
@@ -417,7 +417,7 @@ def test_write_and_read_sub_dags_with_patched_deps(mock_packages, config):
 
     # make sure we can still read patches correctly for these specs
     check_multi_dependency_patch_specs(
-        libelf, libdwarf, fake, "builtin.mock.patch-several-dependencies", spec.package.package_dir
+        libelf, libdwarf, fake, "builtin_mock.patch-several-dependencies", spec.package.package_dir
     )
 
 
diff --git a/lib/spack/spack/test/repo.py b/lib/spack/spack/test/repo.py
index 13a3cb63de1..9322516ca3c 100644
--- a/lib/spack/spack/test/repo.py
+++ b/lib/spack/spack/test/repo.py
@@ -43,19 +43,19 @@ def extra_repo(tmp_path_factory, request):
 
 def test_repo_getpkg(mutable_mock_repo):
     mutable_mock_repo.get_pkg_class("pkg-a")
-    mutable_mock_repo.get_pkg_class("builtin.mock.pkg-a")
+    mutable_mock_repo.get_pkg_class("builtin_mock.pkg-a")
 
 
 def test_repo_multi_getpkg(mutable_mock_repo, extra_repo):
     mutable_mock_repo.put_first(extra_repo[0])
     mutable_mock_repo.get_pkg_class("pkg-a")
-    mutable_mock_repo.get_pkg_class("builtin.mock.pkg-a")
+    mutable_mock_repo.get_pkg_class("builtin_mock.pkg-a")
 
 
 def test_repo_multi_getpkgclass(mutable_mock_repo, extra_repo):
     mutable_mock_repo.put_first(extra_repo[0])
     mutable_mock_repo.get_pkg_class("pkg-a")
-    mutable_mock_repo.get_pkg_class("builtin.mock.pkg-a")
+    mutable_mock_repo.get_pkg_class("builtin_mock.pkg-a")
 
 
 def test_repo_pkg_with_unknown_namespace(mutable_mock_repo):
@@ -65,7 +65,7 @@ def test_repo_pkg_with_unknown_namespace(mutable_mock_repo):
 
 def test_repo_unknown_pkg(mutable_mock_repo):
     with pytest.raises(spack.repo.UnknownPackageError):
-        mutable_mock_repo.get_pkg_class("builtin.mock.nonexistentpackage")
+        mutable_mock_repo.get_pkg_class("builtin_mock.nonexistentpackage")
 
 
 def test_repo_last_mtime(mock_packages):
@@ -98,7 +98,7 @@ def test_repo_invisibles(mutable_mock_repo, extra_repo):
 def test_namespace_hasattr(attr_name, exists, mutable_mock_repo):
     # Check that we don't fail on 'hasattr' checks because
     # of a custom __getattr__ implementation
-    nms = spack.repo.SpackNamespace("spack.pkg.builtin.mock")
+    nms = spack.repo.SpackNamespace("spack.pkg.builtin_mock")
     assert hasattr(nms, attr_name) == exists
 
 
@@ -121,24 +121,24 @@ def test_use_repositories_doesnt_change_class(mock_packages):
 
 
 def test_import_repo_prefixes_as_python_modules(mock_packages):
-    import spack.pkg.builtin.mock
+    import spack.pkg.builtin_mock
 
     assert isinstance(spack.pkg, spack.repo.SpackNamespace)
     assert isinstance(spack.pkg.builtin, spack.repo.SpackNamespace)
-    assert isinstance(spack.pkg.builtin.mock, spack.repo.SpackNamespace)
+    assert isinstance(spack.pkg.builtin_mock, spack.repo.SpackNamespace)
 
 
 def test_absolute_import_spack_packages_as_python_modules(mock_packages):
-    import spack.pkg.builtin.mock.mpileaks
+    import spack.pkg.builtin_mock.mpileaks
 
-    assert hasattr(spack.pkg.builtin.mock, "mpileaks")
-    assert hasattr(spack.pkg.builtin.mock.mpileaks, "Mpileaks")
-    assert isinstance(spack.pkg.builtin.mock.mpileaks.Mpileaks, spack.package_base.PackageMeta)
-    assert issubclass(spack.pkg.builtin.mock.mpileaks.Mpileaks, spack.package_base.PackageBase)
+    assert hasattr(spack.pkg.builtin_mock, "mpileaks")
+    assert hasattr(spack.pkg.builtin_mock.mpileaks, "Mpileaks")
+    assert isinstance(spack.pkg.builtin_mock.mpileaks.Mpileaks, spack.package_base.PackageMeta)
+    assert issubclass(spack.pkg.builtin_mock.mpileaks.Mpileaks, spack.package_base.PackageBase)
 
 
 def test_relative_import_spack_packages_as_python_modules(mock_packages):
-    from spack.pkg.builtin.mock.mpileaks import Mpileaks
+    from spack.pkg.builtin_mock.mpileaks import Mpileaks
 
     assert isinstance(Mpileaks, spack.package_base.PackageMeta)
     assert issubclass(Mpileaks, spack.package_base.PackageBase)
@@ -160,7 +160,7 @@ def test_repo_path_handles_package_removal(tmpdir, mock_packages):
     builder.remove("pkg-c")
     with spack.repo.use_repositories(builder.root, override=False) as repos:
         r = repos.repo_for_pkg("pkg-c")
-        assert r.namespace == "builtin.mock"
+        assert r.namespace == "builtin_mock"
 
 
 def test_repo_dump_virtuals(tmpdir, mutable_mock_repo, mock_packages, ensure_debug, capsys):
@@ -185,7 +185,7 @@ def _repo_paths(repos):
         for entry in repos:
             if entry == "mock":
                 repo_paths.append(spack.paths.mock_packages_path)
-                namespaces.append("builtin.mock")
+                namespaces.append("builtin_mock")
             if entry == "extra":
                 name = "extra_mock"
                 repo_dir = tmp_path / name
@@ -211,7 +211,7 @@ def test_path_computation_with_names(method_name, mock_repo_path):
     repo_path = spack.repo.RepoPath(mock_repo_path, cache=None)
     method = getattr(repo_path, method_name)
     unqualified = method("mpileaks")
-    qualified = method("builtin.mock.mpileaks")
+    qualified = method("builtin_mock.mpileaks")
     assert qualified == unqualified
 
 
@@ -220,11 +220,11 @@ def test_use_repositories_and_import():
     import spack.paths
 
     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
+    with spack.repo.use_repositories(str(repo_dir / "compiler_runtime_test")):
+        import spack.pkg.compiler_runtime_test.gcc_runtime
 
-    with spack.repo.use_repositories(str(repo_dir / "builtin.mock")):
-        import spack.pkg.builtin.mock.cmake
+    with spack.repo.use_repositories(str(repo_dir / "builtin_mock")):
+        import spack.pkg.builtin_mock.cmake
 
 
 @pytest.mark.usefixtures("nullify_globals")
@@ -236,7 +236,7 @@ class TestRepo:
     def test_creation(self, mock_test_cache):
         repo = spack.repo.Repo(spack.paths.mock_packages_path, cache=mock_test_cache)
         assert repo.config_file.endswith("repo.yaml")
-        assert repo.namespace == "builtin.mock"
+        assert repo.namespace == "builtin_mock"
 
     @pytest.mark.parametrize(
         "name,expected", [("mpi", True), ("mpich", False), ("mpileaks", False)]
@@ -312,12 +312,12 @@ class TestRepoPath:
     def test_creation_from_string(self, mock_test_cache):
         repo = spack.repo.RepoPath(spack.paths.mock_packages_path, cache=mock_test_cache)
         assert len(repo.repos) == 1
-        assert repo.by_namespace["builtin.mock"] is repo.repos[0]
+        assert repo.by_namespace["builtin_mock"] is repo.repos[0]
 
     def test_get_repo(self, mock_test_cache):
         repo = spack.repo.RepoPath(spack.paths.mock_packages_path, cache=mock_test_cache)
-        # builtin.mock is there
-        assert repo.get_repo("builtin.mock") is repo.repos[0]
+        # builtin_mock is there
+        assert repo.get_repo("builtin_mock") is repo.repos[0]
         # foo is not there, raise
         with pytest.raises(spack.repo.UnknownNamespaceError):
             repo.get_repo("foo")
diff --git a/lib/spack/spack/test/spec_semantics.py b/lib/spack/spack/test/spec_semantics.py
index 70bbb7fb078..cb77270e641 100644
--- a/lib/spack/spack/test/spec_semantics.py
+++ b/lib/spack/spack/test/spec_semantics.py
@@ -135,16 +135,16 @@ class TestSpecSemantics:
             ("libelf@0:2.5%gcc@2:4.6", "libelf@2.1:3%gcc@4.5:4.7", "libelf@2.1:2.5%gcc@4.5:4.6"),
             # Namespaces
             ("builtin.mpich", "mpich", "builtin.mpich"),
-            ("builtin.mock.mpich", "mpich", "builtin.mock.mpich"),
+            ("builtin_mock.mpich", "mpich", "builtin_mock.mpich"),
             ("builtin.mpich", "builtin.mpich", "builtin.mpich"),
-            ("mpileaks ^builtin.mock.mpich", "^mpich", "mpileaks ^builtin.mock.mpich"),
+            ("mpileaks ^builtin_mock.mpich", "^mpich", "mpileaks ^builtin_mock.mpich"),
             # Virtual dependencies are fully resolved during concretization, so we can constrain
             # abstract specs but that would result in a new node
-            ("mpileaks ^builtin.mock.mpich", "^mpi", "mpileaks ^mpi ^builtin.mock.mpich"),
+            ("mpileaks ^builtin_mock.mpich", "^mpi", "mpileaks ^mpi ^builtin_mock.mpich"),
             (
-                "mpileaks ^builtin.mock.mpich",
-                "^builtin.mock.mpich",
-                "mpileaks ^builtin.mock.mpich",
+                "mpileaks ^builtin_mock.mpich",
+                "^builtin_mock.mpich",
+                "mpileaks ^builtin_mock.mpich",
             ),
             # Compilers
             ("foo%gcc", "%gcc", "foo%gcc"),
@@ -455,8 +455,8 @@ def test_concrete_specs_which_satisfies_abstract(self, lhs, rhs, default_mock_co
             ("foo%gcc@4.3", "%gcc@4.4:4.6"),
             ("foo@4.0%gcc", "@1:3%gcc"),
             ("foo@4.0%gcc@4.5", "@1:3%gcc@4.4:4.6"),
-            ("builtin.mock.mpich", "builtin.mpich"),
-            ("mpileaks ^builtin.mock.mpich", "^builtin.mpich"),
+            ("builtin_mock.mpich", "builtin.mpich"),
+            ("mpileaks ^builtin_mock.mpich", "^builtin.mpich"),
             ("mpileaks^mpich@1.2", "^mpich@2.0"),
             ("mpileaks^mpich@4.0^callpath@1.5", "^mpich@1:3^callpath@1.4:1.6"),
             ("mpileaks^mpich@2.0^callpath@1.7", "^mpich@1:3^callpath@1.4:1.6"),
@@ -476,7 +476,7 @@ def test_concrete_specs_which_satisfies_abstract(self, lhs, rhs, default_mock_co
             ("libelf+debug", "libelf~debug"),
             ("libelf+debug~foo", "libelf+debug+foo"),
             ("libelf debug=True", "libelf debug=False"),
-            ("namespace=builtin.mock", "namespace=builtin"),
+            ("namespace=builtin_mock", "namespace=builtin"),
         ],
     )
     def test_constraining_abstract_specs_with_empty_intersection(self, lhs, rhs):
@@ -609,7 +609,7 @@ def test_indirect_unsatisfied_single_valued_variant(self):
 
     def test_satisfied_namespace(self):
         spec = spack.concretize.concretize_one("zlib")
-        assert spec.satisfies("namespace=builtin.mock")
+        assert spec.satisfies("namespace=builtin_mock")
         assert not spec.satisfies("namespace=builtin")
 
     @pytest.mark.parametrize(
diff --git a/lib/spack/spack/test/spec_syntax.py b/lib/spack/spack/test/spec_syntax.py
index d3ac7344cce..5c658e61985 100644
--- a/lib/spack/spack/test/spec_syntax.py
+++ b/lib/spack/spack/test/spec_syntax.py
@@ -1185,7 +1185,7 @@ def test_parse_filename_missing_slash_as_spec(specfile_for, tmpdir, filename):
 
