import System.Collections.Generic as C

def test_contains():
 l = C.List[int]()
 l.Add(42)
 assert 42 in l
 assert 43 not in l

def test_dict_items():
 d = C.Dictionary[int, str]()
 d[42] = "a"
 items = d.items()
 assert len(items) == 1
 k,v = items[0]
 assert k == 42
 assert v == "a"

# regression test for https://github.com/pythonnet/pythonnet/issues/1785
def test_dict_in_keys():
 d = C.Dictionary[str, int]()
 d["a"] = 42
 assert "a" in d.Keys
 assert "b" not in d.Keys