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nedbat
Assume `if TYPE_CHECKING: ... else: ...` block is covered
if typing.TYPE_CHECKING blocks are never run but are still counted as needing test coverage.
( https://docs.python.org/3.7/library/typing.html#typing.TYPE_CHECKING )
Example
from typing import TYPE_CHECKING
if TYPE_CHECKING:
# coverage.py thinks this is not covered because TYPE_CHECKING is True at runtime
...
else:
....
You have to add # pragma: no_cover to the if block here because coverage.py assumes TYPE_CHECKING to be False, and therefore assumes one of the blocks does not have a test case. It would be good if you didn't have to, and blocks requiring TYPE_CHECKING to be True are assumed to not need test cases.
You can solve this yourself today by adding this to your .coveragerc file:
[report]
exclude_lines =
pragma: no cover
if TYPE_CHECKING:
More details about this setting are here: Advanced exclusion.
Since this is something that is configurable by the user, I would rather not change coverage.py to deal with it.
@nedbat - when would you expect code inside if TYPE_CHECKING blocks to be executed while code coverage measurement is in effect? How would you feel about making this part of the default exclude_lines?
A few years later, I think you are right that it should be part of the default. If the user wants to measure those lines, they can.
@ikonst - I'm not 100% sure that's a good idea, but also as I've painfully discovered, you really mean \.\.\..
Yeah, obviously in its escaped form. I think the sharp change in coverage would tell you :)
It can be quite the footgun when your projects are starting from 100% line coverage...
A few years later, I think you are right that it should be part of the default. If the user wants to measure those lines, they can.
@nedbat Is the else from a if not TYPE_CHECKING: supposed to be supported as well? If yes, any tips where I can implement this part?