     # make sure that only happens when the spec ends in yaml
     with pytest.raises(spack.solver.asp.UnsatisfiableSpecError) as exc_info:
-        spack.concretize.concretize_one(SpecParser("builtin.mock.doesnotexist").next_spec())
+        spack.concretize.concretize_one(SpecParser("builtin_mock.doesnotexist").next_spec())
     assert not exc_info.value.long_message or (
         "Did you mean to specify a filename with" not in exc_info.value.long_message
     )
diff --git a/lib/spack/spack/test/spec_yaml.py b/lib/spack/spack/test/spec_yaml.py
index 3652d960673..24b5c412b38 100644
--- a/lib/spack/spack/test/spec_yaml.py
+++ b/lib/spack/spack/test/spec_yaml.py
@@ -266,7 +266,7 @@ def test_legacy_yaml(tmpdir, install_mockery, mock_packages):
     compiler:
       name: gcc
       version: 8.3.0
-    namespace: builtin.mock
+    namespace: builtin_mock
     parameters:
       bvv: true
       foo:
@@ -296,7 +296,7 @@ def test_legacy_yaml(tmpdir, install_mockery, mock_packages):
     compiler:
       name: gcc
       version: 8.3.0
-    namespace: builtin.mock
+    namespace: builtin_mock
     parameters:
       cflags: []
       cppflags: []
diff --git a/var/spack/test_repos/builder.test/repo.yaml b/var/spack/test_repos/builder.test/repo.yaml
deleted file mode 100644
index a9031afe214..00000000000
--- a/var/spack/test_repos/builder.test/repo.yaml
+++ /dev/null
@@ -1,2 +0,0 @@
-repo:
-  namespace: builder.test
diff --git a/var/spack/test_repos/builtin.mock/packages/compiler-wrapper b/var/spack/test_repos/builtin.mock/packages/compiler-wrapper
deleted file mode 120000
index 3dbeed1bd41..00000000000
--- a/var/spack/test_repos/builtin.mock/packages/compiler-wrapper
+++ /dev/null
@@ -1 +0,0 @@
-../../../repos/spack_repo/builtin/packages/compiler_wrapper
\ No newline at end of file
diff --git a/var/spack/test_repos/builtin.mock/packages/gcc-runtime b/var/spack/test_repos/builtin.mock/packages/gcc-runtime
deleted file mode 120000
index 4b89579f1e6..00000000000
--- a/var/spack/test_repos/builtin.mock/packages/gcc-runtime
+++ /dev/null
@@ -1 +0,0 @@
-../../../repos/spack_repo/builtin/packages/gcc_runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/builtin.mock/repo.yaml b/var/spack/test_repos/builtin.mock/repo.yaml
deleted file mode 100644
index 30b068da13d..00000000000
--- a/var/spack/test_repos/builtin.mock/repo.yaml
+++ /dev/null
@@ -1,2 +0,0 @@
-repo:
-  namespace: builtin.mock
diff --git a/var/spack/test_repos/compiler_runtime.test/packages/compiler-wrapper b/var/spack/test_repos/compiler_runtime.test/packages/compiler-wrapper
deleted file mode 120000
index 7e103b3d9e2..00000000000
--- a/var/spack/test_repos/compiler_runtime.test/packages/compiler-wrapper
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/compiler-wrapper
\ No newline at end of file
diff --git a/var/spack/test_repos/compiler_runtime.test/packages/gcc b/var/spack/test_repos/compiler_runtime.test/packages/gcc
deleted file mode 120000
index 17e3b9e575b..00000000000
--- a/var/spack/test_repos/compiler_runtime.test/packages/gcc
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gcc
\ No newline at end of file
diff --git a/var/spack/test_repos/compiler_runtime.test/packages/gcc-runtime b/var/spack/test_repos/compiler_runtime.test/packages/gcc-runtime
deleted file mode 120000
index 0e770302bf4..00000000000
--- a/var/spack/test_repos/compiler_runtime.test/packages/gcc-runtime
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gcc-runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/compiler_runtime.test/packages/glibc b/var/spack/test_repos/compiler_runtime.test/packages/glibc
deleted file mode 120000
index f9cd337cc24..00000000000
--- a/var/spack/test_repos/compiler_runtime.test/packages/glibc
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/glibc
\ No newline at end of file
diff --git a/var/spack/test_repos/compiler_runtime.test/packages/gmake b/var/spack/test_repos/compiler_runtime.test/packages/gmake
deleted file mode 120000
index 86bbc3dd35a..00000000000
--- a/var/spack/test_repos/compiler_runtime.test/packages/gmake
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gmake
\ No newline at end of file
diff --git a/var/spack/test_repos/compiler_runtime.test/packages/gnuconfig b/var/spack/test_repos/compiler_runtime.test/packages/gnuconfig
deleted file mode 120000
index cfb894494bd..00000000000
--- a/var/spack/test_repos/compiler_runtime.test/packages/gnuconfig
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gnuconfig
\ No newline at end of file
diff --git a/var/spack/test_repos/compiler_runtime.test/repo.yaml b/var/spack/test_repos/compiler_runtime.test/repo.yaml
deleted file mode 100644
index 1be826a641f..00000000000
--- a/var/spack/test_repos/compiler_runtime.test/repo.yaml
+++ /dev/null
@@ -1,2 +0,0 @@
-repo:
-  namespace: compiler_runtime.test
diff --git a/var/spack/test_repos/duplicates.test/packages/compiler-wrapper b/var/spack/test_repos/duplicates.test/packages/compiler-wrapper
deleted file mode 120000
index 7e103b3d9e2..00000000000
--- a/var/spack/test_repos/duplicates.test/packages/compiler-wrapper
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/compiler-wrapper
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/gcc b/var/spack/test_repos/duplicates.test/packages/gcc
deleted file mode 120000
index 17e3b9e575b..00000000000
--- a/var/spack/test_repos/duplicates.test/packages/gcc
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gcc
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/gcc-runtime b/var/spack/test_repos/duplicates.test/packages/gcc-runtime
deleted file mode 120000
index 0e770302bf4..00000000000
--- a/var/spack/test_repos/duplicates.test/packages/gcc-runtime
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gcc-runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/glibc b/var/spack/test_repos/duplicates.test/packages/glibc
deleted file mode 120000
index f9cd337cc24..00000000000
--- a/var/spack/test_repos/duplicates.test/packages/glibc
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/glibc
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/gnuconfig b/var/spack/test_repos/duplicates.test/packages/gnuconfig
deleted file mode 120000
index cfb894494bd..00000000000
--- a/var/spack/test_repos/duplicates.test/packages/gnuconfig
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gnuconfig
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/llvm b/var/spack/test_repos/duplicates.test/packages/llvm
deleted file mode 120000
index 7dddef3a960..00000000000
--- a/var/spack/test_repos/duplicates.test/packages/llvm
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/llvm
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/python-venv b/var/spack/test_repos/duplicates.test/packages/python-venv
deleted file mode 120000
index a9a1ce867a8..00000000000
--- a/var/spack/test_repos/duplicates.test/packages/python-venv
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/python-venv
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/repo.yaml b/var/spack/test_repos/duplicates.test/repo.yaml
deleted file mode 100644
index fd021c858cc..00000000000
--- a/var/spack/test_repos/duplicates.test/repo.yaml
+++ /dev/null
@@ -1,2 +0,0 @@
-repo:
-  namespace: duplicates.test
diff --git a/var/spack/test_repos/edges.test/packages/compiler-wrapper b/var/spack/test_repos/edges.test/packages/compiler-wrapper
deleted file mode 120000
index 7e103b3d9e2..00000000000
--- a/var/spack/test_repos/edges.test/packages/compiler-wrapper
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/compiler-wrapper
\ No newline at end of file
diff --git a/var/spack/test_repos/edges.test/packages/gcc b/var/spack/test_repos/edges.test/packages/gcc
deleted file mode 120000
index 17e3b9e575b..00000000000
--- a/var/spack/test_repos/edges.test/packages/gcc
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gcc
\ No newline at end of file
diff --git a/var/spack/test_repos/edges.test/packages/gcc-runtime b/var/spack/test_repos/edges.test/packages/gcc-runtime
deleted file mode 120000
index 0e770302bf4..00000000000
--- a/var/spack/test_repos/edges.test/packages/gcc-runtime
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gcc-runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/edges.test/packages/glibc b/var/spack/test_repos/edges.test/packages/glibc
deleted file mode 120000
index f9cd337cc24..00000000000
--- a/var/spack/test_repos/edges.test/packages/glibc
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/glibc
\ No newline at end of file
diff --git a/var/spack/test_repos/edges.test/packages/gmake b/var/spack/test_repos/edges.test/packages/gmake
deleted file mode 120000
index 86bbc3dd35a..00000000000
--- a/var/spack/test_repos/edges.test/packages/gmake
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gmake
\ No newline at end of file
diff --git a/var/spack/test_repos/edges.test/packages/gnuconfig b/var/spack/test_repos/edges.test/packages/gnuconfig
deleted file mode 120000
index cfb894494bd..00000000000
--- a/var/spack/test_repos/edges.test/packages/gnuconfig
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gnuconfig
\ No newline at end of file
diff --git a/var/spack/test_repos/edges.test/packages/llvm b/var/spack/test_repos/edges.test/packages/llvm
deleted file mode 120000
index 7dddef3a960..00000000000
--- a/var/spack/test_repos/edges.test/packages/llvm
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/llvm
\ No newline at end of file
diff --git a/var/spack/test_repos/edges.test/repo.yaml b/var/spack/test_repos/edges.test/repo.yaml
deleted file mode 100644
index 86df79affe2..00000000000
--- a/var/spack/test_repos/edges.test/repo.yaml
+++ /dev/null
@@ -1,2 +0,0 @@
-repo:
-  namespace: edges.test
diff --git a/var/spack/test_repos/flags.test/packages/compiler-wrapper b/var/spack/test_repos/flags.test/packages/compiler-wrapper
deleted file mode 120000
index 7e103b3d9e2..00000000000
--- a/var/spack/test_repos/flags.test/packages/compiler-wrapper
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/compiler-wrapper
\ No newline at end of file
diff --git a/var/spack/test_repos/flags.test/packages/gcc b/var/spack/test_repos/flags.test/packages/gcc
deleted file mode 120000
index 17e3b9e575b..00000000000
--- a/var/spack/test_repos/flags.test/packages/gcc
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gcc
\ No newline at end of file
diff --git a/var/spack/test_repos/flags.test/packages/gcc-runtime b/var/spack/test_repos/flags.test/packages/gcc-runtime
deleted file mode 120000
index 0e770302bf4..00000000000
--- a/var/spack/test_repos/flags.test/packages/gcc-runtime
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gcc-runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/flags.test/packages/glibc b/var/spack/test_repos/flags.test/packages/glibc
deleted file mode 120000
index f9cd337cc24..00000000000
--- a/var/spack/test_repos/flags.test/packages/glibc
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/glibc
\ No newline at end of file
diff --git a/var/spack/test_repos/flags.test/packages/gmake b/var/spack/test_repos/flags.test/packages/gmake
deleted file mode 120000
index eefeb5e47f5..00000000000
--- a/var/spack/test_repos/flags.test/packages/gmake
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gmake/
\ No newline at end of file
diff --git a/var/spack/test_repos/flags.test/packages/gnuconfig b/var/spack/test_repos/flags.test/packages/gnuconfig
deleted file mode 120000
index cfb894494bd..00000000000
--- a/var/spack/test_repos/flags.test/packages/gnuconfig
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gnuconfig
\ No newline at end of file
diff --git a/var/spack/test_repos/flags.test/repo.yaml b/var/spack/test_repos/flags.test/repo.yaml
deleted file mode 100644
index a87dc9ca963..00000000000
--- a/var/spack/test_repos/flags.test/repo.yaml
+++ /dev/null
@@ -1,2 +0,0 @@
-repo:
-  namespace: flags.test
diff --git a/var/spack/test_repos/requirements.test/packages/compiler-wrapper b/var/spack/test_repos/requirements.test/packages/compiler-wrapper
deleted file mode 120000
index d0feadce051..00000000000
--- a/var/spack/test_repos/requirements.test/packages/compiler-wrapper
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/compiler-wrapper/
\ No newline at end of file
diff --git a/var/spack/test_repos/requirements.test/packages/gcc b/var/spack/test_repos/requirements.test/packages/gcc
deleted file mode 120000
index 17e3b9e575b..00000000000
--- a/var/spack/test_repos/requirements.test/packages/gcc
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gcc
\ No newline at end of file
diff --git a/var/spack/test_repos/requirements.test/packages/gcc-runtime b/var/spack/test_repos/requirements.test/packages/gcc-runtime
deleted file mode 120000
index 0e770302bf4..00000000000
--- a/var/spack/test_repos/requirements.test/packages/gcc-runtime
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gcc-runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/requirements.test/packages/glibc b/var/spack/test_repos/requirements.test/packages/glibc
deleted file mode 120000
index f9cd337cc24..00000000000
--- a/var/spack/test_repos/requirements.test/packages/glibc
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/glibc
\ No newline at end of file
diff --git a/var/spack/test_repos/requirements.test/packages/gmake b/var/spack/test_repos/requirements.test/packages/gmake
deleted file mode 120000
index eefeb5e47f5..00000000000
--- a/var/spack/test_repos/requirements.test/packages/gmake
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gmake/
\ No newline at end of file
diff --git a/var/spack/test_repos/requirements.test/packages/gnuconfig b/var/spack/test_repos/requirements.test/packages/gnuconfig
deleted file mode 120000
index cfb894494bd..00000000000
--- a/var/spack/test_repos/requirements.test/packages/gnuconfig
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/gnuconfig
\ No newline at end of file
diff --git a/var/spack/test_repos/requirements.test/packages/llvm b/var/spack/test_repos/requirements.test/packages/llvm
deleted file mode 120000
index 7dddef3a960..00000000000
--- a/var/spack/test_repos/requirements.test/packages/llvm
+++ /dev/null
@@ -1 +0,0 @@
-../../builtin.mock/packages/llvm
\ No newline at end of file
diff --git a/var/spack/test_repos/requirements.test/repo.yaml b/var/spack/test_repos/requirements.test/repo.yaml
deleted file mode 100644
index 7be2a780ea7..00000000000
--- a/var/spack/test_repos/requirements.test/repo.yaml
+++ /dev/null
@@ -1,2 +0,0 @@
-repo:
-  namespace: requirements.test
diff --git a/var/spack/test_repos/builder.test/packages/builder-and-mixins/package.py b/var/spack/test_repos/spack_repo/builder_test/packages/builder_and_mixins/package.py
similarity index 100%
rename from var/spack/test_repos/builder.test/packages/builder-and-mixins/package.py
rename to var/spack/test_repos/spack_repo/builder_test/packages/builder_and_mixins/package.py
diff --git a/var/spack/test_repos/builder.test/packages/callbacks/package.py b/var/spack/test_repos/spack_repo/builder_test/packages/callbacks/package.py
similarity index 100%
rename from var/spack/test_repos/builder.test/packages/callbacks/package.py
rename to var/spack/test_repos/spack_repo/builder_test/packages/callbacks/package.py
diff --git a/var/spack/test_repos/builder.test/packages/custom-phases/package.py b/var/spack/test_repos/spack_repo/builder_test/packages/custom_phases/package.py
similarity index 100%
rename from var/spack/test_repos/builder.test/packages/custom-phases/package.py
rename to var/spack/test_repos/spack_repo/builder_test/packages/custom_phases/package.py
diff --git a/var/spack/test_repos/builder.test/packages/gmake/package.py b/var/spack/test_repos/spack_repo/builder_test/packages/gmake/package.py
similarity index 100%
rename from var/spack/test_repos/builder.test/packages/gmake/package.py
rename to var/spack/test_repos/spack_repo/builder_test/packages/gmake/package.py
diff --git a/var/spack/test_repos/builder.test/packages/gnuconfig/package.py b/var/spack/test_repos/spack_repo/builder_test/packages/gnuconfig/package.py
similarity index 100%
rename from var/spack/test_repos/builder.test/packages/gnuconfig/package.py
rename to var/spack/test_repos/spack_repo/builder_test/packages/gnuconfig/package.py
diff --git a/var/spack/test_repos/builder.test/packages/inheritance/package.py b/var/spack/test_repos/spack_repo/builder_test/packages/inheritance/package.py
similarity index 78%
rename from var/spack/test_repos/builder.test/packages/inheritance/package.py
rename to var/spack/test_repos/spack_repo/builder_test/packages/inheritance/package.py
index b1181d6e834..ab3940d7e76 100644
--- a/var/spack/test_repos/builder.test/packages/inheritance/package.py
+++ b/var/spack/test_repos/spack_repo/builder_test/packages/inheritance/package.py
@@ -3,17 +3,17 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 import os
 
