Move mypy_extensions stubs to typeshed/stubs/mypy-extensions (python#…

…10527)

This fixes `--custom-typeshed-dir`.

misc/sync-typeshed.py

@@ -37,15 +37,18 @@ def update_typeshed(typeshed_dir: str, commit: Optional[str]) -> str:
     if commit:
         subprocess.run(['git', 'checkout', commit], check=True, cwd=typeshed_dir)
     commit = git_head_commit(typeshed_dir)
-    stub_dir = os.path.join('mypy', 'typeshed', 'stdlib')
+    stdlib_dir = os.path.join('mypy', 'typeshed', 'stdlib')
     # Remove existing stubs.
-    shutil.rmtree(stub_dir)
+    shutil.rmtree(stdlib_dir)
     # Copy new stdlib stubs.
-    shutil.copytree(os.path.join(typeshed_dir, 'stdlib'), stub_dir)
+    shutil.copytree(os.path.join(typeshed_dir, 'stdlib'), stdlib_dir)
     # Copy mypy_extensions stubs. We don't want to use a stub package, since it's
     # treated specially by mypy and we make assumptions about what's there.
-    shutil.copy(os.path.join(typeshed_dir, 'stubs', 'mypy-extensions', 'mypy_extensions.pyi'),
-                stub_dir)
+    stubs_dir = os.path.join('mypy', 'typeshed', 'stubs')
+    shutil.rmtree(stubs_dir)
+    os.makedirs(stubs_dir)
+    shutil.copytree(os.path.join(typeshed_dir, 'stubs', 'mypy-extensions'),
+                    os.path.join(stubs_dir, 'mypy-extensions'))
     return commit
 
 

mypy/modulefinder.py

@@ -544,6 +544,7 @@ def default_lib_path(data_dir: str,
 
     if custom_typeshed_dir:
         typeshed_dir = os.path.join(custom_typeshed_dir, "stdlib")
+        mypy_extensions_dir = os.path.join(custom_typeshed_dir, "stubs", "mypy-extensions")
         versions_file = os.path.join(typeshed_dir, "VERSIONS")
         if not os.path.isdir(typeshed_dir) or not os.path.isfile(versions_file):
             print("error: --custom-typeshed-dir does not point to a valid typeshed ({})".format(
@@ -554,12 +555,17 @@ def default_lib_path(data_dir: str,
         if os.path.isdir(auto):
             data_dir = auto
         typeshed_dir = os.path.join(data_dir, "typeshed", "stdlib")
+        mypy_extensions_dir = os.path.join(data_dir, "typeshed", "stubs", "mypy-extensions")
     if pyversion[0] == 2:
         # Python 2 variants of certain stdlib modules are in a separate directory.
         python2_dir = os.path.join(typeshed_dir, PYTHON2_STUB_DIR)
         path.append(python2_dir)
     path.append(typeshed_dir)
 
+    # Get mypy-extensions stubs from typeshed, since we treat it as an
+    # "internal" library, similar to typing and typing-extensions.
+    path.append(mypy_extensions_dir)
+
     # Add fallback path that can be used if we have a broken installation.
     if sys.platform != 'win32':
         path.append('/usr/local/lib/mypy')

mypy/typeshed/stubs/mypy-extensions/METADATA.toml

@@ -0,0 +1,2 @@
+version = "0.4"
+python2 = true