import { keyword as resolveKeyword } from 'css-tree'; import { hasNoChildren } from './utils.js'; export default function cleanAtrule(node, item, list) { if (node.block) { // otherwise removed at-rule don't prevent @import for removal if (this.stylesheet !== null) { this.stylesheet.firstAtrulesAllowed = false; } if (hasNoChildren(node.block)) { list.remove(item); return; } } switch (node.name) { case 'charset': if (hasNoChildren(node.prelude)) { list.remove(item); return; } // if there is any rule before @charset -> remove it if (item.prev) { list.remove(item); return; } break; case 'import': if (this.stylesheet === null || !this.stylesheet.firstAtrulesAllowed) { list.remove(item); return; } // if there are some rules that not an @import or @charset before @import // remove it list.prevUntil(item.prev, function(rule) { if (rule.type === 'Atrule') { if (rule.name === 'import' || rule.name === 'charset') { return; } } this.root.firstAtrulesAllowed = false; list.remove(item); return true; }, this); break; default: { const name = resolveKeyword(node.name).basename; if (name === 'keyframes' || name === 'media' || name === 'supports') { // drop at-rule with no prelude if (hasNoChildren(node.prelude) || hasNoChildren(node.block)) { list.remove(item); } } } } };