-import spack.pkg.builder.test.callbacks
+import spack.pkg.builder_test.callbacks
 from spack.package import *
 
 
-class Inheritance(spack.pkg.builder.test.callbacks.Callbacks):
+class Inheritance(spack.pkg.builder_test.callbacks.Callbacks):
     """Package used to verify that inheritance among packages work as expected"""
 
     pass
 
 
-class GenericBuilder(spack.pkg.builder.test.callbacks.GenericBuilder):
+class GenericBuilder(spack.pkg.builder_test.callbacks.GenericBuilder):
     def install(self, pkg, spec, prefix):
         super().install(pkg, spec, prefix)
         os.environ["INHERITANCE_INSTALL_CALLED"] = "1"
diff --git a/var/spack/test_repos/builder.test/packages/old-style-autotools/package.py b/var/spack/test_repos/spack_repo/builder_test/packages/old_style_autotools/package.py
similarity index 100%
rename from var/spack/test_repos/builder.test/packages/old-style-autotools/package.py
rename to var/spack/test_repos/spack_repo/builder_test/packages/old_style_autotools/package.py
diff --git a/var/spack/test_repos/builder.test/packages/old-style-custom-phases/package.py b/var/spack/test_repos/spack_repo/builder_test/packages/old_style_custom_phases/package.py
similarity index 100%
rename from var/spack/test_repos/builder.test/packages/old-style-custom-phases/package.py
rename to var/spack/test_repos/spack_repo/builder_test/packages/old_style_custom_phases/package.py
diff --git a/var/spack/test_repos/builder.test/packages/old-style-derived/package.py b/var/spack/test_repos/spack_repo/builder_test/packages/old_style_derived/package.py
similarity index 83%
rename from var/spack/test_repos/builder.test/packages/old-style-derived/package.py
rename to var/spack/test_repos/spack_repo/builder_test/packages/old_style_derived/package.py
index 08e9accf584..0eefa470c9a 100644
--- a/var/spack/test_repos/builder.test/packages/old-style-derived/package.py
+++ b/var/spack/test_repos/spack_repo/builder_test/packages/old_style_derived/package.py
@@ -1,11 +1,11 @@
 # Copyright Spack Project Developers. See COPYRIGHT file for details.
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
-import spack.pkg.builder.test.old_style_autotools
+import spack.pkg.builder_test.old_style_autotools
 from spack.package import *
 
 
-class OldStyleDerived(spack.pkg.builder.test.old_style_autotools.OldStyleAutotools):
+class OldStyleDerived(spack.pkg.builder_test.old_style_autotools.OldStyleAutotools):
     """Package used to verify that old-style packages work correctly when executing the
     installation procedure.
     """
diff --git a/var/spack/test_repos/spack_repo/builder_test/repo.yaml b/var/spack/test_repos/spack_repo/builder_test/repo.yaml
new file mode 100644
index 00000000000..5b64d8f2e59
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/builder_test/repo.yaml
@@ -0,0 +1,3 @@
+repo:
+  namespace: builder_test
+  api: v2.0
diff --git a/var/spack/test_repos/builtin.mock/packages/7zip/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/_7zip/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/7zip/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/_7zip/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/adios2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/adios2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/adios2/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/adios2/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/archive-files/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/archive_files/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/archive-files/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/archive_files/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/ascent/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/ascent/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/ascent/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/ascent/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/attributes-foo/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/attributes_foo/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/attributes-foo/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/attributes_foo/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/attributes-foo-app/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/attributes_foo_app/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/attributes-foo-app/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/attributes_foo_app/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/autotools-conditional-variants-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/autotools_conditional_variants_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/autotools-conditional-variants-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/autotools_conditional_variants_test/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/autotools-config-replacement/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/autotools_config_replacement/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/autotools-config-replacement/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/autotools_config_replacement/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/boost/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/boost/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/boost/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/boost/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/both-link-and-build-dep-a/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/both_link_and_build_dep_a/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/both-link-and-build-dep-a/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/both_link_and_build_dep_a/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/both-link-and-build-dep-b/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/both_link_and_build_dep_b/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/both-link-and-build-dep-b/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/both_link_and_build_dep_b/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/both-link-and-build-dep-c/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/both_link_and_build_dep_c/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/both-link-and-build-dep-c/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/both_link_and_build_dep_c/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/bowtie/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/bowtie/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/bowtie/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/bowtie/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/brillig/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/brillig/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/brillig/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/brillig/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/build-env-compiler-var-a/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/build_env_compiler_var_a/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/build-env-compiler-var-a/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/build_env_compiler_var_a/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/build-env-compiler-var-b/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/build_env_compiler_var_b/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/build-env-compiler-var-b/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/build_env_compiler_var_b/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/build-error/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/build_error/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/build-error/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/build_error/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/build-warnings/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/build_warnings/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/build-warnings/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/build_warnings/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/bzip2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/bzip2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/bzip2/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/bzip2/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/callpath/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/callpath/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/callpath/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/callpath/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/canfail/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/canfail/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/canfail/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/canfail/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/client-not-foo/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/client_not_foo/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/client-not-foo/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/client_not_foo/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/cmake/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/cmake/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/cmake/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/cmake/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/cmake-client/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/cmake_client/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/cmake-client/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/cmake_client/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/cmake-client-inheritor/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/cmake_client_inheritor/package.py
similarity index 81%
rename from var/spack/test_repos/builtin.mock/packages/cmake-client-inheritor/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/cmake_client_inheritor/package.py
index dd05bb9e000..e53708d9d3b 100644
--- a/var/spack/test_repos/builtin.mock/packages/cmake-client-inheritor/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/cmake_client_inheritor/package.py
@@ -3,7 +3,7 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
 from spack.package import *  # noqa: F401
-from spack.pkg.builtin.mock.cmake_client import CmakeClient
+from ..cmake_client.package import CmakeClient
 
