From 2d96eecd3008272ea656b031c9fba81f49832580 Mon Sep 17 00:00:00 2001
From: Manuel Krebber <admin@wheerd.de>
Date: Wed, 3 May 2017 17:53:48 +0200
Subject: [PATCH] Itertools update (#1233)

* Updated the typehints for itertools.

* Removed the overload because it caused problems and cleaned up the imports.

* Update itertools.pyi

Added back optionality of second argument for itertools.permutations.

* Update itertools.pyi

Moved the Optional which I accidentially put on the wrong function -.-
---
 stdlib/3/itertools.pyi | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/stdlib/3/itertools.pyi b/stdlib/3/itertools.pyi
index 889d583c5..774d68fb3 100644
--- a/stdlib/3/itertools.pyi
+++ b/stdlib/3/itertools.pyi
@@ -3,7 +3,7 @@
 # Based on http://docs.python.org/3.2/library/itertools.html
 
 from typing import (Iterator, TypeVar, Iterable, overload, Any, Callable, Tuple,
-                    Union, Sequence, Generic, Optional)
+                    Generic, Optional)
 
 _T = TypeVar('_T')
 _S = TypeVar('_S')
@@ -44,20 +44,18 @@ def islice(iterable: Iterable[_T], stop: int) -> Iterator[_T]: ...
 def islice(iterable: Iterable[_T], start: int, stop: Optional[int],
            step: int = ...) -> Iterator[_T]: ...
 
-def starmap(func: Any, iterable: Iterable[Any]) -> Iterator[Any]: ...
+def starmap(func: Callable[..., _S], iterable: Iterable[Iterable[Any]]) -> Iterator[_S]: ...
 def takewhile(predicate: Callable[[_T], Any],
               iterable: Iterable[_T]) -> Iterator[_T]: ...
-def tee(iterable: Iterable[Any], n: int = ...) -> Iterator[Any]: ...
+def tee(iterable: Iterable[_T], n: int = ...) -> Tuple[Iterator[_T], ...]: ...
 def zip_longest(*p: Iterable[Any],
                 fillvalue: Any = ...) -> Iterator[Any]: ...
 
-# TODO: Return type should be Iterator[Tuple[..]], but unknown tuple shape.
-#       Iterator[Sequence[_T]] loses this type information.
-def product(*p: Iterable[_T], repeat: int = ...) -> Iterator[Sequence[_T]]: ...
+def product(*p: Iterable[_T], repeat: int = ...) -> Iterator[Tuple[_T, ...]]: ...
 
 def permutations(iterable: Iterable[_T],
-                 r: Union[int, None] = ...) -> Iterator[Sequence[_T]]: ...
+                 r: Optional[int] = ...) -> Iterator[Tuple[_T, ...]]: ...
 def combinations(iterable: Iterable[_T],
-                 r: int) -> Iterable[Sequence[_T]]: ...
+                 r: int) -> Iterable[Tuple[_T, ...]]: ...
 def combinations_with_replacement(iterable: Iterable[_T],
-                                  r: int) -> Iterable[Sequence[_T]]: ...
+                                  r: int) -> Iterable[Tuple[_T, ...]]: ...