bug#66187: read-file-name unexpected behavior when MUSTMATCH is a function

[Michael Heerdegen]

Joseph Turner via "Bug reports for GNU Emacs, the Swiss army knife of
text editors" <bug-gnu-emacs@gnu.org> writes:

> My original expectations:
>
> - PREDICATE narrows the list of completion candidates
> - MUST-MATCH function determines whether to accept the input
> [...]

> > This is only about `read-file-name'
>
> Doesn't the unexpected behavior originate in completing-read?

If that's the behavioral aspect you mean, then yes, the meaning of the
arguments is analogue, and they are passed to `completing-read'.

Michael.