repo: generalize "swap" context manager to also accept paths

The method is now called "use_repositories" and
makes it clear in the docstring that it accepts
as arguments either Repo objects or paths.

Since there was some duplication between this
contextmanager and "use_repo" in the testing framework,
remove the latter and use spack.repo.use_repositories
across the entire code base.

Make a few adjustment to MockPackageMultiRepo, since it was
stating in the docstring that it was supposed to mock
spack.repo.Repo and was instead mocking spack.repo.RepoPath.

(cherry picked from commit 1a8963b0f4c11c4b7ddd347e6cd95cdc68ddcbe0)

16 files changed, 71 insertions, 61 deletions

diff --git a/lib/spack/spack/repo.py b/lib/spack/spack/repo.py
index 4af7b382f0..52b44e0120 100644
--- a/lib/spack/spack/repo.py
+++ b/lib/spack/spack/repo.py
@@ -1256,23 +1256,6 @@ def set_path(repo):
 
 
 @contextlib.contextmanager
-def swap(repo_path):
-    """Temporarily use another RepoPath."""
-    global path
-
-    # swap out _path for repo_path
-    saved = path
-    remove_from_meta = set_path(repo_path)
-
-    yield
-
-    # restore _path and sys.meta_path
-    if remove_from_meta:
-        sys.meta_path.remove(repo_path)
-    path = saved
-
-
-@contextlib.contextmanager
 def additional_repository(repository):
     """Adds temporarily a repository to the default one.
 
@@ -1284,6 +1267,34 @@ def additional_repository(repository):
     path.remove(repository)
 
 
+@contextlib.contextmanager
+def use_repositories(*paths_and_repos):
+    """Use the repositories passed as arguments within the context manager.
+
+    Args:
+        *paths_and_repos: paths to the repositories to be used, or
+            already constructed Repo objects
+
+    Returns:
+        Corresponding RepoPath object
+    """
+    global path
+
+    # Construct a temporary RepoPath object from
+    temporary_repositories = RepoPath(*paths_and_repos)
+
+    # Swap the current repository out
+    saved = path
+    remove_from_meta = set_path(temporary_repositories)
+
+    yield temporary_repositories
+
+    # Restore _path and sys.meta_path
+    if remove_from_meta:
+        sys.meta_path.remove(temporary_repositories)
+    path = saved
+
+
 class RepoError(spack.error.SpackError):
     """Superclass for repository-related errors."""
 
diff --git a/lib/spack/spack/test/cmd/ci.py b/lib/spack/spack/test/cmd/ci.py
index 4d8468c66c..16af0e99e6 100644
--- a/lib/spack/spack/test/cmd/ci.py
+++ b/lib/spack/spack/test/cmd/ci.py
@@ -73,7 +73,7 @@ and then 'd', 'b', and 'a' to be put in the next three stages, respectively.
     b = mock_repo.add_package('b', [d, e], [default, default])
     mock_repo.add_package('a', [b, c], [default, default])
 
-    with repo.swap(mock_repo):
+    with repo.use_repositories(mock_repo):
         spec_a = Spec('a')
         spec_a.concretize()
 
diff --git a/lib/spack/spack/test/cmd/env.py b/lib/spack/spack/test/cmd/env.py
index c2d75d9d1f..72f1b86347 100644
--- a/lib/spack/spack/test/cmd/env.py
+++ b/lib/spack/spack/test/cmd/env.py
@@ -330,7 +330,7 @@ def test_env_status_broken_view(
         # switch to a new repo that doesn't include the installed package
         # test that Spack detects the missing package and warns the user
         new_repo = MockPackageMultiRepo()
-        with spack.repo.swap(new_repo):
+        with spack.repo.use_repositories(new_repo):
             output = env('status')
             assert 'In environment test' in output
             assert 'Environment test includes out of date' in output
@@ -351,7 +351,7 @@ def test_env_activate_broken_view(
     # switch to a new repo that doesn't include the installed package
     # test that Spack detects the missing package and fails gracefully
     new_repo = MockPackageMultiRepo()
-    with spack.repo.swap(new_repo):
+    with spack.repo.use_repositories(new_repo):
         with pytest.raises(SpackCommandError):
             env('activate', '--sh', 'test')
 
