tests: Speed up stdlib tests

tests/test_stdlib.py

@@ -4,10 +4,11 @@
 
 import sys
 from contextlib import suppress
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Iterator
 
 import pytest
 
+from griffe.exceptions import LoadingError
 from griffe.loader import GriffeLoader
 
 if TYPE_CHECKING:
@@ -26,18 +27,24 @@ def _access_inherited_members(obj: Object | Alias) -> None:
             _access_inherited_members(cls)
 
 
-@pytest.mark.skipif(sys.version_info < (3, 10), reason="Python less than 3.10 does not have sys.stdlib_module_names")
-def test_fuzzing_on_stdlib() -> None:
-    """Run Griffe on the standard library."""
-    stblib_packages = sorted([m for m in sys.stdlib_module_names if not m.startswith("_")])  # type: ignore[attr-defined,unused-ignore]
+@pytest.fixture(name="stdlib_loader", scope="session")
+def fixture_stdlib_loader() -> Iterator[GriffeLoader]:
+    """Yield a GriffeLoader instance.
 
-    loader = GriffeLoader()
-    for package in stblib_packages:
-        with suppress(ImportError):
-            loader.load(package)
-
-    loader.resolve_aliases(implicit=True, external=True)
+    During teardown, resolve aliases and access inherited members
+    to make sure that no exception is raised when computing MRO.
+    """
+    loader = GriffeLoader(allow_inspection=False, store_source=False)
+    yield loader
+    loader.resolve_aliases(implicit=True, external=None)
     for module in loader.modules_collection.members.values():
         _access_inherited_members(module)
-
     loader.stats()
+
+
+@pytest.mark.skipif(sys.version_info < (3, 10), reason="Python less than 3.10 does not have sys.stdlib_module_names")
+@pytest.mark.parametrize("mod", sorted([m for m in getattr(sys, "stdlib_module_names", ()) if not m.startswith("_")]))
+def test_fuzzing_on_stdlib(stdlib_loader: GriffeLoader, mod: str) -> None:
+    """Run Griffe on the standard library."""
+    with suppress(ImportError, LoadingError):
+        stdlib_loader.load(mod)