index.js 1.6 KB

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  1. 'use strict';
  2. Object.defineProperty(exports, "__esModule", {
  3. value: true
  4. });
  5. var _postcss = require('postcss');
  6. var _postcss2 = _interopRequireDefault(_postcss);
  7. function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
  8. var OVERRIDABLE_RULES = ['keyframes', 'counter-style'];
  9. var SCOPE_RULES = ['media', 'supports'];
  10. function isOverridable(name) {
  11. return OVERRIDABLE_RULES.indexOf(_postcss2.default.vendor.unprefixed(name)) !== -1;
  12. }
  13. function isScope(name) {
  14. return SCOPE_RULES.indexOf(_postcss2.default.vendor.unprefixed(name)) !== -1;
  15. }
  16. function getScope(node) {
  17. var current = node.parent;
  18. var chain = [node.name, node.params];
  19. do {
  20. if (current.type === 'atrule' && isScope(current.name)) {
  21. chain.unshift(current.name + ' ' + current.params);
  22. }
  23. current = current.parent;
  24. } while (current);
  25. return chain.join('|');
  26. }
  27. exports.default = _postcss2.default.plugin('postcss-discard-overridden', function () {
  28. return function (css) {
  29. var cache = {};
  30. var rules = [];
  31. css.walkAtRules(function (rule) {
  32. if (rule.type === 'atrule' && isOverridable(rule.name)) {
  33. var scope = getScope(rule);
  34. cache[scope] = rule;
  35. rules.push({
  36. node: rule,
  37. scope: scope
  38. });
  39. }
  40. });
  41. rules.forEach(function (rule) {
  42. if (cache[rule.scope] !== rule.node) {
  43. rule.node.remove();
  44. }
  45. });
  46. };
  47. });
  48. module.exports = exports['default'];