Wrong common substring highlighted in Completion buffer

Wrong common substring highlighted in Completion buffer

[Juri Linkov]

After typing `C-h f read-mini C-b C-b C-b C-b TAB' wrong common
substrings are highlighted in the *Completions* buffer.  The
substring "read-mini" is highlighted, but really completion is
performed on the substring "read-" before point in the minibuffer.

The function returning the right minibuffer substring is
minibuffer_completion_contents.  I believe the following patch
is correct.

Index: src/minibuf.c
===================================================================
RCS file: /cvsroot/emacs/emacs/src/minibuf.c,v
retrieving revision 1.294
diff -c -r1.294 minibuf.c
*** src/minibuf.c	6 Dec 2005 15:53:58 -0000	1.294
--- src/minibuf.c	10 Dec 2005 10:10:42 -0000
***************
*** 2563,2569 ****
  display_completion_list_1 (list)
       Lisp_Object list;
  {
!   return Fdisplay_completion_list (list, Qnil);
  }
  
  DEFUN ("minibuffer-completion-help", Fminibuffer_completion_help, Sminibuffer_completion_help,
--- 2565,2571 ----
  display_completion_list_1 (list)
       Lisp_Object list;
  {
!   return Fdisplay_completion_list (list, minibuffer_completion_contents ());
  }
  
  DEFUN ("minibuffer-completion-help", Fminibuffer_completion_help, Sminibuffer_completion_help,

-- 
Juri Linkov
http://www.jurta.org/emacs/

Re: Wrong common substring highlighted in Completion buffer

[Richard M. Stallman]

Thanks.  Please install your fix.

Re: Wrong common substring highlighted in Completion buffer

[Juri Linkov]

> Thanks.  Please install your fix.

This fix broke highlighting of file name completions (which didn't
work before anyway when point in not in the end of the minibuffer).
Since file completion is a special case, the following patch should
handle all cases of file name completions correctly.

Index: lisp/simple.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/simple.el,v
retrieving revision 1.778
diff -c -r1.778 simple.el
*** lisp/simple.el	10 Dec 2005 01:12:25 -0000	1.778
--- lisp/simple.el	12 Dec 2005 07:42:50 -0000
***************
*** 4901,4916 ****
  ;; after the text of the completion list buffer is written.
  (defun completion-setup-function ()
    (let* ((mainbuf (current-buffer))
!          (mbuf-contents (minibuffer-contents))
           (common-string-length (length mbuf-contents)))
      ;; When reading a file name in the minibuffer,
      ;; set default-directory in the minibuffer
--- 4901,4916 ----
  ;; after the text of the completion list buffer is written.
  (defun completion-setup-function ()
    (let* ((mainbuf (current-buffer))
!          (mbuf-contents (or completion-common-substring (minibuffer-contents)))
           (common-string-length (length mbuf-contents)))
      ;; When reading a file name in the minibuffer,
      ;; set default-directory in the minibuffer
***************
*** 4941,4947 ****
                  ;; the start of the last file name component.
  		(with-current-buffer mainbuf
  		  (save-excursion
- 		    (goto-char (point-max))
  		    (skip-chars-backward completion-root-regexp)
  		    (- (point) (minibuffer-prompt-end))))
                ;; Otherwise, in minibuffer, the whole input is being completed.
--- 4941,4946 ----
***************
*** 4960,4966 ****
        ;; Put faces on first uncommon characters and common parts.
        (when (or completion-common-substring completion-base-size)
          (setq common-string-length
!               (if completion-common-substring
                    (length completion-common-substring)
                  (- common-string-length completion-base-size)))
  	(let ((element-start (point-min))
--- 4959,4966 ----
        ;; Put faces on first uncommon characters and common parts.
        (when (or completion-common-substring completion-base-size)
          (setq common-string-length
!               (if (and completion-common-substring
! 		       (not minibuffer-completing-file-name))
                    (length completion-common-substring)
                  (- common-string-length completion-base-size)))
  	(let ((element-start (point-min))

-- 
Juri Linkov
http://www.jurta.org/emacs/

Re: Wrong common substring highlighted in Completion buffer

[Juri Linkov]

I also noticed that after using M-TAB in a Lisp buffer and selecting
a completion from the *Completion* buffer, highlighting from the
common substring is copied to the original buffer.  This can be fixed
by the following patch.