@@ -929,7 +929,7 @@ def test_read_old_lock_and_write_new(tmpdir):
     y = mock_repo.add_package('y', [], [])
     mock_repo.add_package('x', [y], [build_only])
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         x = Spec('x')
         x.concretize()
 
@@ -960,7 +960,7 @@ def test_read_old_lock_creates_backup(tmpdir):
     mock_repo = MockPackageMultiRepo()
     y = mock_repo.add_package('y', [], [])
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         y = Spec('y')
         y.concretize()
 
@@ -997,7 +997,7 @@ def test_indirect_build_dep():
         pass
     setattr(mock_repo, 'dump_provenance', noop)
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         x_spec = Spec('x')
         x_concretized = x_spec.concretized()
 
@@ -1038,7 +1038,7 @@ def test_store_different_build_deps():
         pass
     setattr(mock_repo, 'dump_provenance', noop)
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         y_spec = Spec('y ^z@3')
         y_concretized = y_spec.concretized()
 
diff --git a/lib/spack/spack/test/cmd/module.py b/lib/spack/spack/test/cmd/module.py
index c3fe279306..9a34368fce 100644
--- a/lib/spack/spack/test/cmd/module.py
+++ b/lib/spack/spack/test/cmd/module.py
@@ -10,7 +10,7 @@ import pytest
 
 import spack.main
 import spack.modules
-from spack.test.conftest import use_store, use_configuration, use_repo
+from spack.test.conftest import use_store, use_configuration
 
 module = spack.main.SpackCommand('module')
 
@@ -23,7 +23,7 @@ def ensure_module_files_are_there(
     module = spack.main.SpackCommand('module')
     with use_store(mock_store):
         with use_configuration(mock_configuration):
-            with use_repo(mock_repo_path):
+            with spack.repo.use_repositories(mock_repo_path):
                 module('tcl', 'refresh', '-y')
 
 
diff --git a/lib/spack/spack/test/cmd/pkg.py b/lib/spack/spack/test/cmd/pkg.py
index ca9e3a1a3e..52127e8605 100644
--- a/lib/spack/spack/test/cmd/pkg.py
+++ b/lib/spack/spack/test/cmd/pkg.py
@@ -82,7 +82,7 @@ def mock_pkg_git_repo(tmpdir_factory):
         git('-c', 'commit.gpgsign=false', 'commit',
             '-m', 'change pkg-b, remove pkg-c, add pkg-d')
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         yield mock_repo_packages
 
 
diff --git a/lib/spack/spack/test/concretize.py b/lib/spack/spack/test/concretize.py
index a54a65970f..e5eaa7b7fb 100644
--- a/lib/spack/spack/test/concretize.py
+++ b/lib/spack/spack/test/concretize.py
@@ -304,7 +304,7 @@ class TestConcretize(object):
         barpkg = mock_repo.add_package('barpkg', [bazpkg], [default_dep])
         mock_repo.add_package('foopkg', [barpkg], [default_dep])
 
-        with spack.repo.swap(mock_repo):
+        with spack.repo.use_repositories(mock_repo):
             spec = Spec('foopkg %gcc@4.5.0 os=CNL target=nocona' +
                         ' ^barpkg os=SuSE11 ^bazpkg os=be')
             spec.concretize()
diff --git a/lib/spack/spack/test/conftest.py b/lib/spack/spack/test/conftest.py
index d4f38f2c1b..f214c78c18 100644
--- a/lib/spack/spack/test/conftest.py
+++ b/lib/spack/spack/test/conftest.py
@@ -382,19 +382,12 @@ def use_store(store):
     spack.store.store = saved
 
