bug#62592: Not creating new Tabs with small window

bug#62592: Not creating new Tabs with small window

[Claudio Grondi]

1. ~ $ emacs -Q
2. Menu -> Options -> Show/Hide -> Tab Bar (gives Tab*scratch*)
3. resize the Emacs window to a small one, but large enough to show some Tab labels
3. 1x click on rightmost * in the Tab Bar to create a new Tab

The bug: No new Tab will be created and the minibuf and*Messages*  show:

    split-window: Window #<window 3 on*Messages*> too small for splitting

To: bug-gnu-emacs@gnu.org

Subject: 29.0.60; Not creating new Tabs with small window
--text follows this line--



In GNU Emacs 29.0.60 (build 1, x86_64-pc-linux-gnu, X toolkit, cairo
  version 1.16.0, Xaw3d scroll bars) of 2023-03-30 built on OoO
Repository revision: 4508a024e81834cfb01c6f7984182e1a6cbb91ea
Repository branch: emacs-29
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bug#62592: Not creating new Tabs with small window

[Juri Linkov]

> 1. ~ $ emacs -Q
> 2. Menu -> Options -> Show/Hide -> Tab Bar (gives Tab*scratch*)
> 3. resize the Emacs window to a small one, but large enough to show some Tab labels
> 3. 1x click on rightmost * in the Tab Bar to create a new Tab
>
> The bug: No new Tab will be created and the minibuf and*Messages*  show:
>
>    split-window: Window #<window 3 on*Messages*> too small for splitting

Thanks for the bug report.  It is related to bug#62427 where
we need to find a way to create a new window without using
delete-windows and split-window.

bug#62592: Not creating new Tabs with small window

[Juri Linkov]

[-- Attachment #1: Type: text/plain, Size: 751 bytes --]

>> 1. ~ $ emacs -Q
>> 2. Menu -> Options -> Show/Hide -> Tab Bar (gives Tab*scratch*)
>> 3. resize the Emacs window to a small one, but large enough to show some Tab labels
>> 3. 1x click on rightmost * in the Tab Bar to create a new Tab
>>
>> The bug: No new Tab will be created and the minibuf and*Messages*  show:
>>
>>    split-window: Window #<window 3 on*Messages*> too small for splitting
>
> Thanks for the bug report.  It is related to bug#62427 where
> we need to find a way to create a new window without using
> delete-windows and split-window.

Oh, I noticed the same problem in window-state-put too :-(
Restoring window states fails with the same error in narrow windows.
However, here is a fix.  Eli, is it ok to fix this in emacs-29?


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: split-window-window-min-height.patch --]
[-- Type: text/x-diff, Size: 1132 bytes --]

diff --git a/lisp/tab-bar.el b/lisp/tab-bar.el
index 35474e1c674..08f904ec73d 100644
--- a/lisp/tab-bar.el
+++ b/lisp/tab-bar.el
@@ -1586,7 +1595,8 @@ tab-bar-new-tab-to
               (window-state-put (window-state-get))
             ;; Create a new window to get rid of old window parameters
             ;; (e.g. prev/next buffers) of old window.
-            (split-window) (delete-window))))
+            (let ((window-min-height 1)) (split-window))
+            (delete-window))))
 
       (let ((buffer
              (if (and (functionp tab-bar-new-tab-choice)
diff --git a/lisp/window.el b/lisp/window.el
index aa7520f30fa..b2ee869940a 100644
--- a/lisp/window.el
+++ b/lisp/window.el
@@ -6391,7 +6396,8 @@ window-state-put
                      (selected-window)))
       (delete-other-windows-internal window root)
       ;; Create a new window to replace the existing one.
-      (setq window (prog1 (split-window window)
+      (setq window (prog1 (let ((window-min-height 1))
+                            (split-window window))
                      (delete-window window)))))
 
   (set-window-dedicated-p window nil)

bug#62592: Not creating new Tabs with small window

[Eli Zaretskii]

> Cc: 62592@debbugs.gnu.org
> From: Juri Linkov <juri@linkov.net>
> Date: Sun, 02 Apr 2023 20:49:09 +0300
> 
> >> 1. ~ $ emacs -Q
> >> 2. Menu -> Options -> Show/Hide -> Tab Bar (gives Tab*scratch*)
> >> 3. resize the Emacs window to a small one, but large enough to show some Tab labels
> >> 3. 1x click on rightmost * in the Tab Bar to create a new Tab
> >>
> >> The bug: No new Tab will be created and the minibuf and*Messages*  show:
> >>
> >>    split-window: Window #<window 3 on*Messages*> too small for splitting
> >
> > Thanks for the bug report.  It is related to bug#62427 where
> > we need to find a way to create a new window without using
> > delete-windows and split-window.
> 
> Oh, I noticed the same problem in window-state-put too :-(
> Restoring window states fails with the same error in narrow windows.
> However, here is a fix.  Eli, is it ok to fix this in emacs-29?

