bug#15386: 24.3; [Eshell] Second completion unsuccessful if equal to first

bug#15386: 24.3; [Eshell] Second completion unsuccessful if equal to first

[Joost Kremers]

This bug report will be sent to the Bug-GNU-Emacs mailing list
and the GNU bug tracker at debbugs.gnu.org.  Please check that
the From: line contains a valid email address.  After a delay of up
to one day, you should receive an acknowledgment at that address.

Please write in English if possible, as the Emacs maintainers
usually do not have translators for other languages.

Please describe exactly what actions triggered the bug, and
the precise symptoms of the bug.  If you can, give a recipe
starting from `emacs -Q':

==============================

Starting from `emacs -Q', Eshell cannot complete a directory if the
completion target is on the same line before it:

    $ ls ~/Dropbox/ ~/Dro

does not complete, even though there is a completion target. The
following *does* produce the correct completion:

    $ ls ~/Dropbox/Work/ ~/Dro

The following, however, does not:

    $ ls ~/Dropbox/ ~/Dropbox/Work/ ~/Dro


Thanks,

Joost Kremers



==============================


If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
For information about debugging Emacs, please read the file
/usr/share/emacs/24.3/etc/DEBUG.


In GNU Emacs 24.3.1 (i686-pc-linux-gnu, GTK+ Version 3.4.2)
 of 2013-08-22 on chindi02, modified by Debian
Windowing system distributor `The X.Org Foundation', version 11.0.11103000
System Description:	elementary OS Luna

Configured using:
 `configure '--build' 'i686-linux-gnu' '--build' 'i686-linux-gnu'
 '--prefix=/usr' '--sharedstatedir=/var/lib' '--libexecdir=/usr/lib'
 '--localstatedir=/var/lib' '--infodir=/usr/share/info'
 '--mandir=/usr/share/man' '--with-pop=yes'
 '--enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.3/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.3/site-lisp:/usr/share/emacs/site-lisp'
 '--with-crt-dir=/usr/lib/i386-linux-gnu' '--with-x=yes'
 '--with-x-toolkit=gtk3' '--with-toolkit-scroll-bars'
 'build_alias=i686-linux-gnu' 'CFLAGS=-g -O2 -fstack-protector
 --param=ssp-buffer-size=4 -Wformat -Wformat-security
 -Werror=format-security -Wall' 'LDFLAGS=-Wl,-Bsymbolic-functions
 -Wl,-z,relro' 'CPPFLAGS=-D_FORTIFY_SOURCE=2''

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: EShell

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
M-x e s h e l l <return> l s SPC ~ / d <backspace> 
D r o p <tab> SPC ~ / D r o <tab> M-x r e p o r t - 
e m c s <backspace> <backspace> c <backspace> a c <tab> 
<return>

Recent messages:
Loading em-cmpl...done
Loading em-dirs...done
Loading em-glob...done
Loading em-hist...done
Loading em-ls...done
Loading em-prompt...done
Loading em-script...done
Loading em-term...done
Loading em-unix...done
No completions of /home/joost/Dro

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util
mail-prsvr mail-utils em-unix pcomplete comint ansi-color em-term term
disp-table easymenu ehelp electric em-script em-prompt em-ls em-hist
em-pred em-glob em-dirs em-cmpl em-basic em-banner em-alias ring esh-var
esh-io esh-cmd esh-opt esh-ext esh-proc esh-arg eldoc help-fns
esh-groups eshell esh-module esh-mode esh-util time-date tooltip
ediff-hook vc-hooks lisp-float-type mwheel x-win x-dnd tool-bar dnd
fontset image regexp-opt fringe tabulated-list newcomment lisp-mode
register page menu-bar rfn-eshadow timer select scroll-bar mouse
jit-lock font-lock syntax facemenu font-core frame cham georgian
utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean
japanese hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese case-table epa-hook jka-cmpr-hook help simple abbrev
minibuffer loaddefs button faces cus-face macroexp files text-properties
overlay sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote make-network-process dbusbind
dynamic-setting system-font-setting font-render-setting move-toolbar gtk
x-toolkit x multi-tty emacs)

-- 
Joost Kremers
Life has its moments

bug#15386: 24.3; [Eshell] Second completion unsuccessful if equal to first

[Stefan Kangas]

Joost Kremers <joostkremers@fastmail.fm> writes:

> Starting from `emacs -Q', Eshell cannot complete a directory if the
> completion target is on the same line before it:
>
>     $ ls ~/Dropbox/ ~/Dro
>
> does not complete, even though there is a completion target. The
> following *does* produce the correct completion:
>
>     $ ls ~/Dropbox/Work/ ~/Dro
>
> The following, however, does not:
>
>     $ ls ~/Dropbox/ ~/Dropbox/Work/ ~/Dro

(This was reported 7 years ago but unfortunately never got a reply at
the time.)

I can reproduce this on current master, using emacs -Q.

bug#15386:

[Daniel Pettersson]

I don't believe this is a bug, but a feature as they say.

This behavior is controlled by `eshell-cmpl-use-paring'

> If t, pare alternatives that have already been used.
> If nil, you will always see the completion set of possible options, no
> matter which of those options have already been used in previous
> command arguments.

After setting the custom to a non-nil.

(setq eshell-cmpl-use-pairing nil)

Will turn on the desired behavior:
    $ ls ~/Dropbox/ ~/Dropb<Tab>
    $ ls ~/Dropbox/ ~/Dropbox/

bug#15386:

[Lars Ingebrigtsen]

Daniel Pettersson <daniel@dpettersson.net> writes:

> I don't believe this is a bug, but a feature as they say.
>
> This behavior is controlled by `eshell-cmpl-use-paring'
>
>> If t, pare alternatives that have already been used.
>> If nil, you will always see the completion set of possible options, no
>> matter which of those options have already been used in previous
>> command arguments.
>
> After setting the custom to a non-nil.
>
> (setq eshell-cmpl-use-pairing nil)
>
> Will turn on the desired behavior:
>     $ ls ~/Dropbox/ ~/Dropb<Tab>
>     $ ls ~/Dropbox/ ~/Dropbox/

Makes sense.  So since this is working as designed, I'm therefore
closing this bug report.