Standardize type comments

[13Ducks]

Description

Fixes #2097 and standardizes type comments to always have 1 space after the # and 1 space after the :

As per the issue, the functions is_type_comment() and contains_pragma_comment() have been modified to return true even with any extra whitespace. Type comments without non-breaking spaces are now stripped of any extra whitespace as well.

Waiting on confirmation from the issue that spaces before the : are acceptable (# type : something).

Checklist - did you ...

• Add a CHANGELOG entry if necessary?
• Add / update tests if necessary?
• Add new / update outdated documentation?

^ Is documentation needed for this change? If so, I can add it.

[ichard26]

This was discussed on Python Discord but the summary of it is that we can't really normalize type comments until all of the major AST libraries that provide first-class type comment support are liberal in the whitespace they understand. It wouldn't be good to have a type comment that's ignored by typed-ast transformed into one that is noticed which then affects a type checker like mypy.

We might be able to normalize type comments on newer Python versions since typed-ast is mostly used to provide Python 2 support but this will need further investigatio.

[JelleZijlstra]

I don't remember the discussion @ichard26 alludes to above. Could you provide some details on how existing tools (typed-ast, pyright, pyre, ...) interpret spaces in type comments?

[github-actions]

diff-shades results comparing this PR (505634a) to main (b517dfb). The full diff is available in the logs under the "Generate HTML diff report" step.

╭─────────────────────── Summary ────────────────────────╮
│ 2 projects & 13 files changed / 36 changes [+18/-18]   │
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│ ... out of 2 072 601 lines, 10 153 files & 23 projects │
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Differences found.

What is this? | Workflow run | diff-shades documentation

[ichard26]

Before I forget to link it again: https://discord.com/channels/267624335836053506/846434317021741086/921790074922864670

[CarliJoy]

Suggested change

	if re.match(r"#\s*(type\s*:|pylint\s*:|noqa\s*)", comment.value):
	if re.match(r"#\s*(type\s*:|pylint\s*:|noqa\s*|nosec\s*)", comment.value):

Would be nice if Bandit is supported as well.

[CarliJoy]

@13Ducks giving up on this MR ?