Fix manager.clear_cache() not fully clearing the module cache (#2572) (#2573)

(cherry picked from commit 58286a1) Co-authored-by: Akhil Kamat <akhil.kamat@gmail.com>

Author: jacobtylerwalls

ChangeLog

@@ -13,7 +13,9 @@ What's New in astroid 3.3.4?
 ============================
 Release date: TBA
 
+* Fix bug with ``manager.clear_cache()`` not fully clearing cache
 
+ Refs https://github.com/pylint-dev/pylint/pull/9932#issuecomment-2364985551
 
 What's New in astroid 3.3.3?
 ============================

astroid/manager.py

@@ -464,6 +464,8 @@ def clear_cache(self) -> None:
  _invalidate_cache() # inference context cache
 
  self.astroid_cache.clear()
+ self._mod_file_cache.clear()
+
  # NB: not a new TransformVisitor()
  AstroidManager.brain["_transform"].transforms = collections.defaultdict(list)
 

tests/test_manager.py

@@ -491,6 +491,32 @@ def test_clear_cache_clears_other_lru_caches(self) -> None:
  # less equal because the "baseline" might have had multiple calls to bootstrap()
  self.assertLessEqual(cleared_cache.currsize, baseline_cache.currsize)
 
+ def test_file_cache_after_clear_cache(self) -> None:
+ """Test to mimic the behavior of how pylint lints file and
+ ensure clear cache clears everything stored in the cache.
+ See https://github.com/pylint-dev/pylint/pull/9932#issuecomment-2364985551
+ for more information.
+ """
+ orig_sys_path = sys.path[:]
+ try:
+ search_path = resources.RESOURCE_PATH
+ sys.path.insert(0, search_path)
+ node = astroid.MANAGER.ast_from_file(resources.find("data/cache/a.py"))
+ self.assertEqual(node.name, "cache.a")
+
+ # This import from statement should succeed and update the astroid cache
+ importfrom_node = astroid.extract_node("from cache import a")
+ importfrom_node.do_import_module(importfrom_node.modname)
+ finally:
+ sys.path = orig_sys_path
+
+ astroid.MANAGER.clear_cache()
+
+ importfrom_node = astroid.extract_node("from cache import a")
+ # Try import from again after clear cache, this should raise an error
+ with self.assertRaises(AstroidBuildingError):
+ importfrom_node.do_import_module(importfrom_node.modname)
+
  def test_brain_plugins_reloaded_after_clearing_cache(self) -> None:
  astroid.MANAGER.clear_cache()
  format_call = astroid.extract_node("''.format()")

tests/testdata/python3/data/cache/__init__.py

@@ -0,0 +1 @@
+""" Test for clear cache. Doesn't need anything here"""