Improve performance by caching find_spec

astroid/interpreter/_import/spec.py

@@ -16,6 +16,7 @@
 import warnings
 import zipimport
 from collections.abc import Iterator, Sequence
+from functools import lru_cache
 from pathlib import Path
 from typing import Any, Literal, NamedTuple, Protocol
 
@@ -440,10 +441,15 @@ def find_spec(modpath: list[str], path: Sequence[str] | None = None) -> ModuleSp
     :return: A module spec, which describes how the module was
              found and where.
     """
+    return _find_spec(tuple(modpath), tuple(path) if path else None)
+
+
+@lru_cache(maxsize=1024)
+def _find_spec(modpath: tuple, path: tuple) -> ModuleSpec:
     _path = path or sys.path
 
     # Need a copy for not mutating the argument.
-    modpath = modpath[:]
+    modpath = list(modpath)
 
     submodule_path = None
     module_parts = modpath[:]

astroid/manager.py

@@ -442,6 +442,7 @@ def clear_cache(self) -> None:
         # pylint: disable=import-outside-toplevel
         from astroid.brain.helpers import register_all_brains
         from astroid.inference_tip import clear_inference_tip_cache
+        from astroid.interpreter._import.spec import _find_spec
         from astroid.interpreter.objectmodel import ObjectModel
         from astroid.nodes._base_nodes import LookupMixIn
         from astroid.nodes.scoped_nodes import ClassDef
@@ -459,6 +460,7 @@ def clear_cache(self) -> None:
             util.is_namespace,
             ObjectModel.attributes,
             ClassDef._metaclass_lookup_attribute,
+            _find_spec,
         ):
             lru_cache.cache_clear()  # type: ignore[attr-defined]
 

tests/resources.py

@@ -9,7 +9,6 @@
 from pathlib import Path
 
 from astroid import builder
-from astroid.manager import AstroidManager
 from astroid.nodes.scoped_nodes import Module
 
 DATA_DIR = Path("testdata") / "python3"
@@ -34,28 +33,3 @@ def tearDown(self) -> None:
         for key in list(sys.path_importer_cache):
             if key.startswith(datadir):
                 del sys.path_importer_cache[key]
-
-
-class AstroidCacheSetupMixin:
-    """Mixin for handling test isolation issues with the astroid cache.
-
-    When clearing the astroid cache, some tests fail due to
-    cache inconsistencies, where some objects had a different
-    builtins object referenced.
-    This saves the builtins module and TransformVisitor and
-    replaces them after the tests finish.
-    The builtins module is special, since some of the
-    transforms for a couple of its objects (str, bytes etc)
-    are executed only once, so astroid_bootstrapping will be
-    useless for retrieving the original builtins module.
-    """
-
-    @classmethod
-    def setup_class(cls):
-        cls._builtins = AstroidManager().astroid_cache.get("builtins")
-        cls._transforms = AstroidManager.brain["_transform"]
-
-    @classmethod
-    def teardown_class(cls):
-        AstroidManager().astroid_cache["builtins"] = cls._builtins
-        AstroidManager.brain["_transform"] = cls._transforms

tests/test_manager.py

@@ -36,12 +36,11 @@ def _get_file_from_object(obj) -> str:
     return obj.__file__
 
 
-class AstroidManagerTest(
-    resources.SysPathSetup, resources.AstroidCacheSetupMixin, unittest.TestCase
-):
+class AstroidManagerTest(resources.SysPathSetup, unittest.TestCase):
     def setUp(self) -> None:
         super().setUp()
         self.manager = test_utils.brainless_manager()
+        self.manager.clear_cache()
 
     def test_ast_from_file(self) -> None:
         filepath = unittest.__file__
@@ -391,9 +390,10 @@ def test_denied_modules_raise(self) -> None:
         self.manager.ast_from_module_name("math")
 
 
-class IsolatedAstroidManagerTest(resources.AstroidCacheSetupMixin, unittest.TestCase):
+class IsolatedAstroidManagerTest(unittest.TestCase):
     def test_no_user_warning(self):
         mgr = manager.AstroidManager()
+        self.addCleanup(mgr.clear_cache)
         with warnings.catch_warnings():
             warnings.filterwarnings("error", category=UserWarning)
             mgr.ast_from_module_name("setuptools")

tests/test_modutils.py

@@ -41,6 +41,7 @@ class ModuleFileTest(unittest.TestCase):
     package = "mypypa"
 
     def tearDown(self) -> None:
+        astroid.MANAGER.clear_cache()
         for k in list(sys.path_importer_cache):
             if "MyPyPa" in k:
                 del sys.path_importer_cache[k]

tests/test_regrtest.py

@@ -26,10 +26,11 @@
     HAS_NUMPY = True
 
 
-class NonRegressionTests(resources.AstroidCacheSetupMixin, unittest.TestCase):
+class NonRegressionTests(unittest.TestCase):
     def setUp(self) -> None:
         sys.path.insert(0, resources.find("data"))
         MANAGER.always_load_extensions = True
+        self.addCleanup(MANAGER.clear_cache)
 
     def tearDown(self) -> None:
         MANAGER.always_load_extensions = False