collections: convert from module to package

Making room for collections.abc

stdlib/3/collections/__init__.pyi

@@ -0,0 +1,134 @@
+# Stubs for collections
+
+# Based on http://docs.python.org/3.2/library/collections.html
+
+# TODO more abstract base classes (interfaces in mypy)
+
+# These are not exported.
+from typing import (
+    TypeVar, Iterable, Generic, Iterator, Dict, overload,
+    Mapping, List, Tuple, Callable, Sized,
+    Optional, Union
+)
+# These are exported.
+# TODO reexport more.
+from typing import (
+    MutableMapping as MutableMapping,
+    Sequence as Sequence,
+    MutableSequence as MutableSequence,
+    AbstractSet as Set,
+)
+
+_T = TypeVar('_T')
+_KT = TypeVar('_KT')
+_VT = TypeVar('_VT')
+
+
+# namedtuple is special-cased in the type checker; the initializer is ignored.
+namedtuple = object()
+
+class UserDict(MutableMapping): ...
+class UserList(MutableSequence): ...
+class UserString(Sequence): ...
+class MutableString(UserString, MutableSequence): ...
+
+# Technically, deque only derives from MutableSequence in 3.5.
+# But in practice it's not worth losing sleep over.
+class deque(MutableSequence[_T], Generic[_T]):
+    maxlen = 0 # type: Optional[int] # TODO readonly
+    def __init__(self, iterable: Iterable[_T] = ...,
+                 maxlen: int = ...) -> None: ...
+    def append(self, x: _T) -> None: ...
+    def appendleft(self, x: _T) -> None: ...
+    def insert(self, i: int, x: _T) -> None: ...
+    def clear(self) -> None: ...
+    def count(self, x: _T) -> int: ...
+    def extend(self, iterable: Iterable[_T]) -> None: ...
+    def extendleft(self, iterable: Iterable[_T]) -> None: ...
+    def pop(self, i: int = ...) -> _T: ...
+    def popleft(self) -> _T: ...
+    def remove(self, value: _T) -> None: ...
+    def reverse(self) -> None: ...
+    def rotate(self, n: int) -> None: ...
+
+    def __len__(self) -> int: ...
+    def __iter__(self) -> Iterator[_T]: ...
+    def __str__(self) -> str: ...
+    def __hash__(self) -> int: ...
+
+    # These methods of deque don't really take slices, but we need to
+    # define them as taking a slice to satisfy MutableSequence.
+    @overload
+    def __getitem__(self, index: int) -> _T: ...
+    @overload
+    def __getitem__(self, s: slice) -> Sequence[_T]: raise TypeError
+    @overload
+    def __setitem__(self, i: int, x: _T) -> None: ...
+    @overload
+    def __setitem__(self, s: slice, o: Sequence[_T]) -> None: raise TypeError
+    @overload
+    def __delitem__(self, i: int) -> None: ...
+    @overload
+    def __delitem__(self, s: slice) -> None: raise TypeError
+
+    def __contains__(self, o: object) -> bool: ...
+
+    # TODO __reversed__
+
+
+class Counter(Dict[_T, int], Generic[_T]):
+    @overload
+    def __init__(self) -> None: ...
+    @overload
+    def __init__(self, Mapping: Mapping[_T, int]) -> None: ...
+    @overload
+    def __init__(self, iterable: Iterable[_T]) -> None: ...
+    # TODO keyword arguments
+
+    def elements(self) -> Iterator[_T]: ...
+
+    @overload
+    def most_common(self) -> List[_T]: ...
+    @overload
+    def most_common(self, n: int) -> List[_T]: ...
+
+    @overload
+    def subtract(self, Mapping: Mapping[_T, int]) -> None: ...
+    @overload
+    def subtract(self, iterable: Iterable[_T]) -> None: ...
+
+    # The Iterable[Tuple[...]] argument type is not actually desirable
+    # (the tuples will be added as keys, breaking type safety) but
+    # it's included so that the signature is compatible with
+    # Dict.update. Not sure if we should use '# type: ignore' instead
+    # and omit the type from the union.
+    def update(self, m: Union[Mapping[_T, int],
+                              Iterable[Tuple[_T, int]],
+                              Iterable[_T]]) -> None: ...
+
+class OrderedDict(Dict[_KT, _VT], Generic[_KT, _VT]):
+    def popitem(self, last: bool = ...) -> Tuple[_KT, _VT]: ...
+    def move_to_end(self, key: _KT, last: bool = ...) -> None: ...
+
+
+class defaultdict(Dict[_KT, _VT], Generic[_KT, _VT]):
+    default_factory = ...  # type: Callable[[], _VT]
+
+    @overload
+    def __init__(self) -> None: ...
+    @overload
+    def __init__(self, map: Mapping[_KT, _VT]) -> None: ...
+    @overload
+    def __init__(self, iterable: Iterable[Tuple[_KT, _VT]]) -> None: ...
+    @overload
+    def __init__(self, default_factory: Callable[[], _VT]) -> None: ...
+    @overload
+    def __init__(self, default_factory: Callable[[], _VT],
+                 map: Mapping[_KT, _VT]) -> None: ...
+    @overload
+    def __init__(self, default_factory: Callable[[], _VT],
+                 iterable: Iterable[Tuple[_KT, _VT]]) -> None: ...
+    # TODO __init__ keyword args
+
+    def __missing__(self, key: _KT) -> _VT: ...
+    # TODO __reversed__