Typeshed

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "typeshed"]
+	path = typeshed
+	url = http://github.com/python/typeshed

README.md

@@ -112,7 +112,7 @@ Quick start for contributing to mypy
 
 If you want to contribute, first clone the mypy git repository:
 
-    $ git clone https://github.com/JukkaL/mypy.git
+    $ git clone --recurse-submodules https://github.com/JukkaL/mypy.git
 
 Run the supplied `setup.py` script to install mypy:
 
@@ -130,6 +130,19 @@ The mypy wiki contains some useful information for contributors:
 
   http://www.mypy-lang.org/wiki/DeveloperGuides
 
+Working with the git version of mypy
+------------------------------------
+
+mypy contains a submodule, "typeshed". See http://github.com/python/typeshed.
+This submodule contains types for the Python standard library.
+
+Due to the way git submodules work, you'll have to do
+```
+  git submodule update typeshed
+```
+whenever you change branches, merge, rebase, or pull.
+
+(It's possible to automate this: Search Google for "git hook update submodule")
 
 Running tests and linting
 -------------------------

docs/source/basics.rst

@@ -124,8 +124,8 @@ explains how to download and install mypy.
 
 .. _library-stubs:
 
-Library stubs
-*************
+Typeshed
+********
 
 In order to type check code that uses library modules such as those
 included in the Python standard library, you need to have library
@@ -141,8 +141,9 @@ For example, consider this code:
 
 Without a library stub, the type checker has no way of inferring the
 type of ``x`` and checking that the argument to ``chr`` has a valid
-type. Mypy comes with a library stub for Python builtins that contains
-a definition like this for ``chr``:
+type. Mypy contains the `typeshed <http://github.com/python/typeshed>`_ project,
+which contains library stubs for Python builtins that contains a definition
+like this for ``chr``:
 
 .. code-block:: python
 
@@ -167,9 +168,13 @@ for module ``csv``, and use a subdirectory with ``__init__.pyi`` for packages.
 If there is both a ``.py`` and a ``.pyi`` file for a module, the ``.pyi`` file
 takes precedence. This way you can easily add annotations for a module even if
 you don't want to modify the source code. This can be useful, for example, if you
-use 3rd party open source libraries in your program. You can also override the stubs
-mypy uses for standard libary modules, in case you need to make local
-modifications.
+use 3rd party open source libraries in your program.
+
+You can also override the stubs mypy uses for standard libary modules, in case
+you need to make local modifications. (Note that if you want to submit your
+changes, please submit a pull request to `typeshed <http://github.com/python/typeshed>`_
+first, and then update the submodule in mypy using a commit that only touches
+the typeshed submodule and nothing else)
 
 That's it! Now you can access the module in mypy programs and type check
 code that uses the library. If you write a stub for a library module,

mypy/build.py

@@ -212,43 +212,28 @@ def default_lib_path(data_dir: str, target: int, pyversion: Tuple[int, int],
     if path_env is not None:
         path[:0] = path_env.split(os.pathsep)
 
-    # Add library stubs directory. By convention, they are stored in the
-    # stubs/x.y directory of the mypy installation. Additionally, stubs
-    # for earlier versions in the same major version will be added, and
-    # as a last resort, third-party stubs will be added.
-    if pyversion == 2:
-        major, minor = 2, 7
-    else:
-        # See bug #886
-        major, minor = sys.version_info[0], sys.version_info[1]
-    version_dir = '3.2'
-    third_party_dir = 'third-party-3.2'
-    if pyversion[0] < 3:
-        version_dir = '2.7'
-        third_party_dir = 'third-party-2.7'
-    path.append(os.path.join(data_dir, 'stubs', version_dir))
-    path.append(os.path.join(data_dir, 'stubs', third_party_dir))
-    path.append(os.path.join(data_dir, 'stubs-auto', version_dir))
-    if major == 3:
-        # Add additional stub directories.
-        versions = ['3.3', '3.4', '3.5', '3.6']
-        if False:
-            # Ick, we really should figure out how to use this again.
-            versions = ['3.%d' % i for i in range(minor, -1, -1)]
-        for v in versions:
-            stubdir = os.path.join(data_dir, 'stubs', v)
+    auto = os.path.join(data_dir, 'stubs-auto')
+    if os.path.isdir(auto):
+        data_dir = auto
+
+    # We allow a module for e.g. version 3.5 to be in 3.4/. The assumption
+    # is that a module added with 3.4 will still be present in Python 3.5.
+    versions = ["%d.%d" % (pyversion[0], minor)
+                for minor in reversed(range(pyversion[1] + 1))]
+    # E.g. for Python 3.5, try 2and3/, then 3/, then 3.5/, then 3.4/, 3.3/, ...
+    for v in ['2and3', str(pyversion[0])] + versions:
+        for lib_type in ['stdlib', 'builtins', 'third_party']:
+            stubdir = os.path.join(data_dir, 'typeshed', lib_type, v)
             if os.path.isdir(stubdir):
                 path.append(stubdir)
 
-            third_party_stubdir = os.path.join(data_dir, 'stubs', 'third-party-' + v)
-            if os.path.isdir(third_party_stubdir):
-                path.append(third_party_stubdir)
-
     # Add fallback path that can be used if we have a broken installation.
     if sys.platform != 'win32':
         path.append('/usr/local/lib/mypy')
 
     # Contents of Python's sys.path go last, to prefer the stubs
+    # TODO: To more closely model what Python actually does, builtins should
+    #       go first, then sys.path, then anything in stdlib and third_party.
     if python_path:
         path.extend(sys.path)
 

runtests.py

@@ -219,15 +219,16 @@ def add_stubs(driver: Driver) -> None:
     # Only test each module once, for the latest Python version supported.
     # The third-party stub modules will only be used if it is not in the version.
     seen = set()  # type: Set[str]
-    for version in driver.versions:
-        for pfx in ['', 'third-party-']:
-            stubdir = join('stubs', pfx + version)
+    # TODO: This should also test Python 2, and pass pyversion accordingly.
+    for version in ["2and3", "3", "3.3", "3.4", "3.5"]:
+        for stub_type in ['builtins', 'stdlib', 'third_party']:
+            stubdir = join('typeshed', stub_type, version)
             for f in find_files(stubdir, suffix='.pyi'):
                 module = file_to_module(f[len(stubdir) + 1:])
                 if module not in seen:
                     seen.add(module)
                     driver.add_mypy_string(
-                        'stub (%s) module %s' % (pfx + version, module),
+                        'stub (%s) module %s' % (stubdir, module),
                         'import typing, %s' % module)
 
 

setup.py

@@ -50,7 +50,7 @@ def find_data_files(base, globs):
 
 data_files = []
 
-data_files += find_data_files('stubs', ['*.py', '*.pyi'])
+data_files += find_data_files('typeshed', ['*.py', '*.pyi'])
 
 data_files += find_data_files('xml', ['*.xsd', '*.xslt', '*.css'])