bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

[Ole Laursen]

Run emacs -Q, evaluate

  (icomplete-mode 1)
  (setq icomplete-show-matches-on-no-input t)

Make sure you have three buffers, e.g. by finding three files. Then
hit C-x b which should immediately show all buffers and use C-. or C-,
to select any other buffer than  what the modeline declares to be the
default, and hit C-j or RET.

Emacs then switches to the default buffer instead of the selected buffer.


Ole

bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

[Matthew Leach]

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Hello,

Ole Laursen <olau@iola.dk> writes:

> Run emacs -Q, evaluate
>
>   (icomplete-mode 1)
>   (setq icomplete-show-matches-on-no-input t)
>
> Make sure you have three buffers, e.g. by finding three files. Then
> hit C-x b which should immediately show all buffers and use C-. or C-,
> to select any other buffer than  what the modeline declares to be the
> default, and hit C-j or RET.
>
> Emacs then switches to the default buffer instead of the selected buffer.

I'm not sure if this is expected behaviour, since the "default" prompt
in the minibuffer doesn't disappear when cycling through results.
Nevertheless attached is a patch that fixes this.
-- 
Matt

lisp/ChangeLog:

2014-11-15  Matthew Leach  <matthew@mattleach.net>

	* minibuffer.el
	(completion-use-stored-completions-when-no-input): New.
	(completion--complete-and-exit): Use the above to decide whether
	to use the car of `completion-all-sorted-completions' as the
	candidate.

	* icomplete.el (icomplete-minibuffer-setup): set
	`completion-use-stored-completions-when-no-input' when
	`icomplete-show-matches-on-no-input' is t.


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diff --git a/lisp/icomplete.el b/lisp/icomplete.el
index 95a6e1b..dc90f0e 100644
--- a/lisp/icomplete.el
+++ b/lisp/icomplete.el
@@ -262,6 +262,7 @@ Usually run by inclusion in `minibuffer-setup-hook'."
     (add-hook 'post-command-hook #'icomplete-post-command-hook nil t)
     (run-hooks 'icomplete-minibuffer-setup-hook)
     (when icomplete-show-matches-on-no-input
+      (setq completion-use-stored-completions-when-no-input t)
       (icomplete-exhibit))))
 
 (defvar icomplete--in-region-buffer nil)
diff --git a/lisp/minibuffer.el b/lisp/minibuffer.el
index c9ce381..4ea0530 100644
--- a/lisp/minibuffer.el
+++ b/lisp/minibuffer.el
@@ -969,6 +969,7 @@ completion candidates than this number."
 (defvar-local completion-all-sorted-completions nil)
 (defvar-local completion--all-sorted-completions-location nil)
 (defvar completion-cycling nil)
+(defvar completion-use-stored-completions-when-no-input nil)
 
 (defvar completion-fail-discreetly nil
   "If non-nil, stay quiet when there  is no match.")
@@ -1332,8 +1333,15 @@ If `minibuffer-completion-confirm' is `confirm-after-completion',
 COMPLETION-FUNCTION is called if the current buffer's content does not
 appear to be a match."
     (cond
-     ;; Allow user to specify null string
-   ((= beg end) (funcall exit-function))
+     ;; Allow user to specify null string.  In the case that
+     ;; `completion-use-stored-completions-when-no-input' is t, use
+     ;; the car of `completion-all-sorted-completions' as the
+     ;; candidate.
+     ((= beg end)
+      (when completion-use-stored-completions-when-no-input
+        (completion--replace beg end (car completion-all-sorted-completions)))
+      (funcall exit-function))
+
      ((test-completion (buffer-substring beg end)
                        minibuffer-completion-table
                        minibuffer-completion-predicate)

bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

[Lars Ingebrigtsen]

Matthew Leach <matthew@mattleach.net> writes:

>> Run emacs -Q, evaluate
>>
>>   (icomplete-mode 1)
>>   (setq icomplete-show-matches-on-no-input t)
>>
>> Make sure you have three buffers, e.g. by finding three files. Then
>> hit C-x b which should immediately show all buffers and use C-. or C-,
>> to select any other buffer than  what the modeline declares to be the
>> default, and hit C-j or RET.
>>
>> Emacs then switches to the default buffer instead of the selected buffer.
>
> I'm not sure if this is expected behaviour, since the "default" prompt
> in the minibuffer doesn't disappear when cycling through results.
> Nevertheless attached is a patch that fixes this.

I've respun the patch for Emacs 28, and I think the new behaviour makes
a lot more sense than the old behaviour, which I couldn't understand the
point of at all.

But I'm not an icomplete user, so perhaps the old behaviour is what
people want?