 
 class CmakeClientInheritor(CmakeClient):
diff --git a/var/spack/test_repos/builtin.mock/packages/cmake-conditional-variants-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/cmake_conditional_variants_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/cmake-conditional-variants-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/cmake_conditional_variants_test/package.py
diff --git a/var/spack/test_repos/spack_repo/builtin_mock/packages/compiler_wrapper b/var/spack/test_repos/spack_repo/builtin_mock/packages/compiler_wrapper
new file mode 120000
index 00000000000..4038fc52be2
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/compiler_wrapper
@@ -0,0 +1 @@
+../../../../repos/spack_repo/builtin/packages/compiler_wrapper
\ No newline at end of file
diff --git a/var/spack/test_repos/builtin.mock/packages/conditional-constrained-dependencies/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/conditional_constrained_dependencies/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/conditional-constrained-dependencies/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/conditional_constrained_dependencies/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/conditional-provider/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/conditional_provider/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/conditional-provider/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/conditional_provider/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/conditional-values-in-variant/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/conditional_values_in_variant/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/conditional-values-in-variant/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/conditional_values_in_variant/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/conditional-variant-pkg/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/conditional_variant_pkg/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/conditional-virtual-dependency/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/conditional_virtual_dependency/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/conditionally-extends-direct-dep/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/conditionally_extends_direct_dep/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/conditionally-extends-transitive-dep/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/conditionally_extends_transitive_dep/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/conditionally-patch-dependency/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/conditionally_patch_dependency/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/conditionally-patch-dependency/uuid.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/conditionally_patch_dependency/uuid.patch
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diff --git a/var/spack/test_repos/builtin.mock/packages/configure-warning/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/configure_warning/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/conflict/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/conflict/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/conflicting-dependent/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/conflicting_dependent/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/corge/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/corge/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/cumulative-vrange-bottom/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/cumulative_vrange_bottom/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/cumulative-vrange-middle/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/cumulative_vrange_middle/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/cumulative-vrange-root/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/cumulative_vrange_root/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/cvs-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/cvs_test/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/define-cmake-prefix-paths/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/define_cmake_prefix_paths/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dep-diamond-patch-mid1/mid1.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/dep_diamond_patch_mid1/mid1.patch
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diff --git a/var/spack/test_repos/builtin.mock/packages/dep-diamond-patch-mid1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dep_diamond_patch_mid1/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dep-diamond-patch-mid1/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dep-diamond-patch-mid2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dep_diamond_patch_mid2/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dep-diamond-patch-mid2/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dep-diamond-patch-top/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dep_diamond_patch_top/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dep-diamond-patch-top/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dep-diamond-patch-top/top.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/dep_diamond_patch_top/top.patch
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diff --git a/var/spack/test_repos/builtin.mock/packages/dep-with-variants/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dep_with_variants/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dep-with-variants/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dep-with-variants-if-develop/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dep_with_variants_if_develop/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dep-with-variants-if-develop/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dep-with-variants-if-develop-root/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dep_with_variants_if_develop_root/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dep-with-variants-if-develop-root/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/depb/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/depb/package.py
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rename from var/spack/test_repos/builtin.mock/packages/depb/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dependency-foo-bar/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dependency_foo_bar/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dependency-foo-bar/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dependency-install/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dependency_install/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dependency-install/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dependency-mv/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dependency_mv/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dependency-mv/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dependent-install/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dependent_install/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dependent-install/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dependent-of-dev-build/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dependent_of_dev_build/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dependent-of-dev-build/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/depends-on-define-cmake-prefix-paths/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/depends_on_define_cmake_prefix_paths/package.py
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rename from var/spack/test_repos/builtin.mock/packages/depends-on-define-cmake-prefix-paths/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/depends_on_define_cmake_prefix_paths/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/depends-on-develop/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/depends_on_develop/package.py
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rename from var/spack/test_repos/builtin.mock/packages/depends-on-develop/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/depends-on-manyvariants/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/depends_on_manyvariants/package.py
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rename from var/spack/test_repos/builtin.mock/packages/depends-on-manyvariants/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/depends-on-openmpi/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/depends_on_openmpi/package.py
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rename from var/spack/test_repos/builtin.mock/packages/depends-on-openmpi/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/depends-on-run-env/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/depends_on_run_env/package.py
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rename from var/spack/test_repos/builtin.mock/packages/depends-on-run-env/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/depends-on-virtual-with-abi/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/depends_on_virtual_with_abi/package.py
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rename from var/spack/test_repos/builtin.mock/packages/depends-on-virtual-with-abi/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/deprecated-client/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/deprecated_client/package.py
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rename from var/spack/test_repos/builtin.mock/packages/deprecated-client/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/deprecated-versions/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/deprecated_versions/package.py
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rename from var/spack/test_repos/builtin.mock/packages/deprecated-versions/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dev-build-test-dependent/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dev_build_test_dependent/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dev-build-test-dependent/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dev-build-test-install/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dev_build_test_install/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dev-build-test-install/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dev-build-test-install-phases/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dev_build_test_install_phases/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dev-build-test-install-phases/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/develop-branch-version/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/develop_branch_version/package.py
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rename from var/spack/test_repos/builtin.mock/packages/develop-branch-version/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/develop-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/develop_test/package.py
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rename from var/spack/test_repos/builtin.mock/packages/develop-test/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/develop-test2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/develop_test2/package.py
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rename from var/spack/test_repos/builtin.mock/packages/develop-test2/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/diamond-link-bottom/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/diamond_link_bottom/package.py
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rename from var/spack/test_repos/builtin.mock/packages/diamond-link-bottom/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/diamond-link-left/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/diamond_link_left/package.py
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rename from var/spack/test_repos/builtin.mock/packages/diamond-link-left/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/diamond-link-right/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/diamond_link_right/package.py
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rename from var/spack/test_repos/builtin.mock/packages/diamond-link-right/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/diamond-link-top/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/diamond_link_top/package.py
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rename from var/spack/test_repos/builtin.mock/packages/diamond-link-top/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/diff-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/diff_test/package.py
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rename from var/spack/test_repos/builtin.mock/packages/diff-test/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/direct-dep-foo-bar/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/direct_dep_foo_bar/package.py
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rename from var/spack/test_repos/builtin.mock/packages/direct-dep-foo-bar/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/direct-mpich/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/direct_mpich/package.py
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rename from var/spack/test_repos/builtin.mock/packages/direct-mpich/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dla-future/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dla_future/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dla-future/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dt-diamond/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dt_diamond/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dt-diamond/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dt-diamond-bottom/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dt_diamond_bottom/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dt-diamond-bottom/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dt-diamond-left/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dt_diamond_left/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dt-diamond-left/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dt-diamond-right/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dt_diamond_right/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dt-diamond-right/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dtbuild1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtbuild1/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dtbuild1/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dtbuild2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtbuild2/package.py
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rename from var/spack/test_repos/builtin.mock/packages/dtbuild2/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/dtbuild2/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/dtbuild3/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtbuild3/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dtbuild3/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/dtbuild3/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/dtlink1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtlink1/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dtlink1/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dtlink2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtlink2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dtlink2/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dtlink3/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtlink3/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dtlink3/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dtlink4/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtlink4/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dtlink4/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dtlink5/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtlink5/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dtlink5/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dtrun1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtrun1/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dtrun1/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dtrun2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtrun2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dtrun2/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dtrun3/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtrun3/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dtrun3/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dttop/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dttop/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dttop/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dtuse/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dtuse/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dtuse/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/dyninst/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/dyninst/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/dyninst/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/dyninst/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/ecp-viz-sdk/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/ecp_viz_sdk/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/ecp-viz-sdk/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/extendee/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/extendee/package.py
similarity index 100%
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diff --git a/var/spack/test_repos/builtin.mock/packages/extends-spec/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/extends_spec/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/extends-spec/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/extension1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/extension1/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/extension1/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/extension2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/extension2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/extension2/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/external-buildable-with-variant/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/external_buildable_with_variant/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/external-buildable-with-variant/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/external_buildable_with_variant/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/external-common-gdbm/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/external_common_gdbm/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/external-common-gdbm/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/external_common_gdbm/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/external-common-openssl/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/external_common_openssl/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/external-common-openssl/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/external_common_openssl/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/external-common-perl/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/external_common_perl/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/external-common-perl/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/external_common_perl/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/external-common-python/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/external_common_python/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/external-common-python/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/external_common_python/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/external-non-default-variant/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/external_non_default_variant/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/external-non-default-variant/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/external_non_default_variant/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/externalmodule/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/externalmodule/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/externalmodule/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/externalmodule/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/externalprereq/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/externalprereq/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/externalprereq/package.py
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diff --git a/var/spack/test_repos/builtin.mock/packages/externaltest/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/externaltest/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/externaltest/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/externaltest/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/externaltool/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/externaltool/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/externaltool/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/externaltool/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/externalvirtual/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/externalvirtual/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/externalvirtual/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/externalvirtual/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/fail-test-audit/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/fail_test_audit/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/fail-test-audit/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/fail_test_audit/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/fail-test-audit-deprecated/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/fail_test_audit_deprecated/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/fail-test-audit-deprecated/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/fail_test_audit_deprecated/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/fail-test-audit-docstring/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/fail_test_audit_docstring/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/fail-test-audit-docstring/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/fail_test_audit_docstring/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/fail-test-audit-impl/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/fail_test_audit_impl/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/fail-test-audit-impl/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/fail_test_audit_impl/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/failing-build/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/failing_build/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/failing-build/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/failing_build/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/failing-empty-install/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/failing_empty_install/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/failing-empty-install/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/failing_empty_install/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/fake/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/fake/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/fake/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/fake/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/fetch-options/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/fetch_options/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/fetch-options/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/fetch_options/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/fftw/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/fftw/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/fftw/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/fftw/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/find-externals1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/find_externals1/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/find-externals1/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/find_externals1/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/flake8/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/flake8/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/flake8/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/flake8/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/forward-multi-value/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/forward_multi_value/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/forward-multi-value/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/forward_multi_value/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/garply/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/garply/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/garply/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/garply/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/gcc/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/gcc/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/gcc/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/gcc/package.py
diff --git a/var/spack/test_repos/spack_repo/builtin_mock/packages/gcc_runtime b/var/spack/test_repos/spack_repo/builtin_mock/packages/gcc_runtime
new file mode 120000
index 00000000000..e0adc28335e
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/gcc_runtime
@@ -0,0 +1 @@
+../../../../repos/spack_repo/builtin/packages/gcc_runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/builtin.mock/packages/git-ref-package/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/git_ref_package/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/git-ref-package/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/git_ref_package/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/git-sparsepaths-pkg/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/git_sparsepaths_pkg/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/git-sparsepaths-pkg/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/git_sparsepaths_pkg/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/git-svn-top-level/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/git_svn_top_level/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/git-svn-top-level/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/git_svn_top_level/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/git-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/git_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/git-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/git_test/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/git-test-commit/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/git_test_commit/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/git-test-commit/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/git_test_commit/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/git-top-level/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/git_top_level/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/git-top-level/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/git_top_level/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/git-url-svn-top-level/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/git_url_svn_top_level/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/git-url-svn-top-level/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/git_url_svn_top_level/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/git-url-top-level/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/git_url_top_level/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/git-url-top-level/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/git_url_top_level/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/glibc/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/glibc/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/glibc/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/glibc/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/gmake/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/gmake/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/gmake/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/gmake/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/gmt/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/gmt/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/gmt/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/gmt/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/gmt-concrete-mv-dependency/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/gmt_concrete_mv_dependency/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/gmt-concrete-mv-dependency/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/gmt_concrete_mv_dependency/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/gnuconfig/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/gnuconfig/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/gnuconfig/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/gnuconfig/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/hash-test1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test1/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hash-test1/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test1/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/hash-test1/patch1.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test1/patch1.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hash-test1/patch1.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test1/patch1.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/hash-test1/patch2.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test1/patch2.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hash-test1/patch2.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test1/patch2.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/hash-test2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hash-test2/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test2/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/hash-test2/patch1.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test2/patch1.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hash-test2/patch1.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test2/patch1.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/hash-test3/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test3/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hash-test3/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test3/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/hash-test4/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test4/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hash-test4/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hash_test4/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/hdf5/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/hdf5/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hdf5/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hdf5/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/hg-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/hg_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hg-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hg_test/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/hg-top-level/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/hg_top_level/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hg-top-level/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hg_top_level/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/hpcviewer/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/hpcviewer/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hpcviewer/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hpcviewer/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/hwloc/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/hwloc/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hwloc/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hwloc/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/hypre/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/hypre/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/hypre/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/hypre/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/impossible-concretization/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/impossible_concretization/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/impossible-concretization/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/impossible_concretization/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/indirect-mpich/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/indirect_mpich/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/indirect-mpich/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/indirect_mpich/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/installed-deps-a/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/installed_deps_a/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/installed-deps-a/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/installed_deps_a/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/installed-deps-b/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/installed_deps_b/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/installed-deps-b/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/installed_deps_b/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/installed-deps-c/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/installed_deps_c/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/installed-deps-c/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/installed_deps_c/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/installed-deps-d/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/installed_deps_d/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/installed-deps-d/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/installed_deps_d/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/installed-deps-e/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/installed_deps_e/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/installed-deps-e/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/installed_deps_e/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/intel-oneapi-compilers/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/intel_oneapi_compilers/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/intel-oneapi-compilers/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/intel_oneapi_compilers/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/intel-parallel-studio/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/intel_parallel_studio/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/intel-parallel-studio/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/intel_parallel_studio/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/invalid-github-patch-url/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/invalid_github_patch_url/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/invalid-github-patch-url/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/invalid_github_patch_url/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/invalid-github-pull-commits-patch-url/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/invalid_github_pull_commits_patch_url/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/invalid-github-pull-commits-patch-url/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/invalid_github_pull_commits_patch_url/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/invalid-gitlab-patch-url/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/invalid_gitlab_patch_url/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/invalid-gitlab-patch-url/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/invalid_gitlab_patch_url/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/invalid-selfhosted-gitlab-patch-url/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/invalid_selfhosted_gitlab_patch_url/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/invalid-selfhosted-gitlab-patch-url/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/invalid_selfhosted_gitlab_patch_url/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/leaf-adds-virtual/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/leaf_adds_virtual/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/leaf-adds-virtual/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/leaf_adds_virtual/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/libceed/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/libceed/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/libceed/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/libceed/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/libdwarf/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/libdwarf/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/libdwarf/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/libdwarf/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/libelf/local.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/libelf/local.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/libelf/local.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/libelf/local.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/libelf/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/libelf/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/libelf/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/libelf/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/libtool-deletion/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/libtool_deletion/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/libtool-deletion/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/libtool_deletion/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/libtool-installation/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/libtool_installation/package.py
similarity index 70%
rename from var/spack/test_repos/builtin.mock/packages/libtool-installation/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/libtool_installation/package.py
index 7eae15b1f24..981b5d430af 100644
--- a/var/spack/test_repos/builtin.mock/packages/libtool-installation/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/libtool_installation/package.py
@@ -2,8 +2,8 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 from spack.package import *
-from spack.pkg.builtin.mock.libtool_deletion import AutotoolsBuilder as BuilderBase
-from spack.pkg.builtin.mock.libtool_deletion import LibtoolDeletion
+from ..libtool_deletion.package import AutotoolsBuilder as BuilderBase
+from ..libtool_deletion.package import LibtoolDeletion
 
