Stylus compilation information exporter

gistfile1.js

var EventEmitter = require('events').EventEmitter;

/**
 * Only works with https://github.com/tonistiigi/stylus/tree/sourcemaps
 * Usage:
 * var StylusInfo = require('./stylusinfo').StylusInfo;
 * var logger = new StylusInfo();
 * var options = ...
 * options._info = logger;
 * stylus(str, options).render(function(err, css) {
 *   console.log(logger.export());
 * });
 */

function Selector(selectors, file, line) {
  this.selectors = selectors;
  this.file = file;
  this.line = line;
}

function Call(pos, call, file, line) {
  this.pos = pos;
  this.call = call;
  this.file = file;
  this.line = line;
}

function Extend(pos, selector, file, line) {
  this.pos = pos;
  this.selector = selector;
  this.file = file;
  this.line = line;
}

function Ident(pos, ident, file, line) {
  this.pos = pos;
  this.ident = ident;
  this.file = file;
  this.line = line;
}


function StylusInfo() {
  this.selectors = [];
  this.calls = [];
  this.extends = [];
  this.idents = [];
  this.files = [];

  var self = this;

  this.on('selector', function(selectors, file, line) {
    self.selectors.push(new Selector(selectors, self.getFile(file), line));
  });

  var calls = {};
  this.on('call', function(pos, call, file, line) {
    file = self.getFile(file);
    var key = pos + '::' + call;
    if (!calls[key]) {
      self.calls.push(new Call(pos, call, file, line));
      calls[key] = true;
    }
  });

  var _extends = {};
  this.on('extend', function(pos, selector, file, line) {
    file = self.getFile(file);
    var key = pos + '::' + selector;
    if (!_extends[key]) {
      self.extends.push(new Extend(pos, selector, file, line));
      _extends[key] = true;
    }
  });

  var _idents = {};
  this.on('ident', function(pos, ident, file, line) {
    file = self.getFile(file);
    var key = pos + '::' + ident;
    if (!_idents[key]) {
      self.idents.push(new Ident(pos, ident, file, line));
      _idents[key] = true;
    }
  });

}
StylusInfo.prototype = new EventEmitter;


StylusInfo.prototype.getFile = function (path) {
  var index = this.files.indexOf(path);
  if (index === -1) {
    index = this.files.length;
    this.files.push(path);
  }
  return index;
}

StylusInfo.prototype.export = function () {
  return {
    selectors: this.selectors,
    calls: this.calls,
    extends: this.extends,
    idents: this.idents,
    files: this.files,
  }
}

module.exports = function() {
  return new StylusInfo();
}
module.exports.StylusInfo = StylusInfo;