current-media() does not interpolate variables, selector() does

[cspotcode]

I'd like to fix this bug and am hoping a maintainer can point me in the right direction.

selector() uses utils.compileSelectors() to render a full selector string. It combines nested selectors and performs variable interpolation. However, current-media() doesn't. Based on the way the latter is used in +cache(), I'm guessing it is supposed to behave like the former?

What's the best way to fix this? Should I implement a utils.compileMedia()? ac40442 seems to be a big media-query refactoring, and a good starting point for my implementation. Also, should current-media() be fixed, or should I add a new BIF that uses utils.compileMedia(), leaving current-media() intact?

I greatly appreciate any advice you can offer.

$foo = 'screen'
@media $foo
    mq: current-media() // expecting '@media screen' but get '@media ($foo)`

[Panya]

Hi. compileSelectors method doesn't interpolate the selectors (they're interpolated in the evaluator, see https://github.com/stylus/stylus/blob/dev/lib/visitor/evaluator.js#L244 and https://github.com/stylus/stylus/blob/dev/lib/visitor/evaluator.js#L1403-L1439).
This method generates nested selectors and resolves relative references (&, /, ^[0] etc.).

To fix the problem with current-media you need to modify its source https://github.com/stylus/stylus/blob/dev/lib/functions/current-media.js. Basically you need to evaluate value of the media query by invoking this.visit method (this inside every BIF is the reference to current Evaluator instance). Something like:

module.exports = function currentMedia(){
  var self = this;
  return new nodes.String(lookForMedia(this.closestBlock.node) || '');

  function lookForMedia(node){
    if ('media' == node.nodeName) {
      node.val = self.visit(node.val); // magic happens here, the `val` property is the unresolved value of the media query (`$foo` ident in an expression in our case).
      return node.toString();
    } else if (node.block.parent.node) {
      return lookForMedia(node.block.parent.node);
    }
  }
};

[Panya]

Fixed in the rc-0.54 branch.