src/node_modules/clean-css/lib/optimizer/level-2/extract-properties.js

// This extractor is used in level 2 optimizations
// IMPORTANT: Mind Token class and this code is not related!
// Properties will be tokenized in one step, see #429

var Token = require('../../tokenizer/token');
var serializeRules = require('../../writer/one-time').rules;
var serializeValue = require('../../writer/one-time').value;

function extractProperties(token) {
  var properties = [];
  var inSpecificSelector;
  var property;
  var name;
  var value;
  var i, l;

  if (token[0] == Token.RULE) {
    inSpecificSelector = !/[.+>~]/.test(serializeRules(token[1]));

    for (i = 0, l = token[2].length; i < l; i++) {
      property = token[2][i];

      if (property[0] != Token.PROPERTY) { continue; }

      name = property[1][1];
      if (name.length === 0) { continue; }

      value = serializeValue(property, i);

      properties.push([
        name,
        value,
        findNameRoot(name),
        token[2][i],
        name + ':' + value,
        token[1],
        inSpecificSelector
      ]);
    }
  } else if (token[0] == Token.NESTED_BLOCK) {
    for (i = 0, l = token[2].length; i < l; i++) {
      properties = properties.concat(extractProperties(token[2][i]));
    }
  }

  return properties;
}

function findNameRoot(name) {
  if (name == 'list-style') { return name; }
  if (name.indexOf('-radius') > 0) { return 'border-radius'; }
  if (name == 'border-collapse' || name == 'border-spacing' || name == 'border-image') { return name; }
  if (name.indexOf('border-') === 0 && /^border-\w+-\w+$/.test(name)) { return name.match(/border-\w+/)[0]; }
  if (name.indexOf('border-') === 0 && /^border-\w+$/.test(name)) { return 'border'; }
  if (name.indexOf('text-') === 0) { return name; }
  if (name == '-chrome-') { return name; }

  return name.replace(/^-\w+-/, '').match(/([a-zA-Z]+)/)[0].toLowerCase();
}

module.exports = extractProperties;