 
 class LibtoolInstallation(LibtoolDeletion, AutotoolsPackage):
diff --git a/var/spack/test_repos/builtin.mock/packages/libxsmm/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/libxsmm/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/libxsmm/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/libxsmm/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/licenses-1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/licenses_1/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/licenses-1/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/licenses_1/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/llvm/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/llvm/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/llvm/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/llvm/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/low-priority-provider/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/low_priority_provider/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/low-priority-provider/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/low_priority_provider/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/maintainers-1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/maintainers_1/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/maintainers-1/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/maintainers_1/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/maintainers-2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/maintainers_2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/maintainers-2/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/maintainers_2/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/maintainers-3/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/maintainers_3/package.py
similarity index 87%
rename from var/spack/test_repos/builtin.mock/packages/maintainers-3/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/maintainers_3/package.py
index 3839b1e5a0f..539b68692d1 100644
--- a/var/spack/test_repos/builtin.mock/packages/maintainers-3/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/maintainers_3/package.py
@@ -2,7 +2,7 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 from spack.package import *
-from spack.pkg.builtin.mock.maintainers_1 import Maintainers1
+from ..maintainers_1.package import Maintainers1
 
 
 class Maintainers3(Maintainers1):
diff --git a/var/spack/test_repos/builtin.mock/packages/many-virtual-consumer/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/many_virtual_consumer/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/many-virtual-consumer/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/many_virtual_consumer/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/manyvariants/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/manyvariants/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/manyvariants/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/manyvariants/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/middle-adds-virtual/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/middle_adds_virtual/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/middle-adds-virtual/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/middle_adds_virtual/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mirror-gnu/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_gnu/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mirror-gnu/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_gnu/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mirror-gnu-broken/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_gnu_broken/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mirror-gnu-broken/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_gnu_broken/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mirror-sourceforge/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_sourceforge/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mirror-sourceforge/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_sourceforge/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mirror-sourceforge-broken/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_sourceforge_broken/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mirror-sourceforge-broken/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_sourceforge_broken/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mirror-sourceware/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_sourceware/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mirror-sourceware/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_sourceware/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mirror-sourceware-broken/mirror-gnu-broken/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_sourceware_broken/mirror-gnu-broken/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mirror-sourceware-broken/mirror-gnu-broken/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_sourceware_broken/mirror-gnu-broken/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mirror-sourceware-broken/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_sourceware_broken/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mirror-sourceware-broken/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_sourceware_broken/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mirror-xorg/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_xorg/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mirror-xorg/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_xorg/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mirror-xorg-broken/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_xorg_broken/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mirror-xorg-broken/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mirror_xorg_broken/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/missing-dependency/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/missing_dependency/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/missing-dependency/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/missing_dependency/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mixedversions/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mixedversions/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mixedversions/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mixedversions/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/modifies-run-env/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/modifies_run_env/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/modifies-run-env/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/modifies_run_env/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/module-long-help/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/module_long_help/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/module-long-help/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/module_long_help/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/module-manpath-append/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/module_manpath_append/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/module-manpath-append/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/module_manpath_append/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/module-manpath-prepend/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/module_manpath_prepend/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/module-manpath-prepend/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/module_manpath_prepend/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/module-manpath-setenv/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/module_manpath_setenv/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/module-manpath-setenv/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/module_manpath_setenv/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/module-path-separator/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/module_path_separator/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/module-path-separator/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/module_path_separator/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/module-setenv-raw/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/module_setenv_raw/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/module-setenv-raw/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/module_setenv_raw/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mpi/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mpi/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mpi/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mpi/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mpich/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mpich/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mpich/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mpich/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mpich2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mpich2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mpich2/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mpich2/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mpileaks/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mpileaks/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mpileaks/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mpileaks/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/multi-provider-mpi/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/multi_provider_mpi/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/multi-provider-mpi/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/multi_provider_mpi/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/multimethod/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod/package.py
similarity index 98%
rename from var/spack/test_repos/builtin.mock/packages/multimethod/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod/package.py
index 40241739a2a..63be0c03ec1 100644
--- a/var/spack/test_repos/builtin.mock/packages/multimethod/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod/package.py
@@ -4,7 +4,7 @@
 
 import spack.platforms
 from spack.package import *
-from spack.pkg.builtin.mock.multimethod_base import MultimethodBase
+from ..multimethod_base.package import MultimethodBase
 
 
 class Multimethod(MultimethodBase):
diff --git a/var/spack/test_repos/builtin.mock/packages/multimethod-base/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_base/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/multimethod-base/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_base/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/multimethod-diamond/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_diamond/package.py
similarity index 64%
rename from var/spack/test_repos/builtin.mock/packages/multimethod-diamond/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_diamond/package.py
index fbc65ada7bb..b38d092ac63 100644
--- a/var/spack/test_repos/builtin.mock/packages/multimethod-diamond/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_diamond/package.py
@@ -2,12 +2,12 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
-import spack.pkg.builtin.mock.multimethod_diamond_parent as mp
-import spack.pkg.builtin.mock.multimethod_inheritor as mi
+from ..multimethod_diamond_parent.package import MultimethodDiamondParent
+from ..multimethod_inheritor.package import MultimethodInheritor
 from spack.package import *
 
 
-class MultimethodDiamond(mi.MultimethodInheritor, mp.MultimethodDiamondParent):
+class MultimethodDiamond(MultimethodInheritor, MultimethodDiamondParent):
     """This package is designed for use with Spack's multimethod test.
     It has a bunch of test cases for the @when decorator that the
     test uses.
diff --git a/var/spack/test_repos/builtin.mock/packages/multimethod-diamond-parent/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_diamond_parent/package.py
similarity index 89%
rename from var/spack/test_repos/builtin.mock/packages/multimethod-diamond-parent/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_diamond_parent/package.py
index 91ba49cdf14..1dbebeb2839 100644
--- a/var/spack/test_repos/builtin.mock/packages/multimethod-diamond-parent/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_diamond_parent/package.py
@@ -3,7 +3,7 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
 from spack.package import *
-from spack.pkg.builtin.mock.multimethod_base import MultimethodBase
+from ..multimethod_base.package import MultimethodBase
 
 
 class MultimethodDiamondParent(MultimethodBase):
diff --git a/var/spack/test_repos/builtin.mock/packages/multimethod-inheritor/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_inheritor/package.py
similarity index 90%
rename from var/spack/test_repos/builtin.mock/packages/multimethod-inheritor/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_inheritor/package.py
index de2e69dd259..7bf9d3f73d3 100644
--- a/var/spack/test_repos/builtin.mock/packages/multimethod-inheritor/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimethod_inheritor/package.py
@@ -3,7 +3,7 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
 from spack.package import *
-from spack.pkg.builtin.mock.multimethod import Multimethod
+from ..multimethod.package import Multimethod
 
 
 class MultimethodInheritor(Multimethod):
diff --git a/var/spack/test_repos/builtin.mock/packages/multimodule-inheritance/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimodule_inheritance/package.py
similarity index 89%
rename from var/spack/test_repos/builtin.mock/packages/multimodule-inheritance/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/multimodule_inheritance/package.py
index d7e44a28935..147d7984309 100644
--- a/var/spack/test_repos/builtin.mock/packages/multimodule-inheritance/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/multimodule_inheritance/package.py
@@ -2,7 +2,7 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
-import spack.pkg.builtin.mock.simple_inheritance as si
+import spack.pkg.builtin_mock.simple_inheritance as si
 from spack.package import *
 
 
diff --git a/var/spack/test_repos/builtin.mock/packages/multivalue-variant/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/multivalue_variant/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/multivalue-variant/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/multivalue_variant/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mvapich2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mvapich2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mvapich2/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mvapich2/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/mvdefaults/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/mvdefaults/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/mvdefaults/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/mvdefaults/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/needs-relocation/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/needs_relocation/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/needs-relocation/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/needs_relocation/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/needs-text-relocation/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/needs_text_relocation/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/needs-text-relocation/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/needs_text_relocation/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/netlib-blas/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/netlib_blas/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/netlib-blas/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/netlib_blas/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/netlib-lapack/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/netlib_lapack/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/netlib-lapack/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/netlib_lapack/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/netlib-scalapack/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/netlib_scalapack/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/netlib-scalapack/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/netlib_scalapack/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/ninja/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/ninja/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/ninja/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/ninja/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/no-redistribute/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/no_redistribute/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/no-redistribute/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/no_redistribute/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/no-redistribute-dependent/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/no_redistribute_dependent/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/no-redistribute-dependent/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/no_redistribute_dependent/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/no-url-or-version/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/no_url_or_version/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/no-url-or-version/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/no_url_or_version/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/non-existing-conditional-dep/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/non_existing_conditional_dep/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/non-existing-conditional-dep/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/non_existing_conditional_dep/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/nosource/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/nosource/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/nosource/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/nosource/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/nosource-bundle/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/nosource_bundle/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/nosource-bundle/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/nosource_bundle/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/nosource-install/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/nosource_install/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/nosource-install/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/nosource_install/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/noversion/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/noversion/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/noversion/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/noversion/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/noversion-bundle/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/noversion_bundle/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/noversion-bundle/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/noversion_bundle/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/old-external/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/old_external/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/old-external/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/old_external/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/old-sbang/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/old_sbang/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/old-sbang/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/old_sbang/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/openblas/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/openblas/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/openblas/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/openblas/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/openblas-with-lapack/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/openblas_with_lapack/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/openblas-with-lapack/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/openblas_with_lapack/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/openmpi/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/openmpi/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/openmpi/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/openmpi/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/openssl/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/openssl/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/openssl/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/openssl/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/optional-dep-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/optional_dep_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/optional-dep-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/optional_dep_test/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/optional-dep-test-2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/optional_dep_test_2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/optional-dep-test-2/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/optional_dep_test_2/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/optional-dep-test-3/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/optional_dep_test_3/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/optional-dep-test-3/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/optional_dep_test_3/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/othervirtual/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/othervirtual/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/othervirtual/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/othervirtual/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/override-context-templates/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/override_context_templates/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/override-context-templates/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/override_context_templates/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/override-module-templates/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/override_module_templates/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/override-module-templates/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/override_module_templates/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/parent-foo/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/parent_foo/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/parent-foo/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/parent_foo/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/parent-foo-bar/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/parent_foo_bar/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/parent-foo-bar/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/parent_foo_bar/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/parent-foo-bar-fee/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/parent_foo_bar_fee/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/parent-foo-bar-fee/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/parent_foo_bar_fee/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/patch-several-dependencies/bar.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch/bar.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch-several-dependencies/bar.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch/bar.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/patch-several-dependencies/baz.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch/baz.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch-several-dependencies/baz.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch/baz.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/patch/biz.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch/biz.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch/biz.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch/biz.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/patch-several-dependencies/foo.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch/foo.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch-several-dependencies/foo.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch/foo.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/patch/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/patch-a-dependency/libelf.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch_a_dependency/libelf.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch-a-dependency/libelf.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch_a_dependency/libelf.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/patch-a-dependency/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch_a_dependency/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch-a-dependency/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch_a_dependency/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/patch-inheritance/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch_inheritance/package.py
similarity index 85%
rename from var/spack/test_repos/builtin.mock/packages/patch-inheritance/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch_inheritance/package.py
index 4a41e4a21ad..91aff0659cc 100644
--- a/var/spack/test_repos/builtin.mock/packages/patch-inheritance/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch_inheritance/package.py
@@ -3,7 +3,7 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
 from spack.package import *  # noqa: F401
-from spack.pkg.builtin.mock.patch import Patch
+from ..patch.package import Patch
 
