Pygettext: allow extracting constant f-strings

[tomasr8]

Feature or enhancement

Proposal:

(Wasn't sure whether to categorize this as a bug or a feature, but went for latter to be safe)

Pygettext currently disallows all f-strings, even those which don't contain any formatted values such as f'foo'.
I propose to allow pygettext to extract constant f-strings. Ideally, your linter would warn you about such f-strings,
but there is no harm in allowing them.

As a precedent, both xgettext and babel allow constant f-strings (though in the case of xgettext it might be accidental since
xgettext also extracts non-constant f-strings).

In short, I propose that this is extracted:

_(f'foo')

while this remains disallowed:

_(f'foo {x}')

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-130154: Pygettext: allow extracting constant f-strings #130156

[StanFromIreland]

@picnixz Just out of curiosity why the "triaged" label?

[picnixz]

Because otherwise I will look at that issue again thinking that there is a missing label. Ideally I should always add that label to all issues that I've been looking at but that would be an overkill (generally, the presence of interpreter-core/stdlib/extension-modules labels is sufficient to indicate that I read the issue and that the labels are fine), but when we don't have a tools directory label, I'm left with the triaged label as an indication (ideally GH should show the project it belongs to)

[tomasr8]

I'm left with the triaged label as an indication (ideally GH should show the project it belongs to)

Yeah I think in the absence of a tools label, it makes sense to use triaged for these issues (but not for other issues that have appropriate labels, I think that would create too much noise)

[serhiy-storchaka]

I think there is no need in this feature. F-string is not a literal string, it is an expression. Furthermore, it would open a can of worms -- if constant f-strings are allowed, why not other constant expressions? So, in long term, this will be harmful, by requiring us to waste time on discussing other extensions.

Note also that f-string does not define a docstring. There is a virtue to be consistent.

[tomasr8]

The slippery slope argument makes sense, if we allow f-strings, then why not _('a' + 'b') etc..