Add replaceUse plugin

[tshedor]

This plugin replaces all <use> elements with the nodes they clone and removes the top-level xlink attribute. While this doesn't "optimize" the SVG, it allows the contents to be used in SVG sprites within <symbol> elements. This plugin is best used in conjunction with removeUselessDefs.

[bbqaaq]

This is a good plugins! I probably will use it in my project!

But Im suggesting to make this plugin being executed before the removeUselessDefs plugins, otherwise it will just duplicate the path after removing the <use> tag

[tshedor]

@bbqaaq Great call. I almost always run with multipass enabled, so I didn't notice. I've moved it before removeUselessDefs.

[TiagoDinisFonseca]

Hi, I was testing this plugin and I found several bugs:

• It is removing necessary IDs (remove line 22)
• The tag use can have some attributes, unfortunately we cannot copy it inside the object being moved, perhaps it is best to use a new group and some transformations
• It ignores all defined object outside defs (yes, it is possible to do so with a svg)

[tshedor]

@TiagoDinisFonseca I've addressed those bugs. Thanks for reporting them.

Regarding the <use> attributes, I changed the <use> tag into a group as per your suggestion, and my tests show equivalent behavior between <use> and <g>. However, please verify that your tests work as expected.

These fixes mean the plugin is no longer complimented by removeUselessDefs as it achieves the desired effect on its own.

[TiagoDinisFonseca]

Unfortunately, this is not true. The tag has some attributes: x, y, height and width that g has not.
(see https://developer.mozilla.org/en-US/docs/Web/SVG/Element/use)
x and y should be equivalent to a translate
height and width are still mysterious for me here
in all my experiences height and width do nothing

[bbqaaq]

As a user I do support adding this plugin as a optional one as I am useful with this.
In my project I got some SVGs with <use> and <defs> which is annoying to me

I have gone through this plugin and it works quite fine with the SVGs.

[lifeiscontent]

@TiagoDinisFonseca @tshedor any updates here? I'd really like to use this plugin.

[lifeiscontent]

I'd guess you should move the attributes from use to the path and not the tag.

[lifeiscontent]

@GreLI can we prioritize this?

what would you need in order to get this merged?

[TiagoDinisFonseca]

@lifeiscontent
At the time I was interested on this because it could be useful for me. It turns out, I was wrong.
Therefore, I did not care to solve its problems. Sorry for that, eventually I can do it when I have the time to run this on my personal PC.

But you can solve it:
1- Your solution is not good enough, you never know what is inside, it could be a second group.
2- I guess that attributes x and y can be transformed into some translation (x,y) => transform="translation(x, y)"
3- What about width and height??? I feel bad about erasing some fields just because I do not understand them.
3.1 - There is a solution for this: we erase those fields... if this is a problem, this will be a bug in the future (I don't like this attitude, but perhaps it is ok)

[tommoor]

Does this need to be absolutely perfect to be considered for addition? This would be very useful for me in it's current state

[akre54]

Rewritten to use the latest csstree api:

exports.fn = () => {
  const defs = new Map;
  const used = new Set;

  return {
    element: {
      enter(node, parentNode) {
        if (node.name === 'svg') {
          delete node.attributes['xmlns:xlink'];
          return
        }

        if (parentNode.name === 'defs') {
          defs.set('#' + node.attributes.id, node);
          return;
        }

        if (node.name === 'use') {
          const id = node.attributes.href || node.attributes['xlink:href'];
          const def = defs.get(id);

          if (!def) {
            console.warn(`Could not find definition for ${id}`);
            return;
          }

          delete node.attributes['xlink:href'];
          delete node.attributes['href'];

          node.name = 'g';
          node.children = [...def.children];

          used.add(def);
        }

      },
    },
    root: {
      exit(root) {
        const defs = querySelector(root, 'defs');
        if (defs) {
          defs.children = defs.children.filter(node => !used.has(node));
          if (!defs.children.length) {
            defs.parentNode.children = defs.parentNode.children.filter(node => node !== defs);
          }
        }
      }
    }
  }
}