 
-@contextlib.contextmanager
-def use_repo(repo):
-    """Context manager to swap out the global Spack repo path."""
-    with spack.repo.swap(repo):
-        yield
-
-
 #
 # Test-specific fixtures
 #
 @pytest.fixture(scope='session')
 def mock_repo_path():
-    yield spack.repo.RepoPath(spack.paths.mock_packages_path)
+    yield spack.repo.Repo(spack.paths.mock_packages_path)
 
 
 def _pkg_install_fn(pkg, spec, prefix):
@@ -411,15 +404,15 @@ def mock_pkg_install(monkeypatch):
 @pytest.fixture(scope='function')
 def mock_packages(mock_repo_path, mock_pkg_install):
     """Use the 'builtin.mock' repository instead of 'builtin'"""
-    with use_repo(mock_repo_path):
-        yield mock_repo_path
+    with spack.repo.use_repositories(mock_repo_path) as mock_repo:
+        yield mock_repo
 
 
 @pytest.fixture(scope='function')
 def mutable_mock_repo(mock_repo_path):
     """Function-scoped mock packages, for tests that need to modify them."""
-    mock_repo_path = spack.repo.RepoPath(spack.paths.mock_packages_path)
-    with use_repo(mock_repo_path):
+    mock_repo = spack.repo.Repo(spack.paths.mock_packages_path)
+    with spack.repo.use_repositories(mock_repo) as mock_repo_path:
         yield mock_repo_path
 
 
@@ -644,7 +637,7 @@ def mock_store(tmpdir_factory, mock_repo_path, mock_configuration,
     if not os.path.exists(str(store_cache.join('.spack-db'))):
         with use_configuration(mock_configuration):
             with use_store(store):
-                with use_repo(mock_repo_path):
+                with spack.repo.use_repositories(mock_repo_path):
                     _populate(store.db)
         store_path.copy(store_cache, mode=True, stat=True)
 
@@ -674,7 +667,7 @@ def mutable_mock_store(tmpdir_factory, mock_repo_path, mock_configuration,
     if not os.path.exists(str(store_cache.join('.spack-db'))):
         with use_configuration(mock_configuration):
             with use_store(store):
-                with use_repo(mock_repo_path):
+                with spack.repo.use_repositories(mock_repo_path):
                     _populate(store.db)
         store_path.copy(store_cache, mode=True, stat=True)
 
@@ -1250,8 +1243,7 @@ repo:
     namespace: mock_test_repo
 """)
 
-    repo = spack.repo.RepoPath(str(repodir))
-    with spack.repo.swap(repo):
+    with spack.repo.use_repositories(str(repodir)) as repo:
         yield repo, repodir
 
     shutil.rmtree(str(repodir))
diff --git a/lib/spack/spack/test/database.py b/lib/spack/spack/test/database.py
index 4682c9850d..8e0eac7cc0 100644
--- a/lib/spack/spack/test/database.py
+++ b/lib/spack/spack/test/database.py
@@ -81,7 +81,7 @@ def test_installed_upstream(upstream_and_downstream_db):
     y = mock_repo.add_package('y', [z], [default])
     mock_repo.add_package('w', [x, y], [default, default])
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         spec = spack.spec.Spec('w')
         spec.concretize()
 
@@ -122,7 +122,7 @@ def test_removed_upstream_dep(upstream_and_downstream_db):
     z = mock_repo.add_package('z', [], [])
     mock_repo.add_package('y', [z], [default])
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         spec = spack.spec.Spec('y')
         spec.concretize()
 
@@ -155,7 +155,7 @@ def test_add_to_upstream_after_downstream(upstream_and_downstream_db):
     mock_repo = MockPackageMultiRepo()
     mock_repo.add_package('x', [], [])
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         spec = spack.spec.Spec('x')
         spec.concretize()
 
@@ -197,7 +197,7 @@ def test_cannot_write_upstream(tmpdir_factory, test_store, gen_mock_layout):
     upstream_dbs = spack.store._construct_upstream_dbs_from_install_roots(
         [roots[1]], _test=True)
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         spec = spack.spec.Spec('x')
         spec.concretize()
 
