Make pytype happy with the third_party click stubs. (#2966)

This also makes the flask stubs that depend on click parseable.

* In pytype_test, only parse files with the .pyi extension.
  (There's a README in third_party/2and3/click/.)
* Annotate with ContextManager rather than using the
  contextmanager decorator. This is shorter, removes a
  dependency, and gets rid of the slight weirdness of a
  decorator needing to be evaluated in a stub.
* Fix non-stub things.

Author: rchen152

tests/pytype_blacklist.txt

@@ -20,30 +20,7 @@ third_party/2and3/attr/converters.pyi
 third_party/2and3/attr/filters.pyi
 third_party/2and3/attr/validators.pyi
 third_party/2and3/boto/utils.pyi
-third_party/2and3/click/README.md
-third_party/2and3/click/__init__.pyi
-third_party/2and3/click/core.pyi
-third_party/2and3/click/decorators.pyi
-third_party/2and3/click/exceptions.pyi
-third_party/2and3/click/formatting.pyi
-third_party/2and3/click/globals.pyi
-third_party/2and3/click/parser.pyi
-third_party/2and3/click/termui.pyi
-third_party/2and3/click/testing.pyi
-third_party/2and3/click/types.pyi
 third_party/2and3/dateutil/rrule.pyi
-third_party/2and3/flask/__init__.pyi
-third_party/2and3/flask/app.pyi
-third_party/2and3/flask/blueprints.pyi
-third_party/2and3/flask/cli.pyi
-third_party/2and3/flask/ctx.pyi
-third_party/2and3/flask/debughelpers.pyi
-third_party/2and3/flask/globals.pyi
-third_party/2and3/flask/helpers.pyi
-third_party/2and3/flask/logging.pyi
-third_party/2and3/flask/templating.pyi
-third_party/2and3/flask/testing.pyi
-third_party/2and3/flask/views.pyi
 third_party/2and3/google/protobuf/any_pb2.pyi
 third_party/2and3/google/protobuf/any_test_pb2.pyi
 third_party/2and3/google/protobuf/api_pb2.pyi

tests/pytype_test.py

@@ -172,7 +172,7 @@ def _parse(filename, major_version):
 
     for root, _, filenames in itertools.chain.from_iterable(
             os.walk(p) for p in paths):
-        for f in sorted(filenames):
+        for f in sorted(f for f in filenames if f.endswith('.pyi')):
             f = os.path.join(root, f)
             rel = _get_relative(f)
             if not skipped.search(rel):

third_party/2and3/click/README.md

@@ -1,7 +1,7 @@
 # click 6.6, Python 3
 
-`__init__.pyi` is literally a copy of click/__init__.py. It's a shortcut module
-anyway in the actual sources so it works well without additional changes.
+`__init__.pyi` is almost a copy of `click/__init__.py`. It's a shortcut module
+anyway in the actual sources so it works well with minimal changes.
 
 The types are pretty complete but they were created mostly for public API use
 so some internal modules (`_compat`) or functions (`core._bashcomplete`) are

third_party/2and3/click/__init__.pyi

@@ -108,49 +108,9 @@ from .formatting import HelpFormatter as HelpFormatter, wrap_text as wrap_text
 # Parsing
 from .parser import OptionParser as OptionParser
 
-
-__all__ = [
-    # Core classes
-    'Context', 'BaseCommand', 'Command', 'MultiCommand', 'Group',
-    'CommandCollection', 'Parameter', 'Option', 'Argument',
-
-    # Globals
-    'get_current_context',
-
-    # Decorators
-    'pass_context', 'pass_obj', 'make_pass_decorator', 'command', 'group',
-    'argument', 'option', 'confirmation_option', 'password_option',
-    'version_option', 'help_option',
-
-    # Types
-    'ParamType', 'File', 'Path', 'Choice', 'IntRange', 'Tuple', 'STRING',
-    'INT', 'FLOAT', 'BOOL', 'UUID', 'UNPROCESSED',
-
-    # Utilities
-    'echo', 'get_binary_stream', 'get_text_stream', 'open_file',
-    'format_filename', 'get_app_dir', 'get_os_args',
-
-    # Terminal functions
-    'prompt', 'confirm', 'get_terminal_size', 'echo_via_pager',
-    'progressbar', 'clear', 'style', 'unstyle', 'secho', 'edit', 'launch',
-    'getchar', 'pause',
-
-    # Exceptions
-    'ClickException', 'UsageError', 'BadParameter', 'FileError',
-    'Abort', 'NoSuchOption', 'BadOptionUsage', 'BadArgumentUsage',
-    'MissingParameter',
-
-    # Formatting
-    'HelpFormatter', 'wrap_text',
-
-    # Parsing
-    'OptionParser',
-]
-
-
 # Controls if click should emit the warning about the use of unicode
 # literals.
-disable_unicode_literals_warning = False
+disable_unicode_literals_warning: bool
 
 
-__version__ = '6.6'
+__version__: str

third_party/2and3/click/core.pyi

@@ -1,7 +1,7 @@
-from contextlib import contextmanager
 from typing import (
     Any,
     Callable,
+    ContextManager,
     Dict,
     Generator,
     Iterable,
@@ -28,10 +28,9 @@ def invoke_param_callback(
     ...
 
 
-@contextmanager
 def augment_usage_errors(
     ctx: Context, param: Optional[Parameter] = ...
-) -> Generator[None, None, None]:
+) -> ContextManager[None]:
     ...
 
 
@@ -90,8 +89,7 @@ class Context:
     ) -> None:
         ...
 
-    @contextmanager
-    def scope(self, cleanup: bool = ...) -> Generator[Context, None, None]:
+    def scope(self, cleanup: bool = ...) -> ContextManager[Context]:
         ...
 
     def make_formatter(self) -> HelpFormatter:

third_party/2and3/click/formatting.pyi

@@ -1,5 +1,4 @@
-from contextlib import contextmanager
-from typing import Generator, Iterable, List, Optional, Tuple
+from typing import ContextManager, Generator, Iterable, List, Optional, Tuple
 
 
 FORCED_WIDTH: Optional[int]
@@ -73,12 +72,10 @@ class HelpFormatter:
     ) -> None:
         ...
 
-    @contextmanager
-    def section(self, name) -> Generator[None, None, None]:
+    def section(self, name) -> ContextManager[None]:
         ...
 
-    @contextmanager
-    def indentation(self) -> Generator[None, None, None]:
+    def indentation(self) -> ContextManager[None]:
         ...
 
     def getvalue(self) -> str:

third_party/2and3/click/types.pyi

@@ -261,9 +261,9 @@ def convert_type(ty: Optional[_ConvertibleType], default: Optional[Any] = ...) -
 
 # parameter type shortcuts
 
-BOOL = BoolParamType()
-FLOAT = FloatParamType()
-INT = IntParamType()
-STRING = StringParamType()
-UNPROCESSED = UnprocessedParamType()
-UUID = UUIDParameterType()
+BOOL: BoolParamType
+FLOAT: FloatParamType
+INT: IntParamType
+STRING: StringParamType
+UNPROCESSED: UnprocessedParamType
+UUID: UUIDParameterType