Stefan Monnier <monnier@iro.umontreal.ca> writes:

>>>> This inspired me to do something not exactly this but which also gets
>>>> rid of the new argument to create-file-buffer.  How about this:
>>>
>>> Now you're talking!  :-)
>>> LGTM!  Thank you very much,
>>
>> Great!  Here's that as a complete patch again.
>
> Eli, OK to install on `master`?
>
>
>         Stefan
>
>
> PS: Nitpicks:
>
>> +  (let* ((lastname (if (directory-name-p filename)
>> +                       (file-name-nondirectory (directory-file-name filename))
>> +                     (file-name-nondirectory filename)))
>
> Aka
>
>      (let* ((lastname (file-name-nondirectory
>                        (if (directory-name-p filename)
>                            (directory-file-name filename)
>                          filename)))
>
> or even just
>
>      (let* ((lastname (file-name-nondirectory
>                        (directory-file-name filename)))

Absolutely, makes sense.

>> +         (lastname (if (and (directory-name-p filename) uniquify-trailing-separator-p)
>> +                       (cond ((eq uniquify-buffer-name-style 'forward)
>> +	                      (file-name-as-directory lastname))
>> +	                     ((eq uniquify-buffer-name-style 'reverse)
>> +	                      (concat (or uniquify-separator "\\") lastname))
>> +                             (t lastname))
>> +                     lastname))
>
> Here you can merge the `if` into the `cond` and I'd test
> `uniquify-trailing-separator-p` first (cheaper and nil by default)

Yes, makes sense.  Revised patch for these two below.

> and since we know (directory-name-p filename), I'd be tempted to replace
> (file-name-as-directory lastname) with just `filename`.

(file-name-as-directory lastname) and filename are different though: the
former is only the last component of filename, but as a directory name.
The latter is the full filename, which is not what the basename of the
buffer should be.  (since it gets no further processing)

> Also I'd argue that when `uniquify-trailing-separator-p` and
> (directory-name-p filename) are both true we never want to use just
> `lastname` so the default should be to return `filename`:
>
>             (lastname (cond
>                        ((not (and uniquify-trailing-separator-p (directory-name-p filename)))
>                         lastname)
>                        ((eq uniquify-buffer-name-style 'reverse)
>                         (concat (or uniquify-separator "\\") lastname))
>                        (t filename)))
>
> so for `post-forward` (my personal favorite) /foo/bar/mumble/name/ would
> turn into name/|bar/mumble.
> WDYT?

I agree that would be good (modulo that it does need to be
(file-name-as-directory lastname) rather than filename), but it would
change the existing behavior and not comply with the docstring of
`uniquify-trailing-separator-p'.  (I think it would be a reasonable
change though, but probably as a subsequent change)