@@ -216,7 +216,7 @@ def test_recursive_upstream_dbs(tmpdir_factory, test_store, gen_mock_layout):
     y = mock_repo.add_package('y', [z], [default])
     mock_repo.add_package('x', [y], [default])
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         spec = spack.spec.Spec('x')
         spec.concretize()
         db_c = spack.database.Database(roots[2])
@@ -694,7 +694,7 @@ def test_115_reindex_with_packages_not_in_repo(mutable_database):
     # Dont add any package definitions to this repository, the idea is that
     # packages should not have to be defined in the repository once they
     # are installed
-    with spack.repo.swap(MockPackageMultiRepo()):
+    with spack.repo.use_repositories(MockPackageMultiRepo()):
         spack.store.store.reindex()
         _check_db_sanity(mutable_database)
 
diff --git a/lib/spack/spack/test/directory_layout.py b/lib/spack/spack/test/directory_layout.py
index 3a144621eb..3cb976a077 100644
--- a/lib/spack/spack/test/directory_layout.py
+++ b/lib/spack/spack/test/directory_layout.py
@@ -194,7 +194,7 @@ def test_handle_unknown_package(layout_and_dir, config, mock_packages):
         layout.create_install_directory(spec)
         installed_specs[spec] = layout.path_for_spec(spec)
 
-    with spack.repo.swap(mock_db):
+    with spack.repo.use_repositories(mock_db):
         # Now check that even without the package files, we know
         # enough to read a spec from the spec file.
         for spec, path in installed_specs.items():
diff --git a/lib/spack/spack/test/installer.py b/lib/spack/spack/test/installer.py
index 3bf818544e..590c4a4a1a 100644
--- a/lib/spack/spack/test/installer.py
+++ b/lib/spack/spack/test/installer.py
@@ -474,14 +474,14 @@ def test_packages_needed_to_bootstrap_compiler_packages(install_mockery,
     assert packages
 
 
-def test_dump_packages_deps_ok(install_mockery, tmpdir, mock_repo_path):
+def test_dump_packages_deps_ok(install_mockery, tmpdir, mock_packages):
     """Test happy path for dump_packages with dependencies."""
 
     spec_name = 'simple-inheritance'
     spec = spack.spec.Spec(spec_name).concretized()
     inst.dump_packages(spec, str(tmpdir))
 
-    repo = mock_repo_path.repos[0]
+    repo = mock_packages.repos[0]
     dest_pkg = repo.filename_for_package_name(spec_name)
     assert os.path.isfile(dest_pkg)
 
diff --git a/lib/spack/spack/test/package_sanity.py b/lib/spack/spack/test/package_sanity.py
index d50169a1a4..ded4d1c485 100644
--- a/lib/spack/spack/test/package_sanity.py
+++ b/lib/spack/spack/test/package_sanity.py
@@ -73,7 +73,7 @@ def test_repo_getpkg_names_and_classes():
 def test_get_all_mock_packages():
     """Get the mock packages once each too."""
     db = spack.repo.RepoPath(spack.paths.mock_packages_path)
-    with spack.repo.swap(db):
+    with spack.repo.use_repositories(db):
         check_repo()
 
 
diff --git a/lib/spack/spack/test/spec_dag.py b/lib/spack/spack/test/spec_dag.py
index 2ac5bec4d9..854495988b 100644
--- a/lib/spack/spack/test/spec_dag.py
+++ b/lib/spack/spack/test/spec_dag.py
@@ -75,7 +75,7 @@ w->y deptypes are (link, build), w->x and y->z deptypes are (test)
     y = mock_repo.add_package('y', [z], [test_only])
     w = mock_repo.add_package('w', [x, y], [test_only, default])
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         spec = Spec('w')
         spec.concretize(tests=(w.name,))
 
