Let AstroidManager.clear_cache act on other caches (#1521)

Co-authored-by: Pierre Sassoulas <[email protected]>

Author: jacobtylerwalls

astroid/inference.py

@@ -23,8 +23,6 @@
     Union,
 )
 
-import wrapt
-
 from astroid import bases, decorators, helpers, nodes, protocols, util
 from astroid.context import (
     CallContext,
@@ -1037,42 +1035,32 @@ def infer_ifexp(self, context=None):
 nodes.IfExp._infer = infer_ifexp  # type: ignore[assignment]
 
 
-# pylint: disable=dangerous-default-value
-@wrapt.decorator
-def _cached_generator(
-    func, instance: _FunctionDefT, args, kwargs, _cache={}  # noqa: B006
-):
-    node = instance
-    try:
-        return iter(_cache[func, id(node)])
-    except KeyError:
-        result = func(*args, **kwargs)
-        # Need to keep an iterator around
-        original, copy = itertools.tee(result)
-        _cache[func, id(node)] = list(copy)
-        return original
-
-
-# When inferring a property, we instantiate a new `objects.Property` object,
-# which in turn, because it inherits from `FunctionDef`, sets itself in the locals
-# of the wrapping frame. This means that every time we infer a property, the locals
-# are mutated with a new instance of the property. This is why we cache the result
-# of the function's inference.
-@_cached_generator
 def infer_functiondef(
     self: _FunctionDefT, context: Optional[InferenceContext] = None
 ) -> Generator[Union["Property", _FunctionDefT], None, InferenceErrorInfo]:
     if not self.decorators or not bases._is_property(self):
         yield self
         return InferenceErrorInfo(node=self, context=context)
 
+    # When inferring a property, we instantiate a new `objects.Property` object,
+    # which in turn, because it inherits from `FunctionDef`, sets itself in the locals
+    # of the wrapping frame. This means that every time we infer a property, the locals
+    # are mutated with a new instance of the property. To avoid this, we detect this
+    # scenario and avoid passing the `parent` argument to the constructor.
+    parent_frame = self.parent.frame(future=True)
+    property_already_in_parent_locals = self.name in parent_frame.locals and any(
+        isinstance(val, objects.Property) for val in parent_frame.locals[self.name]
+    )
+
     prop_func = objects.Property(
         function=self,
         name=self.name,
         lineno=self.lineno,
-        parent=self.parent,
+        parent=self.parent if not property_already_in_parent_locals else None,
         col_offset=self.col_offset,
     )
+    if property_already_in_parent_locals:
+        prop_func.parent = self.parent
     prop_func.postinit(body=[], args=self.args, doc_node=self.doc_node)
     yield prop_func
     return InferenceErrorInfo(node=self, context=context)

astroid/interpreter/objectmodel.py

@@ -25,6 +25,7 @@
 import os
 import pprint
 import types
+from functools import lru_cache
 from typing import TYPE_CHECKING, List, Optional
 
 import astroid
@@ -100,6 +101,7 @@ def __get__(self, instance, cls=None):
     def __contains__(self, name):
         return name in self.attributes()
 
+    @lru_cache()  # noqa
     def attributes(self) -> List[str]:
         """Get the attributes which are exported by this object model."""
         return [o[LEN_OF_IMPL_PREFIX:] for o in dir(self) if o.startswith(IMPL_PREFIX)]

astroid/manager.py

@@ -18,6 +18,7 @@
 from astroid.interpreter._import import spec
 from astroid.modutils import (
     NoSourceFile,
+    _cache_normalize_path_,
     file_info_from_modpath,
     get_source_file,
     is_module_name_part_of_extension_package_whitelist,
@@ -365,8 +366,24 @@ def bootstrap(self):
     def clear_cache(self) -> None:
         """Clear the underlying cache, bootstrap the builtins module and
         re-register transforms."""
+        # import here because of cyclic imports
+        # pylint: disable=import-outside-toplevel
+        from astroid.inference_tip import clear_inference_tip_cache
+        from astroid.interpreter.objectmodel import ObjectModel
+        from astroid.nodes.node_classes import LookupMixIn
+
+        clear_inference_tip_cache()
+
         self.astroid_cache.clear()
         AstroidManager.brain["_transform"] = TransformVisitor()
+
+        for lru_cache in (
+            LookupMixIn.lookup,
+            _cache_normalize_path_,
+            ObjectModel.attributes,
+        ):
+            lru_cache.cache_clear()
+
         self.bootstrap()
 
         # Reload brain plugins. During initialisation this is done in astroid.__init__.py

astroid/modutils.py

@@ -22,8 +22,9 @@
 import sys
 import sysconfig
 import types
+from functools import lru_cache
 from pathlib import Path
-from typing import Dict, Set
+from typing import Set
 
 from astroid.const import IS_JYTHON, IS_PYPY
 from astroid.interpreter._import import spec, util
@@ -138,21 +139,19 @@ def _handle_blacklist(blacklist, dirnames, filenames):
             filenames.remove(norecurs)
 
