Argument Clinic: Enforce summary line length

[AA-Turner]

Feature or enhancement

Proposal:

Argument Clinic currently requires that a summary line exists, but places no further restrictions on the content.

There are 32 instances of a docstring over 100 characters long, with the longest at 148 characters (_sre.SRE_Pattern.subn / re.Pattern.subn). Long lines like this become hard to read, for example in help or pydoc output.

I propose that we start enforcing a maximum length of 80 characters for new docstrings, but use a whitelist so that we don't need to change existing overly long docstrings (for now).

A

cc @erlend-aasland @serhiy-storchaka

Has this already been discussed elsewhere?

This is a minor feature, which does not need previous discussion elsewhere

Links to previous discussion of this feature:

No response

Linked PRs

• GH-137623: Begin enforcing docstring length in Argument Clinic #137624

[serhiy-storchaka]

PEP 8 requires limiting docstring lines to 72 characters. pydoc adds 8 characters for functions and classes, so the total length is 80. It adds 12 characters for methods, so the limit may be 68 for them.