Index: lisp/simple.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/simple.el,v
retrieving revision 1.778
diff -c -r1.778 simple.el
*** lisp/simple.el	10 Dec 2005 01:12:25 -0000	1.778
--- lisp/simple.el	12 Dec 2005 07:43:55 -0000
***************
*** 4744,4750 ****
  	(error "No completion here"))
      (setq beg (previous-single-property-change beg 'mouse-face))
      (setq end (or (next-single-property-change end 'mouse-face) (point-max)))
!     (setq completion (buffer-substring beg end))
      (let ((owindow (selected-window)))
        (if (and (one-window-p t 'selected-frame)
  	       (window-dedicated-p (selected-window)))
--- 4744,4750 ----
  	(error "No completion here"))
      (setq beg (previous-single-property-change beg 'mouse-face))
      (setq end (or (next-single-property-change end 'mouse-face) (point-max)))
!     (setq completion (buffer-substring-no-properties beg end))
      (let ((owindow (selected-window)))
        (if (and (one-window-p t 'selected-frame)
  	       (window-dedicated-p (selected-window)))

-- 
Juri Linkov
http://www.jurta.org/emacs/

Re: Wrong common substring highlighted in Completion buffer

[Richard M. Stallman]

If your fix needs fixing, please just do it.

Re: Wrong common substring highlighted in Completion buffer

[Juri Linkov]

> If your fix needs fixing, please just do it.

I hesitated to install this fix, because I felt this is not the right thing.
Now I've completely reworked the function completion-setup-function and some
related functions to make highlighting of common strings correct in many cases:

* in normal minibuffer completion and in file name minibuffer completion;

* for both above cases if point is at the end of the minibuffer and
  if point is in the middle of the minibuffer;

* for partial-completion-mode with combinations of all cases above
  and with leading `-';

* for Info node/file completion (which uses completion-base-size-function);

* for crm-minibuffer-completion (which reads multiple strings with completion).


In the patch below the following changes were made:

* Revert the change in display_completion_list_1 that explicitly
uses minibuffer_completion_contents.  Use nil as before.

* Make the function minibuffer_completion_contents available to Lisp.
Its Lisp name is minibuffer-completion-contents.

* Use this function in completion-setup-function to get the correct
completion part of the minibuffer.

* Due to using this function in completion-setup-function,
partial-completion-mode doesn't need to set the argument common-substring
for display-completion-list.  Completion-setup-function now does the
right thing for it.

There was one inconsistency in partial-completion-mode that needed
special handling in completion-setup-function.  I tracked it down to
the dubious condition in `PC-do-completion': (equal (point) beg).

This condition prevented point to be placed at the first different
character in the minibuffer (as normal completion does) *if* this
position is at the beginning of the minibuffer.  After removing this
condition this works consistently for the case of completions like
`-function'.  It puts point before `-function' and highlights the
first character of available completions in the *Completions* buffer.
So this change also removes the need for special handling
of partial-completion-mode in completion-setup-function.

* Another FIXME in completion-setup-function was saying about the need
of an extra argument for completion-base-size-function.  I replaced it
with the advice to use the global value of completion-common-substring
or directly the contents of the minibuffer in a function called via
completion-base-size-function.  Also I changed the lambda on
Info-read-node-name-1 to match `(' on the global value of
completion-common-substring or (minibuffer-completion-contents).

Index: src/minibuf.c
===================================================================
RCS file: /sources/emacs/emacs/src/minibuf.c,v
retrieving revision 1.295
diff -c -r1.295 minibuf.c
*** src/minibuf.c	11 Dec 2005 09:50:53 -0000	1.295
--- src/minibuf.c	14 Dec 2005 07:57:15 -0000
***************
*** 388,393 ****
--- 388,406 ----
    return make_buffer_string (prompt_end, ZV, 0);
  }
  
+ DEFUN ("minibuffer-completion-contents", Fminibuffer_completion_contents,
+        Sminibuffer_completion_contents, 0, 0, 0,
+        doc: /* Return the user input in a minibuffer before point as a string.
+ That is what completion commands operate on.
+ The current buffer must be a minibuffer.  */)
+      ()
+ {
+   int prompt_end = XINT (Fminibuffer_prompt_end ());
+   if (PT < prompt_end)
+     error ("Cannot do completion in the prompt");
+   return make_buffer_string (prompt_end, PT, 1);
+ }
+ 
  DEFUN ("delete-minibuffer-contents", Fdelete_minibuffer_contents,
         Sdelete_minibuffer_contents, 0, 0, 0,
         doc: /* Delete all user input in a minibuffer.
***************
*** 400,416 ****
    return Qnil;
  }
  
