bug#28615: [PATCH] Clarify what grep-read-files wants

[Allen Li]

On Mon, Oct 9, 2017 at 10:55 PM, Eli Zaretskii <eliz@gnu.org> wrote:
>> From: Allen Li <vianchielfaura@gmail.com>
>> Date: Mon, 9 Oct 2017 21:43:59 -0700
>> Cc: 28615-done@debbugs.gnu.org
>>
>> Why did you not change the collection function?
>
> Because there could be a file called literally like one of the
> shorthands in grep-files-aliases, or whose name includes those
> shorthands as a substring.

Not sure what you mean.  There is no use case for completing a
file name.  Are you saying that a user might mistake the completion
on grep-files-aliases as completion on file name?  I believe that
with the new prompt change, that is unlikely.

>
>> As I noted in the bug, most of the completions that would be
>> provided by read-file-name-internal don't work
>
> IMO, that's okay, because wildcards cannot be meaningfully completed
> on.

But the aliases from grep-files-aliases can be meaningfully
completed.  I don't see why we shouldn't provide meaningful
completion if the user defines a lot of aliases, seeing as how
the current file name completion is useless.