Opal-Estate-Pro/node_modules/csso/lib/compressor/restructure/1-initialMergeRuleset.js
2019-09-13 11:27:52 +07:00

49 lines
1.7 KiB
JavaScript
Executable File

var utils = require('./utils.js');
var walkRules = require('../../utils/walk.js').rules;
function processRuleset(node, item, list) {
var selectors = node.selector.selectors;
var declarations = node.block.declarations;
list.prevUntil(item.prev, function(prev) {
// skip non-ruleset node if safe
if (prev.type !== 'Ruleset') {
return utils.unsafeToSkipNode.call(selectors, prev);
}
var prevSelectors = prev.selector.selectors;
var prevDeclarations = prev.block.declarations;
// try to join rulesets with equal pseudo signature
if (node.pseudoSignature === prev.pseudoSignature) {
// try to join by selectors
if (utils.isEqualLists(prevSelectors, selectors)) {
prevDeclarations.appendList(declarations);
list.remove(item);
return true;
}
// try to join by declarations
if (utils.isEqualDeclarations(declarations, prevDeclarations)) {
utils.addSelectors(prevSelectors, selectors);
list.remove(item);
return true;
}
}
// go to prev ruleset if has no selector similarities
return utils.hasSimilarSelectors(selectors, prevSelectors);
});
};
// NOTE: direction should be left to right, since rulesets merge to left
// ruleset. When direction right to left unmerged rulesets may prevent lookup
// TODO: remove initial merge
module.exports = function initialMergeRuleset(ast) {
walkRules(ast, function(node, item, list) {
if (node.type === 'Ruleset') {
processRuleset(node, item, list);
}
});
};