Allow using # type: ignore to skip type checking in a file

[JukkaL]

As per PEP 484 discussion, it should be possible to use # type: ignore to skip type checking in the rest of a file:

# type: ignore
... # ignore type errors here

Currently the comment can only be used to ignore errors on individual lines.

[gvanrossum]

(Moved assignment and Milestone from the duplicate #964.)

[JukkaL]

I wonder what we should do if this happens within a function. Should we then ignore all errors within the function only? Example:

def f() -> None:
    # type: ignore
    return 1 + 'x'   # don't report an error?

a = 1 + 'y'   # report an error here?

This could be nice, as it would let people annotate functions but ignore errors in the body of the function. @no_type_check is not a good match, as it also causes the annotations to be ignored.

[gvanrossum]

Yeah, I agree that this should be block-scoped.

[sacha-senchuk]

Hello,

Alternatively, could there be a way to exclude certain files or directories from command line or in the configuration file?

Currently, if I type mypy my_directory, the entire folder is scanned. It would be very handy to be able to add an --exclude argument.

In my case, I want to exclude automatically created Django migration files, but still scan my entire Django app.

[gvanrossum]

You can use the `ignore_errors` per-file option.

[sacha-senchuk]

Thank you @gvanrossum, this seems to be what I was looking for.

Could you please assist me a bit further? I tried to follow the instructions, but something is still not working:

mypy.ini

[mypy]

[gw_box.migrations.*]
ignore_errors = True

$ mypy gw_box --ignore-missing-imports --config-file mypy.ini
gw_box/migrations/0001_initial.py:14: error: Need type annotation for variable