[AIRFLOW-5063] Fix performance when switching between master/v1-10

[potiuk]

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  • https://issues.apache.org/jira/browse/AIRFLOW-5063

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[ashb]

This commit has changed the behaviour of mypy airflow/some/file.py -- it's ignoring the settings we have in setup.cfg because mypy.ini now exists and is empty.

$ mypy airflow/operators/docker_operator.py
mypy.ini: No [mypy] section in config file
airflow/www/widgets.py:20: error: Cannot find module named 'flask_appbuilder.widgets'

I don't get how this helps with switching branches even ignoring this bug above? Edit okay looked at the rest of the PR and that makes sense. I think we just shouldn't have this empty mypy.ini file, right?

[potiuk]

Let me take a look - there should not be mypy.ini in there. But it was in one of my local trials (abandoned). Might be a bad cherry-pick

[potiuk]

Oh yeah. Accidentally committed empty mypy.ini when cherry-picked it. Clue of that change was exclusion of www_rbac old folder from find - when you switch between v1-10-test and master branches, this folder remains in your sources and when you mount it in MacOS, scanning the folder takes 30-40 seconds in docker (because of slow osxfs)