Subject: 8.0.50; When :height/:width image attribute is specified, :scale factor is not applied

From: David Ponce <[email-masked]>
Date: Fri, 16 Apr 2021 08:16:20 +0200

Hello,

For the image :scale attribute the Elisp reference manual say that:

      If both ‘:scale’ and ‘:height’/‘:width’ are
      specified, the height/width will be adjusted by the specified
      scaling factor.

It seems, however, that this is not true, when the :height or :width
or both attributes of an image are specified, the :scale factor is not
applied.  For ex., evaluating the below code in the *scratch* buffer
should produce images with same size, but in the 2nd case the scale
factor is not applied:

(progn
   (insert-image
    (find-image
     '((:file "/usr/share/icons/oxygen/base/22x22/places/folder.png"
              :type png
              :scale 2
              ))))
   (insert-image
    (find-image
     '((:file "/usr/share/icons/oxygen/base/22x22/places/folder.png"
              :type png
              :scale 2
              :height 22
              :width 22
              ))))
   )

So, either the manual is wrong, or (better IMO) the code should be
fixed.

Thanks & Regards,
David Ponce

In GNU Emacs 28.0.50 (build 4, x86_64-pc-linux-gnu, GTK+ Version 3.24.28, cairo version 1.16.0)
  of 2021-04-15 built on kilauea
Repository revision: c2372096433e6a7ab173e5f1993f0c65b85f353e
Repository branch: master
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