This also has possible ramifications for other completion styles
(although only icomplete enables it with this patch), so I wonder
whether Stefan has any comments here?

diff --git a/lisp/icomplete.el b/lisp/icomplete.el
index 3747ae3d28..e3f7043e2c 100644
--- a/lisp/icomplete.el
+++ b/lisp/icomplete.el
@@ -432,6 +432,8 @@ icomplete-minibuffer-setup
     					 (current-local-map)))
     (add-hook 'pre-command-hook  #'icomplete-pre-command-hook  nil t)
     (add-hook 'post-command-hook #'icomplete-post-command-hook nil t)
+    (when icomplete-show-matches-on-no-input
+      (setq-local completion-use-stored-completions-when-no-input t))
     (run-hooks 'icomplete-minibuffer-setup-hook)))
 
 (defvar icomplete--in-region-buffer nil)
diff --git a/lisp/minibuffer.el b/lisp/minibuffer.el
index d2c3f9045e..c3e5440956 100644
--- a/lisp/minibuffer.el
+++ b/lisp/minibuffer.el
@@ -1126,6 +1126,7 @@ completion--cycle-threshold
 (defvar-local completion-all-sorted-completions nil)
 (defvar-local completion--all-sorted-completions-location nil)
 (defvar completion-cycling nil)      ;Function that takes down the cycling map.
+(defvar completion-use-stored-completions-when-no-input nil)
 
 (defvar completion-fail-discreetly nil
   "If non-nil, stay quiet when there  is no match.")
@@ -1510,8 +1511,15 @@ completion--complete-and-exit
 COMPLETION-FUNCTION is called if the current buffer's content does not
 appear to be a match."
     (cond
-     ;; Allow user to specify null string
-   ((= beg end) (funcall exit-function))
+     ;; Allow user to specify null string.  In the case that
+     ;; `completion-use-stored-completions-when-no-input' is t, use
+     ;; the car of `completion-all-sorted-completions' as the
+     ;; candidate.
+     ((= beg end)
+      (when completion-use-stored-completions-when-no-input
+        (completion--replace beg end (car completion-all-sorted-completions)))
+      (funcall exit-function))
+
      ((test-completion (buffer-substring beg end)
                        minibuffer-completion-table
                        minibuffer-completion-predicate)


-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

[Ole Laursen]

Thanks!

I'm a former iswitchb user, and this problem keeps me from switching
to icomplete (I'm currently on ido-switch-buffer), even though I would
like to have access to more advanced completion.


Ole

Den tor. 13. aug. 2020 kl. 11.34 skrev Lars Ingebrigtsen <larsi@gnus.org>:
>
> Matthew Leach <matthew@mattleach.net> writes:
>
> >> Run emacs -Q, evaluate
> >>
> >>   (icomplete-mode 1)
> >>   (setq icomplete-show-matches-on-no-input t)
> >>
> >> Make sure you have three buffers, e.g. by finding three files. Then
> >> hit C-x b which should immediately show all buffers and use C-. or C-,
> >> to select any other buffer than  what the modeline declares to be the
> >> default, and hit C-j or RET.
> >>
> >> Emacs then switches to the default buffer instead of the selected buffer.
> >
> > I'm not sure if this is expected behaviour, since the "default" prompt
> > in the minibuffer doesn't disappear when cycling through results.
> > Nevertheless attached is a patch that fixes this.
>
> I've respun the patch for Emacs 28, and I think the new behaviour makes
> a lot more sense than the old behaviour, which I couldn't understand the
> point of at all.
>
> But I'm not an icomplete user, so perhaps the old behaviour is what
> people want?
>
> This also has possible ramifications for other completion styles
> (although only icomplete enables it with this patch), so I wonder
> whether Stefan has any comments here?
>
> diff --git a/lisp/icomplete.el b/lisp/icomplete.el
> index 3747ae3d28..e3f7043e2c 100644
> --- a/lisp/icomplete.el
> +++ b/lisp/icomplete.el
> @@ -432,6 +432,8 @@ icomplete-minibuffer-setup
>                                          (current-local-map)))
>      (add-hook 'pre-command-hook  #'icomplete-pre-command-hook  nil t)
>      (add-hook 'post-command-hook #'icomplete-post-command-hook nil t)
> +    (when icomplete-show-matches-on-no-input
> +      (setq-local completion-use-stored-completions-when-no-input t))
>      (run-hooks 'icomplete-minibuffer-setup-hook)))
>
>  (defvar icomplete--in-region-buffer nil)
> diff --git a/lisp/minibuffer.el b/lisp/minibuffer.el
> index d2c3f9045e..c3e5440956 100644
> --- a/lisp/minibuffer.el
> +++ b/lisp/minibuffer.el
> @@ -1126,6 +1126,7 @@ completion--cycle-threshold
>  (defvar-local completion-all-sorted-completions nil)
>  (defvar-local completion--all-sorted-completions-location nil)
>  (defvar completion-cycling nil)      ;Function that takes down the cycling map.
> +(defvar completion-use-stored-completions-when-no-input nil)
>
>  (defvar completion-fail-discreetly nil
>    "If non-nil, stay quiet when there  is no match.")
> @@ -1510,8 +1511,15 @@ completion--complete-and-exit
>  COMPLETION-FUNCTION is called if the current buffer's content does not
>  appear to be a match."
>      (cond
> -     ;; Allow user to specify null string
> -   ((= beg end) (funcall exit-function))
> +     ;; Allow user to specify null string.  In the case that
> +     ;; `completion-use-stored-completions-when-no-input' is t, use
> +     ;; the car of `completion-all-sorted-completions' as the
> +     ;; candidate.
> +     ((= beg end)
> +      (when completion-use-stored-completions-when-no-input
> +        (completion--replace beg end (car completion-all-sorted-completions)))
> +      (funcall exit-function))
> +
>       ((test-completion (buffer-substring beg end)
>                         minibuffer-completion-table
>                         minibuffer-completion-predicate)
>
>
> --
> (domestic pets only, the antidote for overdose, milk.)
>    bloggy blog: http://lars.ingebrigtsen.no

bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

[Stefan Monnier]

> +(defvar completion-use-stored-completions-when-no-input nil)
>  (defvar completion-fail-discreetly nil
>    "If non-nil, stay quiet when there  is no match.")
> @@ -1510,8 +1511,15 @@ completion--complete-and-exit
>  COMPLETION-FUNCTION is called if the current buffer's content does not
>  appear to be a match."
>      (cond
> -     ;; Allow user to specify null string
> -   ((= beg end) (funcall exit-function))
> +     ;; Allow user to specify null string.  In the case that
> +     ;; `completion-use-stored-completions-when-no-input' is t, use
> +     ;; the car of `completion-all-sorted-completions' as the
> +     ;; candidate.
> +     ((= beg end)
> +      (when completion-use-stored-completions-when-no-input
> +        (completion--replace beg end (car completion-all-sorted-completions)))
> +      (funcall exit-function))

Would it be cleaner to have the following instead?

      ;; Allow user to specify null string.  Obey `completion-content-when-empty`.
      ((= beg end)
       (when completion-content-when-empty
         (completion--replace beg end completion-content-when-empty))
       (funcall exit-function))

So icomplete would be in charge of setting that var to the `car` of
`completion-all-sorted-completions`.


        Stefan

bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

[Lars Ingebrigtsen]

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

> Would it be cleaner to have the following instead?
>
>       ;; Allow user to specify null string.  Obey `completion-content-when-empty`.
>       ((= beg end)
>        (when completion-content-when-empty
>          (completion--replace beg end completion-content-when-empty))
>        (funcall exit-function))
>
> So icomplete would be in charge of setting that var to the `car` of
> `completion-all-sorted-completions`.

Yeah, that makes sense.  I'll take a stab at implementing it that way.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

[Lars Ingebrigtsen]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> Yeah, that makes sense.  I'll take a stab at implementing it that way.

I think I found where in the icomplete machinery to set this variable,
so I've now pushed this change.  It would be nice if others could test
this, too, and see whether it works.  :-)

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

[Ole Laursen]

I just built from trunk, and it now works! Flawless victory. :)

Thanks again to all involved!


Ole

Den fre. 14. aug. 2020 kl. 13.31 skrev Lars Ingebrigtsen <larsi@gnus.org>:
>
> Lars Ingebrigtsen <larsi@gnus.org> writes:
>
> > Yeah, that makes sense.  I'll take a stab at implementing it that way.
>
> I think I found where in the icomplete machinery to set this variable,
> so I've now pushed this change.  It would be nice if others could test
> this, too, and see whether it works.  :-)
>
> --
> (domestic pets only, the antidote for overdose, milk.)
>    bloggy blog: http://lars.ingebrigtsen.no

bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

[Lars Ingebrigtsen]

Ole Laursen <olau@iola.dk> writes:

> I just built from trunk, and it now works! Flawless victory. :)

Thanks for testing.  :-)

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#19032: 24.4; icomplete cannot select matches with C-x b with no input

[Matthew Leach]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> Lars Ingebrigtsen <larsi@gnus.org> writes:
>
>> Yeah, that makes sense.  I'll take a stab at implementing it 
>> that way.
>
> I think I found where in the icomplete machinery to set this 
> variable,
> so I've now pushed this change.  It would be nice if others 
> could test
> this, too, and see whether it works.  :-)

Thanks for fixing this Lars.  Much appreciated!
--
Matt