 
 class PatchInheritance(Patch):
diff --git a/var/spack/test_repos/builtin.mock/packages/patch/bar.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch_several_dependencies/bar.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch/bar.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch_several_dependencies/bar.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/patch/baz.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch_several_dependencies/baz.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch/baz.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch_several_dependencies/baz.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/patch/foo.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch_several_dependencies/foo.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch/foo.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch_several_dependencies/foo.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/patch-several-dependencies/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/patch_several_dependencies/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patch-several-dependencies/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patch_several_dependencies/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/patchelf/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/patchelf/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/patchelf/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/patchelf/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/perl/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/perl/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/perl/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/perl/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/perl-extension/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/perl_extension/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/perl-extension/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/perl_extension/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/pkg-a/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/pkg_a/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/pkg-a/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/pkg_a/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/pkg-b/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/pkg_b/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/pkg-b/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/pkg_b/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/pkg-c/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/pkg_c/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/pkg-c/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/pkg_c/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/pkg-e/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/pkg_e/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/pkg-e/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/pkg_e/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/preferred-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/preferred_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/preferred-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/preferred_test/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/printing-package/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/printing_package/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/printing-package/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/printing_package/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/py-extension1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/py_extension1/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/py-extension1/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/py_extension1/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/py-extension2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/py_extension2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/py-extension2/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/py_extension2/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/py-extension3/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/py_extension3/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/py-extension3/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/py_extension3/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/py-pip/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/py_pip/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/py-pip/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/py_pip/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/py-test-callback/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/py_test_callback/package.py
similarity index 96%
rename from var/spack/test_repos/builtin.mock/packages/py-test-callback/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/py_test_callback/package.py
index 1aab343eb7d..cd2f58f2204 100644
--- a/var/spack/test_repos/builtin.mock/packages/py-test-callback/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/py_test_callback/package.py
@@ -3,7 +3,7 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
 import spack.builder
-import spack.pkg.builtin.mock.python as mp
+import spack.pkg.builtin_mock.python as mp
 from spack.build_systems._checks import BuilderWithDefaults, execute_install_time_tests
 from spack.package import *
 
diff --git a/var/spack/test_repos/builtin.mock/packages/py-wheel/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/py_wheel/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/py-wheel/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/py_wheel/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/python/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/python/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/python/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/python/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/python-venv/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/python_venv/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/python-venv/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/python_venv/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/quantum-espresso/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/quantum_espresso/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/quantum-espresso/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/quantum_espresso/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/quux/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/quux/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/quux/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/quux/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/raiser/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/raiser/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/raiser/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/raiser/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/requires_clang/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/requires_clang/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/requires_clang/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/requires_clang/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/requires_clang_or_gcc/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/requires_clang_or_gcc/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/requires_clang_or_gcc/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/requires_clang_or_gcc/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/requires-virtual/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/requires_virtual/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/requires-virtual/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/requires_virtual/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/root/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/root/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/root/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/root/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/root-adds-virtual/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/root_adds_virtual/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/root-adds-virtual/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/root_adds_virtual/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/second-dependency-foo-bar-fee/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/second_dependency_foo_bar_fee/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/second-dependency-foo-bar-fee/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/second_dependency_foo_bar_fee/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/shell-a/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/shell_a/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/shell-a/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/shell_a/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/shell-b/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/shell_b/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/shell-b/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/shell_b/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/simple-inheritance/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/simple_inheritance/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/simple-inheritance/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/simple_inheritance/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/simple-standalone-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/simple_standalone_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/simple-standalone-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/simple_standalone_test/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/singlevalue-variant/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/singlevalue_variant/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/singlevalue-variant/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/singlevalue_variant/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/singlevalue-variant-dependent/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/singlevalue_variant_dependent/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/singlevalue-variant-dependent/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/singlevalue_variant_dependent/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/singlevalue-variant-dependent-type/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/singlevalue_variant_dependent_type/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/singlevalue-variant-dependent-type/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/singlevalue_variant_dependent_type/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/sombrero/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/sombrero/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/sombrero/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/sombrero/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/some-virtual-mv/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/some_virtual_mv/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/some-virtual-mv/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/some_virtual_mv/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/some-virtual-preferred/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/some_virtual_preferred/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/some-virtual-preferred/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/some_virtual_preferred/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/splice-a/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/splice_a/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/splice-a/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/splice_a/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/splice-depends-on-t/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/splice_depends_on_t/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/splice-depends-on-t/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/splice_depends_on_t/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/splice-h/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/splice_h/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/splice-h/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/splice_h/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/splice-t/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/splice_t/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/splice-t/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/splice_t/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/splice-vh/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/splice_vh/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/splice-vh/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/splice_vh/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/splice-vt/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/splice_vt/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/splice-vt/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/splice_vt/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/splice-z/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/splice_z/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/splice-z/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/splice_z/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/sticky-variant/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/sticky_variant/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/sticky-variant/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/sticky_variant/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/sticky-variant-dependent/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/sticky_variant_dependent/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/sticky-variant-dependent/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/sticky_variant_dependent/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/svn-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/svn_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/svn-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/svn_test/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/svn-top-level/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/svn_top_level/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/svn-top-level/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/svn_top_level/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/symly/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/symly/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/symly/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/symly/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/test-build-callbacks/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/test_build_callbacks/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/test-build-callbacks/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/test_build_callbacks/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/test-dep-with-imposed-conditions/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/test_dep_with_imposed_conditions/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/test-dep-with-imposed-conditions/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/test_dep_with_imposed_conditions/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/test-dependency/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/test_dependency/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/test-dependency/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/test_dependency/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/test-error/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/test_error/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/test-error/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/test_error/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/test-fail/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/test_fail/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/test-fail/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/test_fail/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/test-install-callbacks/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/test_install_callbacks/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/test-install-callbacks/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/test_install_callbacks/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/transitive-conditional-virtual-dependency/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/transitive_conditional_virtual_dependency/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/transitive-conditional-virtual-dependency/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/transitive_conditional_virtual_dependency/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/trigger-external-non-default-variant/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/trigger_external_non_default_variant/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/trigger-external-non-default-variant/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/trigger_external_non_default_variant/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/trivial-install-test-package/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/trivial_install_test_package/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/trivial-install-test-package/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/trivial_install_test_package/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/trivial-pkg-with-valid-hash/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/trivial_pkg_with_valid_hash/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/trivial-pkg-with-valid-hash/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/trivial_pkg_with_valid_hash/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/trivial-smoke-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/trivial_smoke_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/trivial-smoke-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/trivial_smoke_test/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/trivial-smoke-test/test/test_file.in b/var/spack/test_repos/spack_repo/builtin_mock/packages/trivial_smoke_test/test/test_file.in
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/trivial-smoke-test/test/test_file.in
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/trivial_smoke_test/test/test_file.in
diff --git a/var/spack/test_repos/builtin.mock/packages/unconstrainable-conflict/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/unconstrainable_conflict/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/unconstrainable-conflict/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/unconstrainable_conflict/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/unsat-provider/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/unsat_provider/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/unsat-provider/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/unsat_provider/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/unsat-virtual-dependency/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/unsat_virtual_dependency/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/unsat-virtual-dependency/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/unsat_virtual_dependency/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/url-list-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/url_list_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/url-list-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/url_list_test/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/url-only-override/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/url_only_override/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/url-only-override/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/url_only_override/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/url-only-override-with-gaps/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/url_only_override_with_gaps/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/url-only-override-with-gaps/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/url_only_override_with_gaps/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/url_override/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/url_override/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/url_override/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/url_override/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/url-test/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/url_test/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/url-test/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/url_test/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/v1-consumer/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/v1_consumer/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/v1-consumer/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/v1_consumer/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/v1-provider/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/v1_provider/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/v1-provider/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/v1_provider/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/variant-on-dependency-condition-a/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/variant_on_dependency_condition_a/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/variant-on-dependency-condition-a/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/variant_on_dependency_condition_a/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/variant-on-dependency-condition-b/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/variant_on_dependency_condition_b/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/variant-on-dependency-condition-b/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/variant_on_dependency_condition_b/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/variant-on-dependency-condition-root/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/variant_on_dependency_condition_root/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/variant-on-dependency-condition-root/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/variant_on_dependency_condition_root/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/variant-values/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/variant_values/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/variant-values/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/variant_values/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/variant-values-override/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/variant_values_override/package.py
similarity index 83%
rename from var/spack/test_repos/builtin.mock/packages/variant-values-override/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/variant_values_override/package.py
index 6ead9cb3f38..b2e3773bb03 100644
--- a/var/spack/test_repos/builtin.mock/packages/variant-values-override/package.py
+++ b/var/spack/test_repos/spack_repo/builtin_mock/packages/variant_values_override/package.py
@@ -2,7 +2,7 @@
 #
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 from spack.package import *
-from spack.pkg.builtin.mock.variant_values import VariantValues
+from ..variant_values.package import VariantValues
 
