Fix it

Author: ericsnowcurrently

Lib/importlib/_bootstrap.py

@@ -843,14 +843,21 @@ def _setup_module(cls, module):
             spec.loader_state.origname = origname
 
     @classmethod
-    def _resolve_filename(cls, fullname, ispkg):
+    def _resolve_filename(cls, fullname, alias=None, ispkg=False):
         if not fullname or not getattr(sys, '_stdlib_dir', None):
             return None, None
         try:
             sep = cls._SEP
         except AttributeError:
             sep = cls._SEP = '\\' if sys.platform == 'win32' else '/'
 
+        if fullname != alias:
+            if fullname.startswith('<'):
+                fullname = fullname[1:]
+                if not ispkg:
+                    fullname = f'{fullname}.__init__'
+            else:
+                ispkg = False
         relfile = fullname.replace('.', sep)
         if ispkg:
             pkgdir = f'{sys._stdlib_dir}{sep}{relfile}'
@@ -869,7 +876,7 @@ def find_spec(cls, fullname, path=None, target=None):
         spec = spec_from_loader(fullname, cls,
                                 origin=cls._ORIGIN,
                                 is_package=ispkg)
-        filename, pkgdir = cls._resolve_filename(origname, ispkg)
+        filename, pkgdir = cls._resolve_filename(origname, fullname, ispkg)
         spec.loader_state = type(sys.implementation)(
             data=data,
             filename=filename,

Lib/test/test_frozen.py

@@ -39,9 +39,6 @@ def test_frozen_submodule_in_unfrozen_package(self):
         self.assertIs(spam.__spec__.loader,
                       importlib.machinery.FrozenImporter)
 
-    # This is not possible until frozen packages have __path__ set properly.
-    # See https://bugs.python.org/issue21736.
-    @unittest.expectedFailure
     def test_unfrozen_submodule_in_frozen_package(self):
         with import_helper.CleanImport('__phello__', '__phello__.spam'):
             with import_helper.frozen_modules(enabled=True):

Lib/test/test_importlib/frozen/test_finder.py

@@ -62,17 +62,24 @@ def check_loader_state(self, spec, origname=None, filename=None):
         # Check the rest of spec.loader_state.
         expected = dict(
             origname=origname,
-            filename=filename,
+            filename=filename if origname else None,
         )
         self.assertDictEqual(actual, expected)
 
-    def check_search_location(self, spec):
+    def check_search_locations(self, spec):
+        """This is only called when testing packages."""
         missing = object()
         filename = getattr(spec.loader_state, 'filename', missing)
-        if filename is missing:
+        origname = getattr(spec.loader_state, 'origname', None)
+        if not origname or filename is missing:
             # We deal with this in check_loader_state().
             return
-        expected = [os.path.dirname(filename)] if filename else []
+        if not filename:
+            expected = []
+        elif origname != spec.name and not origname.startswith('<'):
+            expected = []
+        else:
+            expected = [os.path.dirname(filename)]
         self.assertListEqual(spec.submodule_search_locations, expected)
 
     def test_module(self):

Lib/test/test_importlib/frozen/test_loader.py

@@ -3,10 +3,11 @@
 
 machinery = util.import_importlib('importlib.machinery')
 
-from test.support import captured_stdout, import_helper
+from test.support import captured_stdout, import_helper, STDLIB_DIR
 import _imp
 import contextlib
 import marshal
+import os.path
 import types
 import unittest
 import warnings
@@ -30,6 +31,14 @@ def fresh(name, *, oldapi=False):
                 yield
 
 
+def resolve_stdlib_file(name, ispkg=False):
+    assert name
+    if ispkg:
+        return os.path.join(STDLIB_DIR, *name.split('.'), '__init__.py')
+    else:
+        return os.path.join(STDLIB_DIR, *name.split('.')) + '.py'
+
+
 class ExecModuleTests(abc.LoaderTests):
 
     def exec_module(self, name, origname=None):
@@ -44,6 +53,7 @@ def exec_module(self, name, origname=None):
             loader_state=types.SimpleNamespace(
                 data=marshal.dumps(code),
                 origname=origname or name,
+                filename=resolve_stdlib_file(origname or name, is_package),
             ),
         )
         module = types.ModuleType(name)