bug#2585: 23.0.90; read-file-name with dialog

bug#2585: 23.0.90; read-file-name with dialog

[MJ]

When read-file-name is called and uses windows dialog to read a file
name, the 'dir' parameter has to be ended with '/'. It it does not,
the last part of the path name is used as the filename while the
default directory is the stripped 'dir' without last part. This does
not happen in Emacs 22. 

In minibuffer, there is comment that says: 

	;; If DIR contains a file name, split it.

I'm not sure if that is the right thing to do. At least, it breaks the
compatibility with previous Emacs version. 

Is this an intended change?

Thanks. 

--
In GNU Emacs 23.0.90.1 (i386-mingw-nt5.1.2600)
 of 2009-02-22 on T42
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (3.4) --cflags -I../../GnuWin32/include'

bug#2585: 23.0.90; read-file-name with dialog

[Jason Rumney]

Whoever did the conversion of read-file-name from C to lisp probably 
knows what was meant by this, by my naive impression is that the 
following logic is a mistake:

                  ;; If DIR contains a file name, split it.
                  (let ((file (file-name-nondirectory dir)))
                    (when (and default-filename (not (zerop (length file))))
                      (setq default-filename file)
                      (setq dir (file-name-directory dir)))


The third line makes more sense to me as:

         (when (and (not default-filename) (not (zerop (length file))))


ie. if default-filename is specified, then the splitting should NOT be done.

bug#2585: 23.0.90; read-file-name with dialog

[Chong Yidong]

> Whoever did the conversion of read-file-name from C to lisp probably 
> knows what was meant by this, by my naive impression is that the 
> following logic is a mistake:
>
>   ;; If DIR contains a file name, split it.
>   (let ((file (file-name-nondirectory dir)))
>     (when (and default-filename (not (zerop (length file))))
>       (setq default-filename file)
>       (setq dir (file-name-directory dir)))
>
> The third line makes more sense to me as:
>
>  (when (and (not default-filename) (not (zerop (length file))))
>
> ie. if default-filename is specified, then the splitting should NOT be
> done.

That seems right to me.  Stefan, you were the one who rewrote
read-file-name; could you verify this?

bug#2585: 23.0.90; read-file-name with dialog

[Stefan Monnier]

>> Whoever did the conversion of read-file-name from C to lisp probably 
>> knows what was meant by this, by my naive impression is that the 
>> following logic is a mistake:
>> 
>> ;; If DIR contains a file name, split it.
>> (let ((file (file-name-nondirectory dir)))
>> (when (and default-filename (not (zerop (length file))))
>> (setq default-filename file)
>> (setq dir (file-name-directory dir)))
>> 
>> The third line makes more sense to me as:
>> 
>> (when (and (not default-filename) (not (zerop (length file))))
>> 
>> ie. if default-filename is specified, then the splitting should NOT be
>> done.

> That seems right to me.  Stefan, you were the one who rewrote
> read-file-name; could you verify this?

Yes, it looks right,


        Stefan