Yes, although I cannot say I'm fond of such kludges.

(I thought Benson Chu was working on a better fix for these problems?)

bug#62592: Not creating new Tabs with small window

[Juri Linkov]

>> >> 1. ~ $ emacs -Q
>> >> 2. Menu -> Options -> Show/Hide -> Tab Bar (gives Tab*scratch*)
>> >> 3. resize the Emacs window to a small one, but large enough to show some Tab labels
>> >> 3. 1x click on rightmost * in the Tab Bar to create a new Tab
>> >>
>> >> The bug: No new Tab will be created and the minibuf and*Messages*  show:
>> >>
>> >>    split-window: Window #<window 3 on*Messages*> too small for splitting
>> >
>> > Thanks for the bug report.  It is related to bug#62427 where
>> > we need to find a way to create a new window without using
>> > delete-windows and split-window.
>>
>> Oh, I noticed the same problem in window-state-put too :-(
>> Restoring window states fails with the same error in narrow windows.
>> However, here is a fix.  Eli, is it ok to fix this in emacs-29?
>
> Yes, although I cannot say I'm fond of such kludges.
>
> (I thought Benson Chu was working on a better fix for these problems?)

After bug#62427 was closed, this bug is still reproducible.
The proposed patch remains the same.

bug#62592: Not creating new Tabs with small window

[Juri Linkov]

>>> 1. ~ $ emacs -Q
>>> 2. Menu -> Options -> Show/Hide -> Tab Bar (gives Tab *scratch*)
>>> 3. resize the Emacs window to a small one, but large enough to show some Tab labels
>>> 3. 1x click on rightmost * in the Tab Bar to create a new Tab
>>>
>>> The bug: No new Tab will be created and the minibuf and*Messages*  show:
>>>
>>>    split-window: Window #<window 3 on*Messages*> too small for splitting
>>
>> Thanks for the bug report.  It is related to bug#62427 where
>> we need to find a way to create a new window without using
>> delete-windows and split-window.

The patch below still fails when the height of the window is 1 line.

Maybe Martin could help?

> diff --git a/lisp/tab-bar.el b/lisp/tab-bar.el
> index 35474e1c674..08f904ec73d 100644
> --- a/lisp/tab-bar.el
> +++ b/lisp/tab-bar.el
> @@ -1586,7 +1595,8 @@ tab-bar-new-tab-to
>                (window-state-put (window-state-get))
>              ;; Create a new window to get rid of old window parameters
>              ;; (e.g. prev/next buffers) of old window.
> -            (split-window) (delete-window))))
> +            (let ((window-min-height 1)) (split-window))
> +            (delete-window))))
>  
>        (let ((buffer
>               (if (and (functionp tab-bar-new-tab-choice)
> diff --git a/lisp/window.el b/lisp/window.el
> index aa7520f30fa..b2ee869940a 100644
> --- a/lisp/window.el
> +++ b/lisp/window.el
> @@ -6391,7 +6396,8 @@ window-state-put
>                       (selected-window)))
>        (delete-other-windows-internal window root)
>        ;; Create a new window to replace the existing one.
> -      (setq window (prog1 (split-window window)
> +      (setq window (prog1 (let ((window-min-height 1))
> +                            (split-window window))
>                       (delete-window window)))))
>  
>    (set-window-dedicated-p window nil)

bug#62592: Not creating new Tabs with small window

[martin rudalics]

