fixup path comparison

astroid/interpreter/_import/util.py

@@ -15,7 +15,12 @@
 
 @lru_cache(maxsize=4096)
 def is_namespace(modname: str) -> bool:
-    from astroid.modutils import EXT_LIB_DIRS  # pylint: disable=import-outside-toplevel
+    from astroid.modutils import (  # pylint: disable=import-outside-toplevel
+        EXT_LIB_DIRS,
+        STD_LIB_DIRS,
+    )
+
+    STD_AND_EXT_LIB_DIRS = STD_LIB_DIRS.union(EXT_LIB_DIRS)
 
     if modname in sys.builtin_module_names:
         return False
@@ -75,7 +80,7 @@ def is_namespace(modname: str) -> bool:
         # Update last_submodule_search_locations
         if found_spec and found_spec.submodule_search_locations:
             if any(
-                location in EXT_LIB_DIRS
+                any(location.startswith(lib_dir) for lib_dir in STD_AND_EXT_LIB_DIRS)
                 for location in found_spec.submodule_search_locations
             ):
                 return False

tests/unittest_manager.py

@@ -128,24 +128,10 @@ def test_submodule_homonym_with_non_module(self) -> None:
         )
 
     def test_module_is_not_namespace(self) -> None:
-        def debug_result():
-            import sysconfig
-            from importlib.util import _find_spec_from_path
-
-            tested = list(EXT_LIB_DIRS)[0].rsplit("/", maxsplit=1)[-1]
-            spec = _find_spec_from_path(tested)
-            return (
-                f"SYCONFIG PATHS: {sysconfig.get_paths()}\n"
-                f"EXT_LIB_DIRS: {EXT_LIB_DIRS}\n"
-                f"TESTED: {tested}\n"
-                f"SPEC VARS: {vars(spec)}"
-            )
-
         self.assertFalse(util.is_namespace("tests.testdata.python3.data.all"))
         self.assertFalse(util.is_namespace("__main__"))
         self.assertFalse(
             util.is_namespace(list(EXT_LIB_DIRS)[0].rsplit("/", maxsplit=1)[-1]),
-            debug_result(),
         )
         self.assertFalse(util.is_namespace("importlib._bootstrap"))