bug#49776: 28.0.50; Incorrect username completion results reported by `read-file-name-interal`

[Lars Ingebrigtsen <larsi@gnus.org>]

Daniel Mendler <mail@daniel-mendler.de> writes:

> I am not looking at this as a user. I am investigating odd completion
> results in my Vertico completion UI (on GNU ELPA), when completing file
> names. If you type "~/etc/~man", you see these odd candidates
> "/etc/~man", where "/etc/" is actually part of the shadowed path. So to
> say it differently, I don't expect the shadowed path to take part in the
> completion.

Ah, right.

> Maybe Stefan can chime in here and explain some of the background. I've
> corresponded with him before a few times regarding how the completion
> machinery works internally.

Right.  Stefan, in short -- the thing we're wondering is whether this is
correct: 

(read-file-name-internal "~/foo/~man" nil t)
=> (#("/foo/~man/" 0 9 (face completions-common-part)))

(read-file-name-internal "./foo/~man" nil t)
=> (#("man/" 0 3 (face completions-common-part)))

I'd kinda expect both to give the same result (i.e., the latter result)?

(And "man" is a valid user in this scenario.)

-- 
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   bloggy blog: http://lars.ingebrigtsen.no