 >>>> 1. ~ $ emacs -Q
 >>>> 2. Menu -> Options -> Show/Hide -> Tab Bar (gives Tab *scratch*)
 >>>> 3. resize the Emacs window to a small one, but large enough to show some Tab labels
 >>>> 3. 1x click on rightmost * in the Tab Bar to create a new Tab
 >>>>
 >>>> The bug: No new Tab will be created and the minibuf and*Messages*  show:
 >>>>
 >>>>     split-window: Window #<window 3 on*Messages*> too small for splitting
 >>>
 >>> Thanks for the bug report.  It is related to bug#62427 where
 >>> we need to find a way to create a new window without using
 >>> delete-windows and split-window.
 >
 > The patch below still fails when the height of the window is 1 line.
 >
 > Maybe Martin could help?
 >
 >> diff --git a/lisp/tab-bar.el b/lisp/tab-bar.el
 >> index 35474e1c674..08f904ec73d 100644
 >> --- a/lisp/tab-bar.el
 >> +++ b/lisp/tab-bar.el
 >> @@ -1586,7 +1595,8 @@ tab-bar-new-tab-to
 >>                 (window-state-put (window-state-get))
 >>               ;; Create a new window to get rid of old window parameters
 >>               ;; (e.g. prev/next buffers) of old window.
 >> -            (split-window) (delete-window))))
 >> +            (let ((window-min-height 1)) (split-window))
 >> +            (delete-window))))
 >>
 >>         (let ((buffer
 >>                (if (and (functionp tab-bar-new-tab-choice)
 >> diff --git a/lisp/window.el b/lisp/window.el
 >> index aa7520f30fa..b2ee869940a 100644
 >> --- a/lisp/window.el
 >> +++ b/lisp/window.el
 >> @@ -6391,7 +6396,8 @@ window-state-put
 >>                        (selected-window)))
 >>         (delete-other-windows-internal window root)
 >>         ;; Create a new window to replace the existing one.
 >> -      (setq window (prog1 (split-window window)
 >> +      (setq window (prog1 (let ((window-min-height 1))
 >> +                            (split-window window))
 >>                        (delete-window window)))))
 >>
 >>     (set-window-dedicated-p window nil)

Split the window horizontally.  If a user can see the "+" button on the
tab bar, the containing frame should be wide enough to accommodate two
side-by-side windows.  Also it's always better to specify an explicit
SIZE argument to make a small window than to bind 'window-min-height'.

For Emacs 30 I'd recommend a new routine say 'clean-window' to make its
argument window pristine.  The way you do it now loses all overlays with
a window property in the window's buffer.

martin

bug#62592: Not creating new Tabs with small window

[Juri Linkov]

>>>>> 3. resize the Emacs window to a small one, but large enough to show some Tab labels
>>>>> 4. 1x click on rightmost * in the Tab Bar to create a new Tab
>>>>>     split-window: Window #<window 3 on*Messages*> too small for splitting
>>> -      (setq window (prog1 (split-window window)
>>> +      (setq window (prog1 (let ((window-min-height 1))
>>> +                            (split-window window))
>
> Split the window horizontally.  If a user can see the "+" button on the
> tab bar, the containing frame should be wide enough to accommodate two
> side-by-side windows.  Also it's always better to specify an explicit
> SIZE argument to make a small window than to bind 'window-min-height'.

Thanks for the suggestion.  Empirically I found that
'(split-window-horizontally 1)' always fails.
So the next patch uses '(split-window-horizontally 2)'.

> For Emacs 30 I'd recommend a new routine say 'clean-window' to make its
> argument window pristine.  The way you do it now loses all overlays with
> a window property in the window's buffer.

The purpose of this trick is to change window identity.  So maybe
a better name would be 'clone-window'?

diff --git a/lisp/tab-bar.el b/lisp/tab-bar.el
index 9d703b5d048..43c24eb46ad 100644
--- a/lisp/tab-bar.el
+++ b/lisp/tab-bar.el
@@ -1585,7 +1585,7 @@ tab-bar-new-tab-to
               (window-state-put (window-state-get))
             ;; Create a new window to get rid of old window parameters
             ;; (e.g. prev/next buffers) of old window.
-            (split-window) (delete-window))))
+            (split-window-horizontally 2) (delete-window))))
 
       (let ((buffer
              (if (and (functionp tab-bar-new-tab-choice)
diff --git a/lisp/window.el b/lisp/window.el
index aa7520f30fa..1b497254a02 100644
--- a/lisp/window.el
+++ b/lisp/window.el
@@ -6391,7 +6391,7 @@ window-state-put
                      (selected-window)))
       (delete-other-windows-internal window root)
       ;; Create a new window to replace the existing one.
-      (setq window (prog1 (split-window window)
+      (setq window (prog1 (split-window-horizontally 2 window)
                      (delete-window window)))))
 
   (set-window-dedicated-p window nil)

bug#62592: Not creating new Tabs with small window

[martin rudalics]

 > Thanks for the suggestion.  Empirically I found that
 > '(split-window-horizontally 1)' always fails.
 > So the next patch uses '(split-window-horizontally 2)'.