- /* Get the text in the minibuffer before point.
-    That is what completion commands operate on.  */
- 
- Lisp_Object
- minibuffer_completion_contents ()
- {
-   int prompt_end = XINT (Fminibuffer_prompt_end ());
-   if (PT < prompt_end)
-     error ("Cannot do completion in the prompt");
-   return make_buffer_string (prompt_end, PT, 1);
- }
  \f
  /* Read from the minibuffer using keymap MAP and initial contents INITIAL,
     putting point minus BACKUP_N bytes from the end of INITIAL,
--- 413,418 ----
***************
*** 1899,1905 ****
    Lisp_Object last;
    struct gcpro gcpro1, gcpro2;
  
!   completion = Ftry_completion (minibuffer_completion_contents (),
  				Vminibuffer_completion_table,
  				Vminibuffer_completion_predicate);
    last = last_exact_completion;
--- 1904,1910 ----
    Lisp_Object last;
    struct gcpro gcpro1, gcpro2;
  
!   completion = Ftry_completion (Fminibuffer_completion_contents (),
  				Vminibuffer_completion_table,
  				Vminibuffer_completion_predicate);
    last = last_exact_completion;
***************
*** 1921,1927 ****
        return 1;
      }
  
!   string = minibuffer_completion_contents ();
  
    /* COMPLETEDP should be true if some completion was done, which
       doesn't include simply changing the case of the entered string.
--- 1926,1932 ----
        return 1;
      }
  
!   string = Fminibuffer_completion_contents ();
  
    /* COMPLETEDP should be true if some completion was done, which
       doesn't include simply changing the case of the entered string.
***************
*** 1988,1994 ****
    last_exact_completion = completion;
    if (!NILP (last))
      {
!       tem = minibuffer_completion_contents ();
        if (!NILP (Fequal (tem, last)))
  	Fminibuffer_completion_help ();
      }
--- 1993,1999 ----
    last_exact_completion = completion;
    if (!NILP (last))
      {
!       tem = Fminibuffer_completion_contents ();
        if (!NILP (Fequal (tem, last)))
  	Fminibuffer_completion_help ();
      }
***************
*** 2191,2197 ****
    /* We keep calling Fbuffer_string rather than arrange for GC to
       hold onto a pointer to one of the strings thus made.  */
  
!   completion = Ftry_completion (minibuffer_completion_contents (),
  				Vminibuffer_completion_table,
  				Vminibuffer_completion_predicate);
    if (NILP (completion))
--- 2196,2202 ----
    /* We keep calling Fbuffer_string rather than arrange for GC to
       hold onto a pointer to one of the strings thus made.  */
  
!   completion = Ftry_completion (Fminibuffer_completion_contents (),
  				Vminibuffer_completion_table,
  				Vminibuffer_completion_predicate);
    if (NILP (completion))
***************
*** 2223,2229 ****
      int buffer_nchars, completion_nchars;
  
      CHECK_STRING (completion);
!     tem = minibuffer_completion_contents ();
      GCPRO2 (completion, tem);
      /* If reading a file name,
         expand any $ENVVAR refs in the buffer and in TEM.  */
--- 2228,2234 ----
      int buffer_nchars, completion_nchars;
  
      CHECK_STRING (completion);
!     tem = Fminibuffer_completion_contents ();
      GCPRO2 (completion, tem);
      /* If reading a file name,
         expand any $ENVVAR refs in the buffer and in TEM.  */
***************
*** 2287,2293 ****
    if (i == SCHARS (completion))
      {
        GCPRO1 (completion);
!       tem = Ftry_completion (concat2 (minibuffer_completion_contents (),
  				      build_string (" ")),
  			     Vminibuffer_completion_table,
  			     Vminibuffer_completion_predicate);
--- 2292,2298 ----
    if (i == SCHARS (completion))
      {
        GCPRO1 (completion);
!       tem = Ftry_completion (concat2 (Fminibuffer_completion_contents (),
  				      build_string (" ")),
  			     Vminibuffer_completion_table,
  			     Vminibuffer_completion_predicate);
***************
*** 2299,2305 ****
  	{
  	  GCPRO1 (completion);
  	  tem =
! 	    Ftry_completion (concat2 (minibuffer_completion_contents (),
  				      build_string ("-")),
  			     Vminibuffer_completion_table,
  			     Vminibuffer_completion_predicate);
--- 2304,2310 ----
  	{
  	  GCPRO1 (completion);
  	  tem =
! 	    Ftry_completion (concat2 (Fminibuffer_completion_contents (),
  				      build_string ("-")),
  			     Vminibuffer_completion_table,
  			     Vminibuffer_completion_predicate);
***************
*** 2371,2378 ****
  It is used to put faces, `completions-first-difference' and
  `completions-common-part' on the completion buffer. The
  `completions-common-part' face is put on the common substring
! specified by COMMON-SUBSTRING. If COMMON-SUBSTRING is nil,
! the faces are not put.
  Internally, COMMON-SUBSTRING is bound to `completion-common-substring'
  during running `completion-setup-hook'. */)
       (completions, common_substring)
--- 2376,2383 ----
  It is used to put faces, `completions-first-difference' and
  `completions-common-part' on the completion buffer. The
  `completions-common-part' face is put on the common substring
! specified by COMMON-SUBSTRING. If COMMON-SUBSTRING is nil
! and the current buffer is not the minibuffer, the faces are not put.
  Internally, COMMON-SUBSTRING is bound to `completion-common-substring'
  during running `completion-setup-hook'. */)
       (completions, common_substring)
***************
*** 2563,2569 ****
  display_completion_list_1 (list)
       Lisp_Object list;
  {
!   return Fdisplay_completion_list (list, minibuffer_completion_contents ());
  }
  
