tests: cleanup config:build_stage handling (fixes spack#12651, spack#…

…12798)

lib/spack/spack/config.py

@@ -110,6 +110,9 @@
 #: this is shorter and more readable than listing all choices
 scopes_metavar = '{defaults,system,site,user}[/PLATFORM]'
 
+#: Base name for the (internal) overrides scope.
+overrides_base_name = 'overrides-'
+
 
 def first_existing(dictionary, keys):
     """Get the value of the first key in keys that is in the dictionary."""
@@ -549,11 +552,11 @@ def override(path_or_scope, value=None):
     an internal config scope for it and push/pop that scope.
 
     """
-    base_name = 'overrides-'
     if isinstance(path_or_scope, ConfigScope):
         overrides = path_or_scope
         config.push_scope(path_or_scope)
     else:
+        base_name = overrides_base_name
         # Ensure the new override gets a unique scope name
         current_overrides = [s.name for s in
                              config.matching_scopes(r'^{0}'.format(base_name))]

lib/spack/spack/stage.py

@@ -91,18 +91,29 @@ def _first_accessible_path(paths):
 
 
 def _resolve_paths(candidates):
-    """Resolve paths, removing extra $user from $tempdir if needed."""
+    """
+    Resolve candidate paths and make user-related adjustments.
+
+    Adjustments involve removing extra $user from $tempdir if $tempdir includes
+    $user and appending $user if it is not present in the path.
+    """
     temp_path = sup.canonicalize_path('$tempdir')
-    tmp_has_usr = getpass.getuser() in temp_path.split(os.path.sep)
+    user = getpass.getuser()
+    tmp_has_usr = user in temp_path.split(os.path.sep)
 
     paths = []
     for path in candidates:
-        # First remove the extra `$user` node from a `$tempdir/$user` entry
-        # for hosts that automatically append `$user` to `$tempdir`.
+        # Remove the extra `$user` node from a `$tempdir/$user` entry for
+        # hosts that automatically append `$user` to `$tempdir`.
         if path.startswith(os.path.join('$tempdir', '$user')) and tmp_has_usr:
             path = os.path.join('$tempdir', path[15:])
 
-        paths.append(sup.canonicalize_path(path))
+        # Ensure the path is unique per user.
+        can_path = sup.canonicalize_path(path)
+        if user not in can_path:
+            can_path = os.path.join(can_path, user)
+
+        paths.append(can_path)
 
     return paths
 
@@ -125,14 +136,6 @@ def get_stage_root():
             raise StageError("No accessible stage paths in:",
                              ' '.join(resolved_candidates))
 
-        # Ensure that path is unique per user in an attempt to avoid
-        # conflicts in shared temporary spaces.  Emulate permissions from
-        # `tempfile.mkdtemp`.
-        user = getpass.getuser()
-        if user not in path:
-            path = os.path.join(path, user)
-            mkdirp(path, mode=stat.S_IRWXU)
-
         _stage_root = path
 
     return _stage_root

lib/spack/spack/test/config.py

@@ -627,14 +627,13 @@ def test_add_command_line_scopes(tmpdir, mutable_config):
     spack.config._add_command_line_scopes(mutable_config, [str(tmpdir)])
 
 
-@pytest.mark.nomockstage
 def test_nested_override():
     """Ensure proper scope naming of nested overrides."""
-    # WARNING: Base name must match that used in `config.py`s `override()`.
-    base_name = 'overrides-'
+    base_name = spack.config.overrides_base_name
 
     def _check_scopes(num_expected, debug_values):
-        scope_names = [s.name for s in spack.config.config.scopes.values()]
+        scope_names = [s.name for s in spack.config.config.scopes.values() if
+                       s.name.startswith(base_name)]
 
         for i in range(num_expected):
             name = '{0}{1}'.format(base_name, i)
@@ -651,11 +650,9 @@ def _check_scopes(num_expected, debug_values):
         _check_scopes(1, [True])
 
 
-@pytest.mark.nomockstage
 def test_alternate_override(monkeypatch):
     """Ensure proper scope naming of override when conflict present."""
-    # WARNING: Base name must match that used in `config.py`s `override()`.
-    base_name = 'overrides-'
+    base_name = spack.config.overrides_base_name
 
     def _matching_scopes(regexpr):
         return [spack.config.InternalConfigScope('{0}1'.format(base_name))]

lib/spack/spack/test/conftest.py

@@ -17,7 +17,7 @@
 import pytest
 import ruamel.yaml as yaml
 
-from llnl.util.filesystem import remove_linked_tree
+from llnl.util.filesystem import mkdirp, remove_linked_tree
 
 import spack.architecture
 import spack.compilers
@@ -122,34 +122,27 @@ def reset_compiler_cache():
     spack.compilers._compiler_cache = {}
 
 
-@pytest.fixture
-def clear_stage_root(monkeypatch):
-    """Ensure spack.stage._stage_root is not set at test start."""
-    monkeypatch.setattr(spack.stage, '_stage_root', None)
-    yield
-
-
 @pytest.fixture(scope='function', autouse=True)
-def mock_stage(clear_stage_root, tmpdir_factory, request):
+def mock_stage(tmpdir_factory, monkeypatch, request):
     """Establish the temporary build_stage for the mock archive."""
-    # Workaround to skip mock_stage for 'nomockstage' test cases
+    # The approach with this autouse fixture is to set the stage root
+    # instead of using spack.config.override() to avoid configuration
+    # conflicts with dozens of tests that rely on other configuration
+    # fixtures, such as config.
     if 'nomockstage' not in request.keywords:
+        # Set the build stage to the requested path
         new_stage = tmpdir_factory.mktemp('mock-stage')
         new_stage_path = str(new_stage)
 
-        # Set test_stage_path as the default directory to use for test stages.
-        current = spack.config.get('config:build_stage')
-        spack.config.set('config',
-                         {'build_stage': new_stage_path}, scope='user')
+        # Ensure the source directory exists within the new stage path
+        source_path = os.path.join(new_stage_path,
+                                   spack.stage._source_path_subdir)
+        mkdirp(source_path)
 
-        # Ensure the source directory exists
-        source_path = new_stage.join(spack.stage._source_path_subdir)
-        source_path.ensure(dir=True)
+        monkeypatch.setattr(spack.stage, '_stage_root', new_stage_path)
 
         yield new_stage_path
 
-        spack.config.set('config', {'build_stage': current}, scope='user')
-
         # Clean up the test stage directory
         if os.path.isdir(new_stage_path):
             shutil.rmtree(new_stage_path)