Support unquoted attributes

[vzaidman]

if you have svgs with unquoted attributes such as:
xmlns="http://www.w3.org/2000/svg" width=20px height=20px

The error: Error in parsing SVG: Unquoted attribute value is emitted.

I've created a loader to temporary fix this in webpack:
https://www.npmjs.com/package/xml-fix-loader

{
  test: /\.svg$/,
  use: [
    { loader: 'file-loader' },
    { loader: 'svgo-loader' },
    { loader: 'xml-fix-loader' }
  ]
}

[rally25rs]

This error actually comes from the SAX parser that is parsing the SVG.

https://github.com/isaacs/sax-js/blob/5aee2163d55cff24b817bbf550bac44841f9df45/lib/sax.js#L1367

[SethFalco]

Sax now provides a separate option so that we can allow unquoted attributes while in strict mode.

Reference:

• chore: migrate to upstream sax #2017
• feat: add explicit option for unquoted attribute values isaacs/sax-js#268

However, I'm wondering if this really makes sense in the context of SVGO. Would you be able to share how you obtained this SVG with unquoted attributes? 🤔

For example, if it was handwritten, or created with tooling that no longer produced the erroneous output, then I'd be reluctant to enable the option. However, if it was created by a notable software/project that still has this behavior, then by all means I'd be happy to toggle it.

Just not sure if this makes sense in the context of SVGs.

[SethFalco]

I'll close this for now due to the lack of a response, but anyone is welcome to chime in or open a new issue on the topic when they're available to elaborate.