1 is less than 'window-safe-min-width' (the doc-string of 'split-window'
says in this regard that "this function can make a new window as small
as one line or two columns").  And are you sure you want to copy the
'quit-restore' parameter?  As a rule, in Lisp code never use the
-vertically/-horizontally postfixed forms of 'split-window' unless you
want to mock their interactive behavior.

 >> For Emacs 30 I'd recommend a new routine say 'clean-window' to make its
 >> argument window pristine.  The way you do it now loses all overlays with
 >> a window property in the window's buffer.
 >
 > The purpose of this trick is to change window identity.  So maybe
 > a better name would be 'clone-window'?

Funny - here I use that for a window that can shadow an existing window
for redisplay purposes.  If you want the selected window to change
identity, you should say that in a comment.

martin

bug#62592: Not creating new Tabs with small window

[Juri Linkov]

>> Thanks for the suggestion.  Empirically I found that
>> '(split-window-horizontally 1)' always fails.
>> So the next patch uses '(split-window-horizontally 2)'.
>
> 1 is less than 'window-safe-min-width' (the doc-string of 'split-window'
> says in this regard that "this function can make a new window as small
> as one line or two columns").  And are you sure you want to copy the
> 'quit-restore' parameter?  As a rule, in Lisp code never use the
> -vertically/-horizontally postfixed forms of 'split-window' unless you
> want to mock their interactive behavior.

Then the following patch seems the right way to implement this.

>>> For Emacs 30 I'd recommend a new routine say 'clean-window' to make its
>>> argument window pristine.  The way you do it now loses all overlays with
>>> a window property in the window's buffer.
>>
>> The purpose of this trick is to change window identity.  So maybe
>> a better name would be 'clone-window'?
>
> Funny - here I use that for a window that can shadow an existing window
> for redisplay purposes.  If you want the selected window to change
> identity, you should say that in a comment.

Actually, there are 2 cases:

1. when 'tab-bar-new-tab-choice' is not equal to 'window'
   then need to remove all old window parameters and
   create a new window, this is what split-window/delete-window do;

2. when 'tab-bar-new-tab-choice' is 'window', then need to create
   a new identity that keeps all window parameters, this is done by:
   (window-state-put (window-state-get))
   And comments are trying to explain this.

diff --git a/lisp/tab-bar.el b/lisp/tab-bar.el
index 9d703b5d048..aae80b28047 100644
--- a/lisp/tab-bar.el
+++ b/lisp/tab-bar.el
@@ -1585,7 +1585,8 @@ tab-bar-new-tab-to
               (window-state-put (window-state-get))
             ;; Create a new window to get rid of old window parameters
             ;; (e.g. prev/next buffers) of old window.
-            (split-window) (delete-window))))
+            (split-window nil window-safe-min-width t)
+            (delete-window))))
 
       (let ((buffer
              (if (and (functionp tab-bar-new-tab-choice)
diff --git a/lisp/window.el b/lisp/window.el
index aa7520f30fa..ab7dd5ced12 100644
--- a/lisp/window.el
+++ b/lisp/window.el
@@ -6391,7 +6391,7 @@ window-state-put
                      (selected-window)))
       (delete-other-windows-internal window root)
       ;; Create a new window to replace the existing one.
-      (setq window (prog1 (split-window window)
+      (setq window (prog1 (split-window window window-safe-min-width t)
                      (delete-window window)))))
 
   (set-window-dedicated-p window nil)

bug#62592: Not creating new Tabs with small window

[martin rudalics]

 > Then the following patch seems the right way to implement this.

LGTM

martin

bug#62592: Not creating new Tabs with small window

[Juri Linkov]

close 62592 29.0.60
thanks

>> Then the following patch seems the right way to implement this.
>
> LGTM

So now pushed to emacs-29, and closed.