bug#51650: Autocomplete: first Tab should show *Completions* buffer

[Carlos Pita]

Hi all,

I might be wrong here, but I believe find-file and friends work in a
way that is a bit inconvenient as well as a bit inconsistent.

For example:

1. I press C-x C-f and get "Find file: ~/"
2. I press Tab once and get the message "Complete, but not unique"
3. I press Tab again and the *Completions* buffer appears with
candidate completions.
4. I type "Desk" and press Tab.
5. Now I'm at ~/Desktop/ and press Tab again.
6. I get the message "Complete, but not unique" but at the same time
the *Completions* buffer is displayed.

Now, this is inconvenient since the first time I have to type Tab twice
in order to get the *Completions* buffer (or ?, which is not very
handy in most keyboards). AFAICS the first Tab does nothing at all
except in the rare situation when there is a single completion, in
other cases the inference that the user could use some help seems not
too far-fetched to me.

And this also might be seen as inconsistent in that the second time
the same Tab shows both the "not unique" message and the help buffer,
which is IMO a more sensible behavior.

I think that Tab in step 2 should show the message and the list of
possible completions at the same time.

What do you think?

Best regards,
Carlos