Automatic PR labeler

[TomNicholas]

GH action to automatically label new PRs according to which files they touch.

Idea stolen from dask, see dask/dask#7506 . Their PR labelling by file/module is specified here.

(My first use of this bot so might well be a mistake.)

@max-sixty you will probably enjoy this extra automation 🤖

• User visible changes (including notable bug fixes) are documented in whats-new.rst

[max-sixty]

@max-sixty you will probably enjoy this extra automation 🤖

Haha thanks!! Prayers do get answered.

I guess it's imperfect if it's just doing the robotic thing — a formatting PR is going to get a whole lot of labels — ideally the process would understand its weight. But let's definitely give it a go!

[TomNicholas]

I guess it's imperfect if it's just doing the robotic thing — a formatting PR is going to get a whole lot of labels — ideally the process would understand its weight. But let's definitely give it a go!

Yeah that's a good point... But should happen relatively rarely hopefully. (Also I think if you're searching for relevant issues by topic you might prefer false positives than false negatives, so you don't miss anything important).

I was also hoping there might be an option to retrospectively label existing PRs but I don't see one.