  DEFUN ("minibuffer-completion-help", Fminibuffer_completion_help, Sminibuffer_completion_help,
--- 2568,2574 ----
  display_completion_list_1 (list)
       Lisp_Object list;
  {
!   return Fdisplay_completion_list (list, Qnil);
  }
  
  DEFUN ("minibuffer-completion-help", Fminibuffer_completion_help, Sminibuffer_completion_help,
***************
*** 2574,2580 ****
    Lisp_Object completions;
  
    message ("Making completion list...");
!   completions = Fall_completions (minibuffer_completion_contents (),
  				  Vminibuffer_completion_table,
  				  Vminibuffer_completion_predicate,
  				  Qt);
--- 2579,2585 ----
    Lisp_Object completions;
  
    message ("Making completion list...");
!   completions = Fall_completions (Fminibuffer_completion_contents (),
  				  Vminibuffer_completion_table,
  				  Vminibuffer_completion_predicate,
  				  Qt);
***************
*** 2883,2888 ****
--- 2888,2894 ----
    defsubr (&Sminibuffer_prompt_end);
    defsubr (&Sminibuffer_contents);
    defsubr (&Sminibuffer_contents_no_properties);
+   defsubr (&Sminibuffer_completion_contents);
    defsubr (&Sdelete_minibuffer_contents);
  
    defsubr (&Stry_completion);

Index: lisp/simple.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/simple.el,v
retrieving revision 1.778
diff -c -r1.778 simple.el
*** lisp/simple.el	10 Dec 2005 01:12:25 -0000	1.778
--- lisp/simple.el	14 Dec 2005 07:57:45 -0000
***************
*** 4901,4968 ****
    "Common prefix substring to use in `completion-setup-function' to put faces.
  The value is set by `display-completion-list' during running `completion-setup-hook'.
  
! To put faces, `completions-first-difference' and `completions-common-part'
! into \"*Completions*\* buffer, the common prefix substring in completions is
! needed as a hint. (Minibuffer is a special case. The content of minibuffer itself
! is the substring.)")
  
