TypeError: Cannot read properties of undefined (reading '0')

[murkle]

Attached file issue41.svg gives this error:

TypeError: Cannot read properties of undefined (reading '0')
    at Object.getPropertyDescriptor [as property] (C:\Users\<username>\AppData\Roaming\npm\node_modules\svgo\node_modules\csso\node_modules\css-tree\cjs\utils\names.cjs:69:24)

with this command
svgo issue41.svg
and also when opened here https://jakearchibald.github.io/svgomg/

(File is from the canvg test suite https://github.com/canvg/canvg/blob/master/test/svgs/issue41.svg )

[SethFalco]

The issue is ultimately that the file is a valid SVG, but has invalid styles, from what I understand.

Here is an MRE of the issue:

<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 225, 425">
  <path style="fill- opacity:0.5" d="M0 50 l50 50 0 20z"/>
</svg>

The parser encounters a CSS property, but the file jumps straight to declaring another CSS property rather than assigning a value to it.

(This appears to be done pseudo-accidentally in the test suite by putting a line break in the middle of the property name.)

I'm not sure if this should be resolved in CSSTree, CSSO, or SVGO. 🤔
Probably in CSSO or SVGO as it's ultimately invalid styles afaik, but I'll look into this further later. Just jotting notes down for now.