bug#30746: window-text-pixel-width includes width of following propertized space

bug#30746: window-text-pixel-width includes width of following propertized space

[Clément Pit-Claudel]

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Hi all,

I'm trying to measure strings in an Emacs buffer.  The current code is yielding surprising results:

(progn
  (save-excursion
    (insert #("s " 1 2 (display (space :width (50))))))
  (window-text-pixel-size nil (point) (1+ (point))))

On my machine a single 's' is 8 pixels wide, but this snippet returns 58.  

The following snippet, however, returns 8 as expected:

(progn
  (save-excursion
    (insert "s "))
  (window-text-pixel-size nil (point) (1+ (point))))

It seems that adding a display property on the space changes the return value of window-text-pixel-size; is that expected?

Thanks,
Clément.


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bug#30746: window-text-pixel-width includes width of following propertized space

[Eli Zaretskii]

> From: Clément Pit-Claudel <clement.pitclaudel@live.com>
> Date: Wed, 7 Mar 2018 17:13:32 -0500
> 
> (progn
>   (save-excursion
>     (insert #("s " 1 2 (display (space :width (50))))))
>   (window-text-pixel-size nil (point) (1+ (point))))
> 
> On my machine a single 's' is 8 pixels wide, but this snippet returns 58.  
> 
> The following snippet, however, returns 8 as expected:
> 
> (progn
>   (save-excursion
>     (insert "s "))
>   (window-text-pixel-size nil (point) (1+ (point))))
> 
> It seems that adding a display property on the space changes the return value of window-text-pixel-size; is that expected?

It's expected given the relatively naïve implementation, which didn't
expect such calamities.  Hopefully now fixed on the master branch.

bug#30746: window-text-pixel-width includes width of following propertized space

[Clément Pit-Claudel]

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On 2018-03-08 08:33, Eli Zaretskii wrote:
>> From: Clément Pit-Claudel <clement.pitclaudel@live.com>
>> Date: Wed, 7 Mar 2018 17:13:32 -0500
>>
>> (progn
>>   (save-excursion
>>     (insert #("s " 1 2 (display (space :width (50))))))
>>   (window-text-pixel-size nil (point) (1+ (point))))
>>
>> On my machine a single 's' is 8 pixels wide, but this snippet returns 58.  
>>
>> The following snippet, however, returns 8 as expected:
>>
>> (progn
>>   (save-excursion
>>     (insert "s "))
>>   (window-text-pixel-size nil (point) (1+ (point))))
>>
>> It seems that adding a display property on the space changes the return value of window-text-pixel-size; is that expected?
> 
> It's expected given the relatively naïve implementation, which didn't
> expect such calamities.  Hopefully now fixed on the master branch.

Thanks a lot; the width is indeed fixed.  However, the fix seems to have broken the height calculation: the first snippet above now returns (8 . 0), whereas the second one returns (8 . 16).

Cheers,
Clément.


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bug#30746: window-text-pixel-width includes width of following propertized space

[Eli Zaretskii]

> Cc: 30746@debbugs.gnu.org
> From: Clément Pit-Claudel <clement.pitclaudel@live.com>
> Date: Fri, 16 Mar 2018 10:09:40 -0400
> 
> Thanks a lot; the width is indeed fixed.  However, the fix seems to have broken the height calculation: the first snippet above now returns (8 . 0), whereas the second one returns (8 . 16).

Fixed.

bug#30746: window-text-pixel-width includes width of following propertized space

[Clément Pit-Claudel]

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On 2018-03-16 12:13, Eli Zaretskii wrote:
>> Cc: 30746@debbugs.gnu.org
>> From: Clément Pit-Claudel <clement.pitclaudel@live.com>
>> Date: Fri, 16 Mar 2018 10:09:40 -0400
>>
>> Thanks a lot; the width is indeed fixed.  However, the fix seems to have broken the height calculation: the first snippet above now returns (8 . 0), whereas the second one returns (8 . 16).
> 
> Fixed.

Works perfectly. Thanks a lot.


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bug#30746: window-text-pixel-width includes width of following propertized space

[Stefan Kangas]

fixed 30746 26.1
close 30746
quit

Clément Pit-Claudel <clement.pitclaudel@live.com> writes:

> On 2018-03-16 12:13, Eli Zaretskii wrote:
>>> Cc: 30746@debbugs.gnu.org
>>> From: Clément Pit-Claudel <clement.pitclaudel@live.com>
>>> Date: Fri, 16 Mar 2018 10:09:40 -0400
>>>
>>> Thanks a lot; the width is indeed fixed.  However, the fix seems to have broken the height calculation: the first snippet above now returns (8 . 0), whereas the second one returns (8 . 16).
>>
>> Fixed.
>
> Works perfectly. Thanks a lot.

This was fixed by:

commit c4db7662bb4740f069e494cfe632c76a0d21d6d7
Author: Eli Zaretskii <eliz@gnu.org>
Date:   Fri Mar 16 18:11:07 2018 +0200

    Another followup to fixing 'window-text-pixel-width'

    * src/xdisp.c (Fwindow_text_pixel_size): Adjust the return value
    when we stop one buffer position short of TO.  (Bug#30746)

And:

commit f1f12d8be3ddc5aa0a79658f5b339c78742321fa
Author: Eli Zaretskii <eliz@gnu.org>
Date:   Thu Mar 8 15:32:23 2018 +0200

    Fix 'window-text-pixel-size' when display properties are around

    * src/xdisp.c (Fwindow_text_pixel_size): Correct the result when
    there's a display property at the  TO position, and the call to
    move_it_to overshoots.  (Bug#30746)

I'm therefore closing this bug report.

Best regards,
Stefan Kangas