move cgi to 2and3 and add types (#1022)

* move cgi to 2and3 and add types

This is pretty stable between Python 2 and 3, and not very well documented.

* fix CI failures

* adjust comment

(want to force Travis to re-run)

* give up on overriding values

stdlib/2and3/cgi.pyi

@@ -0,0 +1,114 @@
+import sys
+from typing import Any, Dict, IO, Iterable, List, Mapping, Optional, Tuple, TypeVar, Union
+
+_T = TypeVar('_T', bound=FieldStorage)
+
+def parse(fp: IO[Any] = ..., environ: Mapping[str, str] = ...,
+          keep_blank_values: bool = ..., strict_parsing: bool = ...) -> Dict[str, List[str]]: ...
+def parse_qs(qs: str, keep_blank_values: bool = ..., strict_parsing: bool = ...) -> Dict[str, List[str]]: ...
+def parse_qsl(qs: str, keep_blank_values: bool = ..., strict_parsing: bool = ...) -> Dict[str, List[str]]: ...
+def parse_multipart(fp: IO[Any], pdict: Mapping[str, bytes]) -> Dict[str, List[bytes]]: ...
+def parse_header(s: str) -> Tuple[str, Dict[str, str]]: ...
+def test(environ: Mapping[str, str] = ...) -> None: ...
+def print_environ(environ: Mapping[str, str] = ...) -> None: ...
+def print_form(form: Dict[str, Any]) -> None: ...
+def print_directory() -> None: ...
+def print_environ_usage() -> None: ...
+def escape(s: str, quote: bool = ...) -> str: ...
+
+
+class MiniFieldStorage:
+    # The first five "Any" attributes here are always None, but mypy doesn't support that
+    filename = ...  # type: Any
+    list = ...  # type: Any
+    type = ...  # type: Any
+    file = ...  # type: Any
+    type_options = ...  # type: Dict[Any, Any]
+    disposition = ...  # type: Any
+    disposition_options = ...  # type: Dict[Any, Any]
+    headers = ...  # type: Dict[Any, Any]
+    name = ...  # type: Any
+    value = ...  # type: Any
+
+    def __init__(self, name: Any, value: Any) -> None: ...
+    def __repr__(self) -> str: ...
+
+
+class FieldStorage(object):
+    keep_blank_values = ...  # type: int
+    strict_parsing = ...  # type: int
+    qs_on_post = ...  # type: Optional[str]
+    headers = ...  # type: Mapping[str, str]
+    fp = ...  # type: IO[bytes]
+    encoding = ...  # type: str
+    errors = ...  # type: str
+    outerboundary = ...  # type: bytes
+    bytes_read = ...  # type: int
+    limit = ...  # type: Optional[int]
+    disposition = ...  # type: str
+    disposition_options = ...  # type: Dict[str, str]
+    filename = ...  # type: Optional[str]
+    type = ...  # type: str
+    type_options = ...  # type: Dict[str, str]
+    innerboundary = ...  # type: bytes
+    length = ...  # type: int
+    done = ...  # type: int
+    list = ...  # type: Optional[List[Any]]
+    value = ...  # type: Union[None, bytes, List[Any]]
+
+    if sys.version_info >= (3, 0):
+        def __init__(self, fp: IO[Any] = ..., headers: Mapping[str, str] = ..., outerboundary: bytes = ...,
+                     environ: Mapping[str, str] = ..., keep_blank_values: int = ..., strict_parsing: int = ...,
+                     limit: int = ..., encoding: str = ..., errors: str = ...) -> None: ...
+    else:
+        def __init__(self, fp: IO[Any] = ..., headers: Mapping[str, str] = ..., outerboundary: bytes = ...,
+                     environ: Mapping[str, str] = ..., keep_blank_values: int = ..., strict_parsing: int = ...) -> None: ...
+
+    if sys.version_info >= (3, 0):
+        def __enter__(self: _T) -> _T: ...
+        def __exit__(self, *args: Any) -> None: ...
+    def __repr__(self) -> str: ...
+    def __iter__(self) -> Iterable[str]: ...
+    def __getitem__(self, key: str) -> Any: ...
+    def getvalue(self, key: str, default: Any = ...) -> Any: ...
+    def getfirst(self, key: str, default: Any = ...) -> Any: ...
+    def getlist(self, key: str) -> List[Any]: ...
+    def keys(self) -> List[str]: ...
+    if sys.version_info < (3, 0):
+        def has_key(self, key: str) -> bool: ...
+    def __contains__(self, key: str) -> bool: ...
+    def __len__(self) -> int: ...
+    if sys.version_info >= (3, 0):
+        def __bool__(self) -> bool: ...
+    else:
+        def __nonzero__(self) -> bool: ...
+    if sys.version_info >= (3, 0):
+        # In Python 3 it returns bytes or str IO depending on an internal flag
+        def make_file(self) -> IO[Any]: ...
+    else:
+        # In Python 2 it always returns bytes and ignores the "binary" flag
+        def make_file(self, binary: Any = ...) -> IO[bytes]: ...
+
+
+if sys.version_info <= (3, 0):
+    from UserDict import UserDict
+
+    class FormContentDict(UserDict):
+        query_string = ...  # type: str
+        def __init__(self, environ: Mapping[str, str] = ..., keep_blank_values: int = ..., strict_parsing: int = ...) -> None: ...
+
+    class SvFormContentDict(FormContentDict):
+        def getlist(self, key: Any) -> Any: ...
+
+    class InterpFormContentDict(SvFormContentDict): ...
+
+    class FormContent(FormContentDict):
+        # TODO this should have
+        # def values(self, key: Any) -> Any: ...
+        # but this is incompatible with the supertype, and adding '# type: ignore' triggers
+        # a parse error in pytype (https://github.com/google/pytype/issues/53)
+        def indexed_value(self, key: Any, location: int) -> Any: ...
+        def value(self, key: Any) -> Any: ...
+        def length(self, key: Any) -> int: ...
+        def stripped(self, key: Any) -> Any: ...
+        def pars(self) -> Dict[Any, Any]: ...