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Stewori / pytypes

Typing-toolbox for Python 3 _and_ 2.7 w.r.t. PEP 484.
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Incompatible types at # type: ignore #81

Open jolaf opened 5 years ago

jolaf commented 5 years ago

The following code:

from pytypes import TypeChecker

def f() -> None: # type: ignore # blah
    pass

with TypeChecker():
    f()

fails as follows:

$ python3 Test.py
/usr/local/lib/python3.6/dist-packages/pytypes-1.0b5.post23-py3.6.egg/pytypes/type_util.py:2534: UserWarning: the system profiling hook has changed unexpectedly
  warn('the system profiling hook has changed unexpectedly')
Traceback (most recent call last):
  File "Test.py", line 7, in <module>
    f()
  File "Test.py", line 3, in f
    def f() -> None: # type: ignore # blah
TypeError: __main__.f declares incompatible types:
Via hints:   (Tuple[], NoneType)
Via comment: None

The problem disappears if # blah is removed.

Stewori commented 5 years ago

Not a solution as this is actually a symptom of pytypes being unaware of ignore: You can work around this by setting pytypes.strict_annotation_collision_check = False.

Stewori commented 5 years ago

Ah, sorry; I recognized that this workaround wouldn't do it because pytypes still asserts that a concurrent type string to a type annotation would yield the same type. It would be an easy fix to disable this or to allow an opt-out of this check. However for the reason explained in https://github.com/Stewori/pytypes/issues/78#issuecomment-528878913 I won't fix this before end of next week.