  ;; This function goes in completion-setup-hook, so that it is called
  ;; after the text of the completion list buffer is written.
  (defun completion-setup-function ()
    (let* ((mainbuf (current-buffer))
!          (mbuf-contents (minibuffer-contents))
!          (common-string-length (length mbuf-contents)))
      ;; When reading a file name in the minibuffer,
      ;; set default-directory in the minibuffer
      ;; so it will get copied into the completion list buffer.
!     (if minibuffer-completing-file-name
  	(with-current-buffer mainbuf
  	  (setq default-directory (file-name-directory mbuf-contents))))
-     ;; If partial-completion-mode is on, point might not be after the
-     ;; last character in the minibuffer.
-     ;; FIXME: This hack should be moved to complete.el where we call
-     ;; display-completion-list.
-     (when partial-completion-mode
-       (setq common-string-length
-             (if (eq (char-after (field-beginning)) ?-)
-                 ;; If the text to be completed starts with a `-', there is no
-                 ;; common prefix.
-                 ;; FIXME: this probably still doesn't do the right thing
-                 ;; when completing file names.  It's not even clear what
-                 ;; is TRT.
-                 0
-               (- common-string-length (- (point-max) (point))))))
      (with-current-buffer standard-output
        (completion-list-mode)
        (set (make-local-variable 'completion-reference-buffer) mainbuf)
!       (setq completion-base-size
!             (if minibuffer-completing-file-name
!                 ;; For file name completion, use the number of chars before
!                 ;; the start of the last file name component.
! 		(with-current-buffer mainbuf
! 		  (save-excursion
! 		    (goto-char (point-max))
! 		    (skip-chars-backward completion-root-regexp)
! 		    (- (point) (minibuffer-prompt-end))))
!               ;; Otherwise, in minibuffer, the whole input is being completed.
!               (if (minibufferp mainbuf) 0)))
!       (if (and (symbolp minibuffer-completion-table)
!                (get minibuffer-completion-table 'completion-base-size-function))
!           (setq completion-base-size
!                 ;; FIXME: without any extra arg, how is this function
!                 ;; expected to return anything else than a constant unless
!                 ;; it redoes part of the work of all-completions?
!                 ;; In most cases this value would better be computed and
!                 ;; returned at the same time as the list of all-completions
!                 ;; is computed.  --Stef
!                 (funcall (get minibuffer-completion-table
!                               'completion-base-size-function))))
        ;; Put faces on first uncommon characters and common parts.
!       (when (or completion-common-substring completion-base-size)
!         (setq common-string-length
!               (if completion-common-substring
!                   (length completion-common-substring)
!                 (- common-string-length completion-base-size)))
  	(let ((element-start (point-min))
                (maxp (point-max))
                element-common-end)
--- 4958,5011 ----
    "Common prefix substring to use in `completion-setup-function' to put faces.
  The value is set by `display-completion-list' during running `completion-setup-hook'.
  
! To put faces `completions-first-difference' and `completions-common-part'
! in the *Completions* buffer, the common prefix substring in completions
! is needed as a hint.  (The minibuffer is a special case.  The content
! of the minibuffer before point is always the common substring.)")
  
  ;; This function goes in completion-setup-hook, so that it is called
  ;; after the text of the completion list buffer is written.
  (defun completion-setup-function ()
    (let* ((mainbuf (current-buffer))
!          (mbuf-contents (and (minibufferp mainbuf)
! 			     (minibuffer-completion-contents)))
! 	 (common-substring (or completion-common-substring mbuf-contents))
!          common-string-length)
      ;; When reading a file name in the minibuffer,
      ;; set default-directory in the minibuffer
      ;; so it will get copied into the completion list buffer.
!     (if (and minibuffer-completing-file-name mbuf-contents)
  	(with-current-buffer mainbuf
  	  (setq default-directory (file-name-directory mbuf-contents))))
      (with-current-buffer standard-output
        (completion-list-mode)
        (set (make-local-variable 'completion-reference-buffer) mainbuf)
!       (if mbuf-contents
! 	  (setq completion-base-size
! 		(cond
! 		 ((and (symbolp minibuffer-completion-table)
! 		       (get minibuffer-completion-table 'completion-base-size-function))
! 		  ;; To compute base size, this function can use the global value
! 		  ;; of completion-common-substring or directly the contents of
! 		  ;; the minibuffer.
! 		  (with-current-buffer mainbuf
! 		    (funcall (get minibuffer-completion-table
! 				  'completion-base-size-function))))
! 		 (minibuffer-completing-file-name
! 		  ;; For file name completion, use the number of chars before
! 		  ;; the start of the file name component at point.
! 		  (with-current-buffer mainbuf
! 		    (save-excursion
! 		      (skip-chars-backward completion-root-regexp)
! 		      (- (point) (minibuffer-prompt-end))))))))
!       (setq common-string-length
! 	    (- (length common-substring)
! 	       (if (and (integerp completion-base-size)
! 			(> completion-base-size 0))
! 		   completion-base-size
! 		 0)))
        ;; Put faces on first uncommon characters and common parts.
!       (when (and (integerp common-string-length) (>= common-string-length 0))
  	(let ((element-start (point-min))
                (maxp (point-max))
                element-common-end)