 
 class VariantValuesOverride(VariantValues):
diff --git a/var/spack/test_repos/builtin.mock/packages/vdefault-or-external/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/vdefault_or_external/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/vdefault-or-external/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/vdefault_or_external/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/vdefault-or-external-root/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/vdefault_or_external_root/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/vdefault-or-external-root/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/vdefault_or_external_root/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/vendorsb/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/vendorsb/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/vendorsb/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/vendorsb/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/version-test-dependency-preferred/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/version_test_dependency_preferred/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/version-test-dependency-preferred/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/version_test_dependency_preferred/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/version-test-pkg/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/version_test_pkg/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/version-test-pkg/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/version_test_pkg/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/version-test-root/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/version_test_root/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/version-test-root/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/version_test_root/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/view-dir/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/view_dir/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/view-dir/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/view_dir/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/view-file/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/view_file/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/view-file/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/view_file/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/view-ignore-conflict/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/view_ignore_conflict/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/view-ignore-conflict/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/view_ignore_conflict/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/view-not-ignored/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/view_not_ignored/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/view-not-ignored/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/view_not_ignored/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/view-resolve-conflict-middle/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/view_resolve_conflict_middle/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/view-resolve-conflict-middle/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/view_resolve_conflict_middle/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/view-resolve-conflict-top/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/view_resolve_conflict_top/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/view-resolve-conflict-top/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/view_resolve_conflict_top/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/view-symlinked-dir/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/view_symlinked_dir/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/view-symlinked-dir/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/view_symlinked_dir/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/virtual-abi-1/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/virtual_abi_1/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/virtual-abi-1/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/virtual_abi_1/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/virtual-abi-2/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/virtual_abi_2/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/virtual-abi-2/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/virtual_abi_2/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/virtual-abi-multi/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/virtual_abi_multi/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/virtual-abi-multi/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/virtual_abi_multi/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/virtual-with-abi/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/virtual_with_abi/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/virtual-with-abi/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/virtual_with_abi/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/virtual-with-versions/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/virtual_with_versions/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/virtual-with-versions/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/virtual_with_versions/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/vtk-m/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/vtk_m/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/vtk-m/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/vtk_m/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/when-directives-false/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/when_directives_false/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/when-directives-false/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/when_directives_false/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/when-directives-true/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/when_directives_true/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/when-directives-true/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/when_directives_true/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/with-constraint-met/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/with_constraint_met/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/with-constraint-met/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/with_constraint_met/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/wrong-variant-in-conflicts/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/wrong_variant_in_conflicts/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/wrong-variant-in-conflicts/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/wrong_variant_in_conflicts/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/wrong-variant-in-depends-on/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/wrong_variant_in_depends_on/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/wrong-variant-in-depends-on/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/wrong_variant_in_depends_on/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/zlib/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/zlib/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/zlib/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/zlib/package.py
diff --git a/var/spack/test_repos/builtin.mock/packages/zlib/w_patch.patch b/var/spack/test_repos/spack_repo/builtin_mock/packages/zlib/w_patch.patch
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/zlib/w_patch.patch
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/zlib/w_patch.patch
diff --git a/var/spack/test_repos/builtin.mock/packages/zmpi/package.py b/var/spack/test_repos/spack_repo/builtin_mock/packages/zmpi/package.py
similarity index 100%
rename from var/spack/test_repos/builtin.mock/packages/zmpi/package.py
rename to var/spack/test_repos/spack_repo/builtin_mock/packages/zmpi/package.py
diff --git a/var/spack/test_repos/spack_repo/builtin_mock/repo.yaml b/var/spack/test_repos/spack_repo/builtin_mock/repo.yaml
new file mode 100644
index 00000000000..1b4e482e602
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/builtin_mock/repo.yaml
@@ -0,0 +1,3 @@
+repo:
+  namespace: builtin_mock
+  api: v2.0
diff --git a/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/compiler_wrapper b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/compiler_wrapper
new file mode 120000
index 00000000000..d44fb029f18
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/compiler_wrapper
@@ -0,0 +1 @@
+../../builtin_mock/packages/compiler_wrapper
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gcc b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gcc
new file mode 120000
index 00000000000..9120d4a2882
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gcc
@@ -0,0 +1 @@
+../../builtin_mock/packages/gcc
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gcc_runtime b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gcc_runtime
new file mode 120000
index 00000000000..e55c10af3ea
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gcc_runtime
@@ -0,0 +1 @@
+../../builtin_mock/packages/gcc_runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/glibc b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/glibc
new file mode 120000
index 00000000000..dcc041ca3bd
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/glibc
@@ -0,0 +1 @@
+../../builtin_mock/packages/glibc
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gmake b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gmake
new file mode 120000
index 00000000000..a362851793a
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gmake
@@ -0,0 +1 @@
+../../builtin_mock/packages/gmake
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gnuconfig b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gnuconfig
new file mode 120000
index 00000000000..12f0d0aaeb7
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/gnuconfig
@@ -0,0 +1 @@
+../../builtin_mock/packages/gnuconfig
\ No newline at end of file
diff --git a/var/spack/test_repos/compiler_runtime.test/packages/pkg-a/package.py b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/pkg_a/package.py
similarity index 100%
rename from var/spack/test_repos/compiler_runtime.test/packages/pkg-a/package.py
rename to var/spack/test_repos/spack_repo/compiler_runtime_test/packages/pkg_a/package.py
diff --git a/var/spack/test_repos/compiler_runtime.test/packages/pkg-b/package.py b/var/spack/test_repos/spack_repo/compiler_runtime_test/packages/pkg_b/package.py
similarity index 100%
rename from var/spack/test_repos/compiler_runtime.test/packages/pkg-b/package.py
rename to var/spack/test_repos/spack_repo/compiler_runtime_test/packages/pkg_b/package.py
diff --git a/var/spack/test_repos/spack_repo/compiler_runtime_test/repo.yaml b/var/spack/test_repos/spack_repo/compiler_runtime_test/repo.yaml
new file mode 100644
index 00000000000..999f0f1b71c
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/compiler_runtime_test/repo.yaml
@@ -0,0 +1,3 @@
+repo:
+  namespace: compiler_runtime_test
+  api: v2.0
diff --git a/var/spack/test_repos/spack_repo/duplicates_test/packages/compiler_wrapper b/var/spack/test_repos/spack_repo/duplicates_test/packages/compiler_wrapper
new file mode 120000
index 00000000000..d44fb029f18
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/duplicates_test/packages/compiler_wrapper
@@ -0,0 +1 @@
+../../builtin_mock/packages/compiler_wrapper
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/cycle-a/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/cycle_a/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/cycle-a/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/cycle_a/package.py
diff --git a/var/spack/test_repos/duplicates.test/packages/cycle-b/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/cycle_b/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/cycle-b/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/cycle_b/package.py
diff --git a/var/spack/test_repos/spack_repo/duplicates_test/packages/gcc b/var/spack/test_repos/spack_repo/duplicates_test/packages/gcc
new file mode 120000
index 00000000000..9120d4a2882
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/duplicates_test/packages/gcc
@@ -0,0 +1 @@
+../../builtin_mock/packages/gcc
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/duplicates_test/packages/gcc_runtime b/var/spack/test_repos/spack_repo/duplicates_test/packages/gcc_runtime
new file mode 120000
index 00000000000..e55c10af3ea
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/duplicates_test/packages/gcc_runtime
@@ -0,0 +1 @@
+../../builtin_mock/packages/gcc_runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/duplicates_test/packages/glibc b/var/spack/test_repos/spack_repo/duplicates_test/packages/glibc
new file mode 120000
index 00000000000..dcc041ca3bd
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/duplicates_test/packages/glibc
@@ -0,0 +1 @@
+../../builtin_mock/packages/glibc
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/gmake/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/gmake/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/gmake/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/gmake/package.py
diff --git a/var/spack/test_repos/spack_repo/duplicates_test/packages/gnuconfig b/var/spack/test_repos/spack_repo/duplicates_test/packages/gnuconfig
new file mode 120000
index 00000000000..12f0d0aaeb7
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/duplicates_test/packages/gnuconfig
@@ -0,0 +1 @@
+../../builtin_mock/packages/gnuconfig
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/hdf5/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/hdf5/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/hdf5/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/hdf5/package.py
diff --git a/var/spack/test_repos/spack_repo/duplicates_test/packages/llvm b/var/spack/test_repos/spack_repo/duplicates_test/packages/llvm
new file mode 120000
index 00000000000..97c9d5de63f
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/duplicates_test/packages/llvm
@@ -0,0 +1 @@
+../../builtin_mock/packages/llvm
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/pinned-gmake/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/pinned_gmake/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/pinned-gmake/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/pinned_gmake/package.py
diff --git a/var/spack/test_repos/duplicates.test/packages/pkg-config/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/pkg_config/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/pkg-config/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/pkg_config/package.py
diff --git a/var/spack/test_repos/duplicates.test/packages/py-floating/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/py_floating/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/py-floating/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/py_floating/package.py
diff --git a/var/spack/test_repos/duplicates.test/packages/py-numpy/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/py_numpy/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/py-numpy/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/py_numpy/package.py
diff --git a/var/spack/test_repos/duplicates.test/packages/py-setuptools/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/py_setuptools/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/py-setuptools/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/py_setuptools/package.py
diff --git a/var/spack/test_repos/duplicates.test/packages/py-shapely/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/py_shapely/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/py-shapely/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/py_shapely/package.py
diff --git a/var/spack/test_repos/duplicates.test/packages/python/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/python/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/python/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/python/package.py
diff --git a/var/spack/test_repos/spack_repo/duplicates_test/packages/python_venv b/var/spack/test_repos/spack_repo/duplicates_test/packages/python_venv
new file mode 120000
index 00000000000..4f5a08c4569
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/duplicates_test/packages/python_venv
@@ -0,0 +1 @@
+../../builtin_mock/packages/python_venv
\ No newline at end of file
diff --git a/var/spack/test_repos/duplicates.test/packages/virtual-build/package.py b/var/spack/test_repos/spack_repo/duplicates_test/packages/virtual_build/package.py
similarity index 100%
rename from var/spack/test_repos/duplicates.test/packages/virtual-build/package.py
rename to var/spack/test_repos/spack_repo/duplicates_test/packages/virtual_build/package.py
diff --git a/var/spack/test_repos/spack_repo/duplicates_test/repo.yaml b/var/spack/test_repos/spack_repo/duplicates_test/repo.yaml
new file mode 100644
index 00000000000..3daa9451a99
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/duplicates_test/repo.yaml
@@ -0,0 +1,3 @@
+repo:
+  namespace: duplicates_test
+  api: v2.0
diff --git a/var/spack/test_repos/edges.test/packages/blas-only-client/package.py b/var/spack/test_repos/spack_repo/edges_test/packages/blas_only_client/package.py
similarity index 100%
rename from var/spack/test_repos/edges.test/packages/blas-only-client/package.py
rename to var/spack/test_repos/spack_repo/edges_test/packages/blas_only_client/package.py
diff --git a/var/spack/test_repos/spack_repo/edges_test/packages/compiler_wrapper b/var/spack/test_repos/spack_repo/edges_test/packages/compiler_wrapper
new file mode 120000
