/node_modules/less-middleware/node_modules/less/lib/less/to-css-visitor.js
JavaScript | 243 lines | 204 code | 28 blank | 11 comment | 52 complexity | a1818cbaa7950b08c82ec85186b7af24 MD5 | raw file
Possible License(s): Apache-2.0, MIT, BSD-3-Clause, MPL-2.0-no-copyleft-exception, 0BSD
- (function (tree) {
- tree.toCSSVisitor = function(env) {
- this._visitor = new tree.visitor(this);
- this._env = env;
- };
- tree.toCSSVisitor.prototype = {
- isReplacing: true,
- run: function (root) {
- return this._visitor.visit(root);
- },
- visitRule: function (ruleNode, visitArgs) {
- if (ruleNode.variable) {
- return [];
- }
- return ruleNode;
- },
- visitMixinDefinition: function (mixinNode, visitArgs) {
- // mixin definitions do not get eval'd - this means they keep state
- // so we have to clear that state here so it isn't used if toCSS is called twice
- mixinNode.frames = [];
- return [];
- },
- visitExtend: function (extendNode, visitArgs) {
- return [];
- },
- visitComment: function (commentNode, visitArgs) {
- if (commentNode.isSilent(this._env)) {
- return [];
- }
- return commentNode;
- },
- visitMedia: function(mediaNode, visitArgs) {
- mediaNode.accept(this._visitor);
- visitArgs.visitDeeper = false;
- if (!mediaNode.rules.length) {
- return [];
- }
- return mediaNode;
- },
- visitDirective: function(directiveNode, visitArgs) {
- if (directiveNode.currentFileInfo.reference && !directiveNode.isReferenced) {
- return [];
- }
- if (directiveNode.name === "@charset") {
- // Only output the debug info together with subsequent @charset definitions
- // a comment (or @media statement) before the actual @charset directive would
- // be considered illegal css as it has to be on the first line
- if (this.charset) {
- if (directiveNode.debugInfo) {
- var comment = new tree.Comment("/* " + directiveNode.toCSS(this._env).replace(/\n/g, "")+" */\n");
- comment.debugInfo = directiveNode.debugInfo;
- return this._visitor.visit(comment);
- }
- return [];
- }
- this.charset = true;
- }
- if (directiveNode.rules && directiveNode.rules.rules) {
- this._mergeRules(directiveNode.rules.rules);
- }
- return directiveNode;
- },
- checkPropertiesInRoot: function(rules) {
- var ruleNode;
- for(var i = 0; i < rules.length; i++) {
- ruleNode = rules[i];
- if (ruleNode instanceof tree.Rule && !ruleNode.variable) {
- throw { message: "properties must be inside selector blocks, they cannot be in the root.",
- index: ruleNode.index, filename: ruleNode.currentFileInfo ? ruleNode.currentFileInfo.filename : null};
- }
- }
- },
- visitRuleset: function (rulesetNode, visitArgs) {
- var rule, rulesets = [];
- if (rulesetNode.firstRoot) {
- this.checkPropertiesInRoot(rulesetNode.rules);
- }
- if (! rulesetNode.root) {
- if (rulesetNode.paths) {
- rulesetNode.paths = rulesetNode.paths
- .filter(function(p) {
- var i;
- if (p[0].elements[0].combinator.value === ' ') {
- p[0].elements[0].combinator = new(tree.Combinator)('');
- }
- for(i = 0; i < p.length; i++) {
- if (p[i].getIsReferenced() && p[i].getIsOutput()) {
- return true;
- }
- }
- return false;
- });
- }
- // Compile rules and rulesets
- var nodeRules = rulesetNode.rules, nodeRuleCnt = nodeRules ? nodeRules.length : 0;
- for (var i = 0; i < nodeRuleCnt; ) {
- rule = nodeRules[i];
- if (rule && rule.rules) {
- // visit because we are moving them out from being a child
- rulesets.push(this._visitor.visit(rule));
- nodeRules.splice(i, 1);
- nodeRuleCnt--;
- continue;
- }
- i++;
- }
- // accept the visitor to remove rules and refactor itself
- // then we can decide now whether we want it or not
- if (nodeRuleCnt > 0) {
- rulesetNode.accept(this._visitor);
- } else {
- rulesetNode.rules = null;
- }
- visitArgs.visitDeeper = false;
- nodeRules = rulesetNode.rules;
- if (nodeRules) {
- this._mergeRules(nodeRules);
- nodeRules = rulesetNode.rules;
- }
- if (nodeRules) {
- this._removeDuplicateRules(nodeRules);
- nodeRules = rulesetNode.rules;
- }
- // now decide whether we keep the ruleset
- if (nodeRules && nodeRules.length > 0 && rulesetNode.paths.length > 0) {
- rulesets.splice(0, 0, rulesetNode);
- }
- } else {
- rulesetNode.accept(this._visitor);
- visitArgs.visitDeeper = false;
- if (rulesetNode.firstRoot || (rulesetNode.rules && rulesetNode.rules.length > 0)) {
- rulesets.splice(0, 0, rulesetNode);
- }
- }
- if (rulesets.length === 1) {
- return rulesets[0];
- }
- return rulesets;
- },
- _removeDuplicateRules: function(rules) {
- if (!rules) { return; }
- // remove duplicates
- var ruleCache = {},
- ruleList, rule, i;
- for(i = rules.length - 1; i >= 0 ; i--) {
- rule = rules[i];
- if (rule instanceof tree.Rule) {
- if (!ruleCache[rule.name]) {
- ruleCache[rule.name] = rule;
- } else {
- ruleList = ruleCache[rule.name];
- if (ruleList instanceof tree.Rule) {
- ruleList = ruleCache[rule.name] = [ruleCache[rule.name].toCSS(this._env)];
- }
- var ruleCSS = rule.toCSS(this._env);
- if (ruleList.indexOf(ruleCSS) !== -1) {
- rules.splice(i, 1);
- } else {
- ruleList.push(ruleCSS);
- }
- }
- }
- }
- },
- _mergeRules: function (rules) {
- if (!rules) { return; }
- var groups = {},
- parts,
- rule,
- key;
- for (var i = 0; i < rules.length; i++) {
- rule = rules[i];
- if ((rule instanceof tree.Rule) && rule.merge) {
- key = [rule.name,
- rule.important ? "!" : ""].join(",");
- if (!groups[key]) {
- groups[key] = [];
- } else {
- rules.splice(i--, 1);
- }
- groups[key].push(rule);
- }
- }
- Object.keys(groups).map(function (k) {
- function toExpression(values) {
- return new (tree.Expression)(values.map(function (p) {
- return p.value;
- }));
- }
- function toValue(values) {
- return new (tree.Value)(values.map(function (p) {
- return p;
- }));
- }
- parts = groups[k];
- if (parts.length > 1) {
- rule = parts[0];
- var spacedGroups = [];
- var lastSpacedGroup = [];
- parts.map(function (p) {
- if (p.merge==="+") {
- if (lastSpacedGroup.length > 0) {
- spacedGroups.push(toExpression(lastSpacedGroup));
- }
- lastSpacedGroup = [];
- }
- lastSpacedGroup.push(p);
- });
- spacedGroups.push(toExpression(lastSpacedGroup));
- rule.value = toValue(spacedGroups);
- }
- });
- }
- };
- })(require('./tree'));