@@ -114,7 +114,7 @@ def test_installed_deps():
     b = mock_repo.add_package('b', [d, e], [default, default])
     mock_repo.add_package('a', [b, c], [default, default])
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         c_spec = Spec('c')
         c_spec.concretize()
         assert c_spec['d'].version == spack.version.Version('2')
@@ -143,7 +143,7 @@ def test_specify_preinstalled_dep():
     b = mock_repo.add_package('b', [c], [default])
     mock_repo.add_package('a', [b], [default])
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         b_spec = Spec('b')
         b_spec.concretize()
         for spec in b_spec.traverse():
@@ -186,7 +186,7 @@ def test_conditional_dep_with_user_constraints(spec_str, expr_str, expected):
     }
     mock_repo.add_package('x', [y], [default], conditions=x_on_y_conditions)
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         spec = Spec(spec_str)
         spec.concretize()
 
diff --git a/lib/spack/spack/test/spec_yaml.py b/lib/spack/spack/test/spec_yaml.py
index 12a3982f06..b32fe09e03 100644
--- a/lib/spack/spack/test/spec_yaml.py
+++ b/lib/spack/spack/test/spec_yaml.py
@@ -315,7 +315,7 @@ def test_save_dependency_spec_yamls_subset(tmpdir, config):
     b = mock_repo.add_package('b', [d, e], [default, default])
     mock_repo.add_package('a', [b, c], [default, default])
 
-    with repo.swap(mock_repo):
+    with repo.use_repositories(mock_repo):
         spec_a = Spec('a')
         spec_a.concretize()
         b_spec = spec_a['b']
diff --git a/lib/spack/spack/test/test_activations.py b/lib/spack/spack/test/test_activations.py
index d1780b8963..e8ce6c55ed 100644
--- a/lib/spack/spack/test/test_activations.py
+++ b/lib/spack/spack/test/test_activations.py
@@ -54,7 +54,7 @@ def builtin_and_mock_packages():
     repo_dirs = [spack.paths.packages_path, spack.paths.mock_packages_path]
     path = RepoPath(*repo_dirs)
 
-    with spack.repo.swap(path):
+    with spack.repo.use_repositories(path):
         yield
 
 
diff --git a/lib/spack/spack/test/util/mock_package.py b/lib/spack/spack/test/util/mock_package.py
index 376ac581bd..cca55bb534 100644
--- a/lib/spack/spack/test/util/mock_package.py
+++ b/lib/spack/spack/test/util/mock_package.py
@@ -15,7 +15,7 @@ def test_mock_package_possible_dependencies():
     b = mock_repo.add_package('b', [d])
     a = mock_repo.add_package('a', [b, c])
 
-    with spack.repo.swap(mock_repo):
+    with spack.repo.use_repositories(mock_repo):
         assert set(a.possible_dependencies()) == set(['a', 'b', 'c', 'd', 'e'])
         assert set(b.possible_dependencies()) == set(['b', 'd', 'e'])
         assert set(c.possible_dependencies()) == set(['c', 'd', 'e'])
diff --git a/lib/spack/spack/util/mock_package.py b/lib/spack/spack/util/mock_package.py
index 5286b50464..734a93c469 100644
--- a/lib/spack/spack/util/mock_package.py
+++ b/lib/spack/spack/util/mock_package.py
@@ -8,6 +8,7 @@
 import ordereddict_backport
 
 import spack.util.naming
+import spack.provider_index
 from spack.dependency import Dependency
 from spack.spec import Spec
 from spack.version import Version
@@ -80,6 +81,8 @@ class MockPackageMultiRepo(object):
 
     def __init__(self):
         self.spec_to_pkg = {}
+        self.namespace = ''
+        self.full_namespace = 'spack.pkg.mock'
 
     def get(self, spec):
         if not isinstance(spec, spack.spec.Spec):
@@ -171,3 +174,7 @@ class MockPackageMultiRepo(object):
         self.spec_to_pkg["mockrepo." + name] = mock_package
 
         return mock_package
+
+    @property
+    def provider_index(self):
+        return spack.provider_index.ProviderIndex()