index 00000000000..d44fb029f18
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/edges_test/packages/compiler_wrapper
@@ -0,0 +1 @@
+../../builtin_mock/packages/compiler_wrapper
\ No newline at end of file
diff --git a/var/spack/test_repos/edges.test/packages/conditional-edge/package.py b/var/spack/test_repos/spack_repo/edges_test/packages/conditional_edge/package.py
similarity index 100%
rename from var/spack/test_repos/edges.test/packages/conditional-edge/package.py
rename to var/spack/test_repos/spack_repo/edges_test/packages/conditional_edge/package.py
diff --git a/var/spack/test_repos/spack_repo/edges_test/packages/gcc b/var/spack/test_repos/spack_repo/edges_test/packages/gcc
new file mode 120000
index 00000000000..9120d4a2882
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/edges_test/packages/gcc
@@ -0,0 +1 @@
+../../builtin_mock/packages/gcc
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/edges_test/packages/gcc_runtime b/var/spack/test_repos/spack_repo/edges_test/packages/gcc_runtime
new file mode 120000
index 00000000000..e55c10af3ea
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/edges_test/packages/gcc_runtime
@@ -0,0 +1 @@
+../../builtin_mock/packages/gcc_runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/edges_test/packages/glibc b/var/spack/test_repos/spack_repo/edges_test/packages/glibc
new file mode 120000
index 00000000000..dcc041ca3bd
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/edges_test/packages/glibc
@@ -0,0 +1 @@
+../../builtin_mock/packages/glibc
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/edges_test/packages/gmake b/var/spack/test_repos/spack_repo/edges_test/packages/gmake
new file mode 120000
index 00000000000..a362851793a
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/edges_test/packages/gmake
@@ -0,0 +1 @@
+../../builtin_mock/packages/gmake
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/edges_test/packages/gnuconfig b/var/spack/test_repos/spack_repo/edges_test/packages/gnuconfig
new file mode 120000
index 00000000000..12f0d0aaeb7
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/edges_test/packages/gnuconfig
@@ -0,0 +1 @@
+../../builtin_mock/packages/gnuconfig
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/edges_test/packages/llvm b/var/spack/test_repos/spack_repo/edges_test/packages/llvm
new file mode 120000
index 00000000000..97c9d5de63f
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/edges_test/packages/llvm
@@ -0,0 +1 @@
+../../builtin_mock/packages/llvm
\ No newline at end of file
diff --git a/var/spack/test_repos/edges.test/packages/openblas/package.py b/var/spack/test_repos/spack_repo/edges_test/packages/openblas/package.py
similarity index 100%
rename from var/spack/test_repos/edges.test/packages/openblas/package.py
rename to var/spack/test_repos/spack_repo/edges_test/packages/openblas/package.py
diff --git a/var/spack/test_repos/edges.test/packages/zlib/package.py b/var/spack/test_repos/spack_repo/edges_test/packages/zlib/package.py
similarity index 100%
rename from var/spack/test_repos/edges.test/packages/zlib/package.py
rename to var/spack/test_repos/spack_repo/edges_test/packages/zlib/package.py
diff --git a/var/spack/test_repos/spack_repo/edges_test/repo.yaml b/var/spack/test_repos/spack_repo/edges_test/repo.yaml
new file mode 100644
index 00000000000..cfe9dce487b
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/edges_test/repo.yaml
@@ -0,0 +1,3 @@
+repo:
+  namespace: edges_test
+  api: v2.0
diff --git a/var/spack/test_repos/spack_repo/flags_test/packages/compiler_wrapper b/var/spack/test_repos/spack_repo/flags_test/packages/compiler_wrapper
new file mode 120000
index 00000000000..d44fb029f18
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/flags_test/packages/compiler_wrapper
@@ -0,0 +1 @@
+../../builtin_mock/packages/compiler_wrapper
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/flags_test/packages/gcc b/var/spack/test_repos/spack_repo/flags_test/packages/gcc
new file mode 120000
index 00000000000..9120d4a2882
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/flags_test/packages/gcc
@@ -0,0 +1 @@
+../../builtin_mock/packages/gcc
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/flags_test/packages/gcc_runtime b/var/spack/test_repos/spack_repo/flags_test/packages/gcc_runtime
new file mode 120000
index 00000000000..e55c10af3ea
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/flags_test/packages/gcc_runtime
@@ -0,0 +1 @@
+../../builtin_mock/packages/gcc_runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/flags_test/packages/glibc b/var/spack/test_repos/spack_repo/flags_test/packages/glibc
new file mode 120000
index 00000000000..dcc041ca3bd
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/flags_test/packages/glibc
@@ -0,0 +1 @@
+../../builtin_mock/packages/glibc
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/flags_test/packages/gmake b/var/spack/test_repos/spack_repo/flags_test/packages/gmake
new file mode 120000
index 00000000000..e5e280254d7
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/flags_test/packages/gmake
@@ -0,0 +1 @@
+../../builtin_mock/packages/gmake/
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/flags_test/packages/gnuconfig b/var/spack/test_repos/spack_repo/flags_test/packages/gnuconfig
new file mode 120000
index 00000000000..12f0d0aaeb7
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/flags_test/packages/gnuconfig
@@ -0,0 +1 @@
+../../builtin_mock/packages/gnuconfig
\ No newline at end of file
diff --git a/var/spack/test_repos/flags.test/packages/t/package.py b/var/spack/test_repos/spack_repo/flags_test/packages/t/package.py
similarity index 100%
rename from var/spack/test_repos/flags.test/packages/t/package.py
rename to var/spack/test_repos/spack_repo/flags_test/packages/t/package.py
diff --git a/var/spack/test_repos/flags.test/packages/u/package.py b/var/spack/test_repos/spack_repo/flags_test/packages/u/package.py
similarity index 100%
rename from var/spack/test_repos/flags.test/packages/u/package.py
rename to var/spack/test_repos/spack_repo/flags_test/packages/u/package.py
diff --git a/var/spack/test_repos/flags.test/packages/v/package.py b/var/spack/test_repos/spack_repo/flags_test/packages/v/package.py
similarity index 100%
rename from var/spack/test_repos/flags.test/packages/v/package.py
rename to var/spack/test_repos/spack_repo/flags_test/packages/v/package.py
diff --git a/var/spack/test_repos/flags.test/packages/w/package.py b/var/spack/test_repos/spack_repo/flags_test/packages/w/package.py
similarity index 100%
rename from var/spack/test_repos/flags.test/packages/w/package.py
rename to var/spack/test_repos/spack_repo/flags_test/packages/w/package.py
diff --git a/var/spack/test_repos/flags.test/packages/x/package.py b/var/spack/test_repos/spack_repo/flags_test/packages/x/package.py
similarity index 100%
rename from var/spack/test_repos/flags.test/packages/x/package.py
rename to var/spack/test_repos/spack_repo/flags_test/packages/x/package.py
diff --git a/var/spack/test_repos/flags.test/packages/y/package.py b/var/spack/test_repos/spack_repo/flags_test/packages/y/package.py
similarity index 100%
rename from var/spack/test_repos/flags.test/packages/y/package.py
rename to var/spack/test_repos/spack_repo/flags_test/packages/y/package.py
diff --git a/var/spack/test_repos/spack_repo/flags_test/repo.yaml b/var/spack/test_repos/spack_repo/flags_test/repo.yaml
new file mode 100644
index 00000000000..447f7dc59be
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/flags_test/repo.yaml
@@ -0,0 +1,3 @@
+repo:
+  namespace: flags_test
+  api: v2.0
diff --git a/var/spack/test_repos/spack_repo/requirements_test/packages/compiler_wrapper b/var/spack/test_repos/spack_repo/requirements_test/packages/compiler_wrapper
new file mode 120000
index 00000000000..e7ced89cc47
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/requirements_test/packages/compiler_wrapper
@@ -0,0 +1 @@
+../../builtin_mock/packages/compiler_wrapper/
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/requirements_test/packages/gcc b/var/spack/test_repos/spack_repo/requirements_test/packages/gcc
new file mode 120000
index 00000000000..9120d4a2882
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/requirements_test/packages/gcc
@@ -0,0 +1 @@
+../../builtin_mock/packages/gcc
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/requirements_test/packages/gcc_runtime b/var/spack/test_repos/spack_repo/requirements_test/packages/gcc_runtime
new file mode 120000
index 00000000000..e55c10af3ea
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/requirements_test/packages/gcc_runtime
@@ -0,0 +1 @@
+../../builtin_mock/packages/gcc_runtime
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/requirements_test/packages/glibc b/var/spack/test_repos/spack_repo/requirements_test/packages/glibc
new file mode 120000
index 00000000000..dcc041ca3bd
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/requirements_test/packages/glibc
@@ -0,0 +1 @@
+../../builtin_mock/packages/glibc
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/requirements_test/packages/gmake b/var/spack/test_repos/spack_repo/requirements_test/packages/gmake
new file mode 120000
index 00000000000..e5e280254d7
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/requirements_test/packages/gmake
@@ -0,0 +1 @@
+../../builtin_mock/packages/gmake/
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/requirements_test/packages/gnuconfig b/var/spack/test_repos/spack_repo/requirements_test/packages/gnuconfig
new file mode 120000
index 00000000000..12f0d0aaeb7
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/requirements_test/packages/gnuconfig
@@ -0,0 +1 @@
+../../builtin_mock/packages/gnuconfig
\ No newline at end of file
diff --git a/var/spack/test_repos/spack_repo/requirements_test/packages/llvm b/var/spack/test_repos/spack_repo/requirements_test/packages/llvm
new file mode 120000
index 00000000000..97c9d5de63f
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/requirements_test/packages/llvm
@@ -0,0 +1 @@
+../../builtin_mock/packages/llvm
\ No newline at end of file
diff --git a/var/spack/test_repos/requirements.test/packages/t/package.py b/var/spack/test_repos/spack_repo/requirements_test/packages/t/package.py
similarity index 100%
rename from var/spack/test_repos/requirements.test/packages/t/package.py
rename to var/spack/test_repos/spack_repo/requirements_test/packages/t/package.py
diff --git a/var/spack/test_repos/requirements.test/packages/u/package.py b/var/spack/test_repos/spack_repo/requirements_test/packages/u/package.py
similarity index 100%
rename from var/spack/test_repos/requirements.test/packages/u/package.py
rename to var/spack/test_repos/spack_repo/requirements_test/packages/u/package.py
diff --git a/var/spack/test_repos/requirements.test/packages/v/package.py b/var/spack/test_repos/spack_repo/requirements_test/packages/v/package.py
similarity index 100%
rename from var/spack/test_repos/requirements.test/packages/v/package.py
rename to var/spack/test_repos/spack_repo/requirements_test/packages/v/package.py
diff --git a/var/spack/test_repos/requirements.test/packages/x/package.py b/var/spack/test_repos/spack_repo/requirements_test/packages/x/package.py
similarity index 100%
rename from var/spack/test_repos/requirements.test/packages/x/package.py
rename to var/spack/test_repos/spack_repo/requirements_test/packages/x/package.py
diff --git a/var/spack/test_repos/requirements.test/packages/y/package.py b/var/spack/test_repos/spack_repo/requirements_test/packages/y/package.py
similarity index 100%
rename from var/spack/test_repos/requirements.test/packages/y/package.py
rename to var/spack/test_repos/spack_repo/requirements_test/packages/y/package.py
diff --git a/var/spack/test_repos/spack_repo/requirements_test/repo.yaml b/var/spack/test_repos/spack_repo/requirements_test/repo.yaml
new file mode 100644
index 00000000000..8c24bc74d61
--- /dev/null
+++ b/var/spack/test_repos/spack_repo/requirements_test/repo.yaml
@@ -0,0 +1,3 @@
+repo:
+  namespace: requirements_test
+  api: v2.0
diff --git a/var/spack/test_repos/tutorial/packages/armadillo/package.py b/var/spack/test_repos/spack_repo/tutorial/packages/armadillo/package.py
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/armadillo/package.py
rename to var/spack/test_repos/spack_repo/tutorial/packages/armadillo/package.py
diff --git a/var/spack/test_repos/tutorial/packages/armadillo/undef_linux.patch b/var/spack/test_repos/spack_repo/tutorial/packages/armadillo/undef_linux.patch
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/armadillo/undef_linux.patch
rename to var/spack/test_repos/spack_repo/tutorial/packages/armadillo/undef_linux.patch
diff --git a/var/spack/test_repos/tutorial/packages/elpa/package.py b/var/spack/test_repos/spack_repo/tutorial/packages/elpa/package.py
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/elpa/package.py
rename to var/spack/test_repos/spack_repo/tutorial/packages/elpa/package.py
diff --git a/var/spack/test_repos/tutorial/packages/hdf5/h5f90global-mult-obj-same-equivalence-same-common-block.patch b/var/spack/test_repos/spack_repo/tutorial/packages/hdf5/h5f90global-mult-obj-same-equivalence-same-common-block.patch
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/hdf5/h5f90global-mult-obj-same-equivalence-same-common-block.patch
rename to var/spack/test_repos/spack_repo/tutorial/packages/hdf5/h5f90global-mult-obj-same-equivalence-same-common-block.patch
diff --git a/var/spack/test_repos/tutorial/packages/hdf5/h5public-skip-mpicxx.patch b/var/spack/test_repos/spack_repo/tutorial/packages/hdf5/h5public-skip-mpicxx.patch
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/hdf5/h5public-skip-mpicxx.patch
rename to var/spack/test_repos/spack_repo/tutorial/packages/hdf5/h5public-skip-mpicxx.patch
diff --git a/var/spack/test_repos/tutorial/packages/hdf5/hdf5_1.8_gcc10.patch b/var/spack/test_repos/spack_repo/tutorial/packages/hdf5/hdf5_1.8_gcc10.patch
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/hdf5/hdf5_1.8_gcc10.patch
rename to var/spack/test_repos/spack_repo/tutorial/packages/hdf5/hdf5_1.8_gcc10.patch
diff --git a/var/spack/test_repos/tutorial/packages/hdf5/package.py b/var/spack/test_repos/spack_repo/tutorial/packages/hdf5/package.py
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/hdf5/package.py
rename to var/spack/test_repos/spack_repo/tutorial/packages/hdf5/package.py
diff --git a/var/spack/test_repos/tutorial/packages/hdf5/pre-c99-comments.patch b/var/spack/test_repos/spack_repo/tutorial/packages/hdf5/pre-c99-comments.patch
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/hdf5/pre-c99-comments.patch
rename to var/spack/test_repos/spack_repo/tutorial/packages/hdf5/pre-c99-comments.patch
diff --git a/var/spack/test_repos/tutorial/packages/hdf5/test/dump.out b/var/spack/test_repos/spack_repo/tutorial/packages/hdf5/test/dump.out
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/hdf5/test/dump.out
rename to var/spack/test_repos/spack_repo/tutorial/packages/hdf5/test/dump.out
diff --git a/var/spack/test_repos/tutorial/packages/hdf5/test/spack.h5 b/var/spack/test_repos/spack_repo/tutorial/packages/hdf5/test/spack.h5
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/hdf5/test/spack.h5
rename to var/spack/test_repos/spack_repo/tutorial/packages/hdf5/test/spack.h5
diff --git a/var/spack/test_repos/tutorial/packages/mpich/mpich32_clang.patch b/var/spack/test_repos/spack_repo/tutorial/packages/mpich/mpich32_clang.patch
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/mpich/mpich32_clang.patch
rename to var/spack/test_repos/spack_repo/tutorial/packages/mpich/mpich32_clang.patch
diff --git a/var/spack/test_repos/tutorial/packages/mpich/package.py b/var/spack/test_repos/spack_repo/tutorial/packages/mpich/package.py
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/mpich/package.py
rename to var/spack/test_repos/spack_repo/tutorial/packages/mpich/package.py
diff --git a/var/spack/test_repos/tutorial/packages/netlib-lapack/ibm-xl.patch b/var/spack/test_repos/spack_repo/tutorial/packages/netlib_lapack/ibm-xl.patch
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/netlib-lapack/ibm-xl.patch
rename to var/spack/test_repos/spack_repo/tutorial/packages/netlib_lapack/ibm-xl.patch
diff --git a/var/spack/test_repos/tutorial/packages/netlib-lapack/package.py b/var/spack/test_repos/spack_repo/tutorial/packages/netlib_lapack/package.py
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/netlib-lapack/package.py
rename to var/spack/test_repos/spack_repo/tutorial/packages/netlib_lapack/package.py
diff --git a/var/spack/test_repos/tutorial/packages/netlib-lapack/testing.patch b/var/spack/test_repos/spack_repo/tutorial/packages/netlib_lapack/testing.patch
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/netlib-lapack/testing.patch
rename to var/spack/test_repos/spack_repo/tutorial/packages/netlib_lapack/testing.patch
diff --git a/var/spack/test_repos/tutorial/packages/netlib-lapack/undefined_declarations.patch b/var/spack/test_repos/spack_repo/tutorial/packages/netlib_lapack/undefined_declarations.patch
similarity index 100%
rename from var/spack/test_repos/tutorial/packages/netlib-lapack/undefined_declarations.patch
rename to var/spack/test_repos/spack_repo/tutorial/packages/netlib_lapack/undefined_declarations.patch
diff --git a/var/spack/test_repos/tutorial/repo.yaml b/var/spack/test_repos/spack_repo/tutorial/repo.yaml
similarity index 70%
rename from var/spack/test_repos/tutorial/repo.yaml
rename to var/spack/test_repos/spack_repo/tutorial/repo.yaml
index b43f5111369..135155eec3f 100644
--- a/var/spack/test_repos/tutorial/repo.yaml
+++ b/var/spack/test_repos/spack_repo/tutorial/repo.yaml
@@ -1,2 +1,3 @@
 repo:
   namespace: tutorial
+  api: v2.0