Index: lisp/complete.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/complete.el,v
retrieving revision 1.47
diff -c -r1.47 complete.el
*** lisp/complete.el	27 Nov 2005 20:53:55 -0000	1.47
--- lisp/complete.el	14 Dec 2005 07:55:34 -0000
***************
*** 613,620 ****
  				    (insert (substring prefix i (1+ i)))
  				    (setq end (1+ end)))
  				  (setq i (1+ i)))
! 				(or pt (equal (point) beg)
! 				    (setq pt (point)))
  				(looking-at PC-delim-regex))
  			      (setq skip (concat skip
  						 (regexp-quote prefix)
--- 613,619 ----
  				    (insert (substring prefix i (1+ i)))
  				    (setq end (1+ end)))
  				  (setq i (1+ i)))
! 				(or pt (setq pt (point)))
  				(looking-at PC-delim-regex))
  			      (setq skip (concat skip
  						 (regexp-quote prefix)

Index: lisp/info.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/info.el,v
retrieving revision 1.467
diff -c -r1.467 info.el
*** lisp/info.el	12 Dec 2005 05:15:53 -0000	1.467
--- lisp/info.el	14 Dec 2005 07:54:54 -0000
***************
*** 1517,1523 ****
  
  ;; Arrange to highlight the proper letters in the completion list buffer.
  (put 'Info-read-node-name-1 'completion-base-size-function
!      (lambda () 1))
  
  (defun Info-read-node-name (prompt &optional default)
    (let* ((completion-ignore-case t)
--- 1523,1533 ----
  
  ;; Arrange to highlight the proper letters in the completion list buffer.
  (put 'Info-read-node-name-1 'completion-base-size-function
!      (lambda ()
!        (if (string-match "\\`([^)]*\\'"
! 			 (or completion-common-substring
! 			     (minibuffer-completion-contents)))
! 	   1)))
  
  (defun Info-read-node-name (prompt &optional default)
    (let* ((completion-ignore-case t)

Index: lisp/emacs-lisp/crm.el
===================================================================
RCS file: /sources/emacs/emacs/lisp/emacs-lisp/crm.el,v
retrieving revision 1.9
diff -c -r1.9 crm.el
*** lisp/emacs-lisp/crm.el	6 Aug 2005 17:08:59 -0000	1.9
--- lisp/emacs-lisp/crm.el	14 Dec 2005 07:52:34 -0000
***************
*** 234,240 ****
  	t
        nil)))
  
! (defun crm-minibuffer-completion-help ()
    "Display a list of possible completions of the current minibuffer element."
    (interactive)
    (message "Making completion list...")
--- 234,240 ----
  	t
        nil)))
  
! (defun crm-minibuffer-completion-help (&optional common-substring)
    "Display a list of possible completions of the current minibuffer element."
    (interactive)
    (message "Making completion list...")
***************
*** 247,253 ****
        (if (null completions)
  	  (crm-temp-echo-area-glyphs " [No completions]")
  	(with-output-to-temp-buffer "*Completions*"
! 	  (display-completion-list (sort completions 'string-lessp))))))
    nil)
  
  (defun crm-do-completion ()
--- 247,255 ----
        (if (null completions)
  	  (crm-temp-echo-area-glyphs " [No completions]")
  	(with-output-to-temp-buffer "*Completions*"
! 	  (display-completion-list
! 	   (sort completions 'string-lessp)
! 	   common-substring)))))
    nil)
  
  (defun crm-do-completion ()
***************
*** 303,309 ****
  	      (if completedp ; some completion happened
  		  (throw 'crm-exit 5)
  		(if completion-auto-help
! 		    (crm-minibuffer-completion-help)
  		  (crm-temp-echo-area-glyphs " [Next char not unique]")))
  	      (throw 'crm-exit 6))
  	  (if completedp
--- 305,311 ----
  	      (if completedp ; some completion happened
  		  (throw 'crm-exit 5)
  		(if completion-auto-help
! 		    (crm-minibuffer-completion-help crm-current-element)
  		  (crm-temp-echo-area-glyphs " [Next char not unique]")))
  	      (throw 'crm-exit 6))
  	  (if completedp
***************
*** 313,319 ****
  	(if (not (null last))
  	    (progn
  	      (if (not (null (equal crm-current-element last)))
! 		  (crm-minibuffer-completion-help))))
  
  	;; returning -- was already an exact completion
  	(throw 'crm-exit 3)))))
--- 315,321 ----
  	(if (not (null last))
  	    (progn
  	      (if (not (null (equal crm-current-element last)))
! 		  (crm-minibuffer-completion-help crm-current-element))))
  
  	;; returning -- was already an exact completion
  	(throw 'crm-exit 3)))))

-- 
Juri Linkov
http://www.jurta.org/emacs/

Re: Wrong common substring highlighted in Completion buffer

[Richard M. Stallman]

Thanks for working on this.  Could you write a news entry
for minibuffer-completion-contents, and update the Lisp manual?