Add regression test for #859 (#1468)

python · May 3, 2016 · 410bf37 · 410bf37
1 parent 3acdf54
commit 410bf37
Showing 1 changed file with 10 additions and 0 deletions.
diff --git a/mypy/test/data/pythoneval.test b/mypy/test/data/pythoneval.test
@@ -1153,3 +1153,13 @@ b = B()
 print(b.x + 1)
 [out]
 4
+
+[case testInferenceWithLambda]
+from typing import TypeVar, Iterable, Iterator
+import itertools
+
+_T = TypeVar('_T')
+
+def f(iterable): # type: (Iterable[_T]) -> Iterator[List[_T]]
+ grouped = itertools.groupby(enumerate(iterable), lambda pair: pair[0] // 2)
+ return ([elem for _, elem in group] for _, group in grouped)