 
-_NORM_PATH_CACHE: Dict[str, str] = {}
+@lru_cache()
+def _cache_normalize_path_(path: str) -> str:
+    return _normalize_path(path)
 
 
 def _cache_normalize_path(path: str) -> str:
     """Normalize path with caching."""
     # _module_file calls abspath on every path in sys.path every time it's
     # called; on a larger codebase this easily adds up to half a second just
     # assembling path components. This cache alleviates that.
-    try:
-        return _NORM_PATH_CACHE[path]
-    except KeyError:
-        if not path:  # don't cache result for ''
-            return _normalize_path(path)
-        result = _NORM_PATH_CACHE[path] = _normalize_path(path)
-        return result
+    if not path:  # don't cache result for ''
+        return _normalize_path(path)
+    return _cache_normalize_path_(path)
 
 
 def load_module_from_name(dotted_name: str) -> types.ModuleType:

astroid/nodes/node_classes.py

@@ -367,7 +367,7 @@ def get_children(self):
 class LookupMixIn:
     """Mixin to look up a name in the right scope."""
 
-    @lru_cache(maxsize=None)  # pylint: disable=cache-max-size-none  # noqa
+    @lru_cache()  # noqa
     def lookup(self, name: str) -> typing.Tuple[str, typing.List[NodeNG]]:
         """Lookup where the given variable is assigned.
 

tests/unittest_manager.py

@@ -16,7 +16,9 @@
 from astroid import manager, test_utils
 from astroid.const import IS_JYTHON
 from astroid.exceptions import AstroidBuildingError, AstroidImportError
+from astroid.modutils import is_standard_module
 from astroid.nodes import Const
+from astroid.nodes.scoped_nodes import ClassDef
 
 from . import resources
 
@@ -317,6 +319,43 @@ def test_borg(self) -> None:
 
 
 class ClearCacheTest(unittest.TestCase, resources.AstroidCacheSetupMixin):
+    def test_clear_cache_clears_other_lru_caches(self) -> None:
+        lrus = (
+            astroid.nodes.node_classes.LookupMixIn.lookup,
+            astroid.modutils._cache_normalize_path_,
+            astroid.interpreter.objectmodel.ObjectModel.attributes,
+        )
+
+        # Get a baseline for the size of the cache after simply calling bootstrap()
+        baseline_cache_infos = [lru.cache_info() for lru in lrus]
+
+        # Generate some hits and misses
+        ClassDef().lookup("garbage")
+        is_standard_module("unittest", std_path=["garbage_path"])
+        astroid.interpreter.objectmodel.ObjectModel().attributes()
+
+        # Did the hits or misses actually happen?
+        incremented_cache_infos = [lru.cache_info() for lru in lrus]
+        for incremented_cache, baseline_cache in zip(
+            incremented_cache_infos, baseline_cache_infos
+        ):
+            with self.subTest(incremented_cache=incremented_cache):
+                self.assertGreater(
+                    incremented_cache.hits + incremented_cache.misses,
+                    baseline_cache.hits + baseline_cache.misses,
+                )
+
+        astroid.MANAGER.clear_cache()  # also calls bootstrap()
+
+        # The cache sizes are now as low or lower than the original baseline
+        cleared_cache_infos = [lru.cache_info() for lru in lrus]
+        for cleared_cache, baseline_cache in zip(
+            cleared_cache_infos, baseline_cache_infos
+        ):
+            with self.subTest(cleared_cache=cleared_cache):
+                # less equal because the "baseline" might have had multiple calls to bootstrap()
+                self.assertLessEqual(cleared_cache.currsize, baseline_cache.currsize)
+
     def test_brain_plugins_reloaded_after_clearing_cache(self) -> None:
         astroid.MANAGER.clear_cache()
         format_call = astroid.extract_node("''.format()")

tests/unittest_modutils.py

@@ -179,7 +179,7 @@ def test_load_packages_without_init(self) -> None:
         https://github.com/PyCQA/astroid/issues/1327
         """
         tmp_dir = Path(tempfile.gettempdir())
-        self.addCleanup(os.chdir, os.curdir)
+        self.addCleanup(os.chdir, os.getcwd())
         os.chdir(tmp_dir)
 
         self.addCleanup(shutil.rmtree, tmp_dir / "src")
@@ -288,6 +288,8 @@ def test_custom_path(self) -> None:
         self.assertTrue(
             modutils.is_standard_module("data.module", (os.path.abspath(datadir),))
         )
+        # "" will evaluate to cwd
+        self.assertTrue(modutils.is_standard_module("data.module", ("",)))
 
     def test_failing_edge_cases(self) -> None:
         # using a subpackage/submodule path as std_path argument