bug#26978: 25.2; incomplete display of SVG image

[Lars Ingebrigtsen <larsi@gnus.org>]

ynyaaa@gmail.com writes:

> test-svg/appearance-png.png is for test-svg/sample-png.svg
> (a scaled emacs icon, expected image).

The file is:

<svg xmlns="http://www.w3.org/2000/svg" width="100" height="100"
     xmlns:xlink="http://www.w3.org/1999/xlink">
  <rect fill="blue" width="100" height="100"/>
  <image xlink:href="emacs.png" width="100" height="100"/>
</svg>

If we change that to an absolute path (and add the "file://" bit), it
does display correctly here on this Debian Buster machine:

<svg xmlns="http://www.w3.org/2000/svg" width="100" height="100"
     xmlns:xlink="http://www.w3.org/1999/xlink">
  <rect fill="blue" width="100" height="100"/>
  <image xlink:href="file:///tmp/test-svg/emacs.png" width="100" height="100"/>
</svg>

As Eli says, it's probably due to differences in SVG libraries and what
they allow.  But interestingly enough, using "display" on the original
file works, and "display" uses rsvg, too.  (Emacs uses rsvg, right?)

So I'm wondering whether there's something we can tell the rsvg library
to make it find these sub-images, or something.  I mean, we could also
pre-process the SVG files, but that's more than a bit hacky...

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