def _combine_multiple_returns(self, signatures):
"""Combines multiple return types.
Args:
signatures: The candidate signatures.
Returns:
The combined return type.
"""
options = []
for sig, _, _ in signatures:
t = sig.pytd_sig.return_type
params = pytd_utils.GetTypeParameters(t)
if params:
replacement = {}
for param_type in params:
replacement[param_type] = pytd.AnythingType()
replace_visitor = visitors.ReplaceTypeParameters(replacement)
t = t.Visit(replace_visitor)
options.append(t)
if len(set(options)) == 1:
return options[0]
# Optimizing and then removing unions allows us to preserve as much
# precision as possible while avoiding false positives.
ret_type = optimize.Optimize(pytd_utils.JoinTypes(options))
return ret_type.Visit(visitors.ReplaceUnionsWithAny())
def testAnyReplacement(self):
union = pytd.UnionType((pytd.NamedType("a"), pytd.NamedType("b")))
self.assertEqual(
union.Visit(visitors.ReplaceUnionsWithAny()), pytd.AnythingType())
