devtools/client/fronts/page-style.js

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 "use strict";
   6
   7 const {
   8   FrontClassWithSpec,
   9   registerFront,
  10 } = require("resource://devtools/shared/protocol.js");
  11 const {
  12   pageStyleSpec,
  13 } = require("resource://devtools/shared/specs/page-style.js");
  14
  15 /**
  16  * PageStyleFront, the front object for the PageStyleActor
  17  */
  18 class PageStyleFront extends FrontClassWithSpec(pageStyleSpec) {
  19   _attributesCache = new Map();
  20
  21   constructor(conn, targetFront, parentFront) {
  22     super(conn, targetFront, parentFront);
  23     this.inspector = this.getParent();
  24
  25     this._clearAttributesCache = this._clearAttributesCache.bind(this);
  26     this.on("stylesheet-updated", this._clearAttributesCache);
  27     this.walker.on("new-mutations", this._clearAttributesCache);
  28   }
  29
  30   form(form) {
  31     this._form = form;
  32   }
  33
  34   get walker() {
  35     return this.inspector.walker;
  36   }
  37
  38   get supportsFontStretchLevel4() {
  39     return this._form.traits && this._form.traits.fontStretchLevel4;
  40   }
  41
  42   get supportsFontStyleLevel4() {
  43     return this._form.traits && this._form.traits.fontStyleLevel4;
  44   }
  45
  46   get supportsFontVariations() {
  47     return this._form.traits && this._form.traits.fontVariations;
  48   }
  49
  50   get supportsFontWeightLevel4() {
  51     return this._form.traits && this._form.traits.fontWeightLevel4;
  52   }
  53
  54   getMatchedSelectors(node, property, options) {
  55     return super.getMatchedSelectors(node, property, options).then(ret => {
  56       return ret.matched;
  57     });
  58   }
  59
  60   async getApplied(node, options = {}) {
  61     const ret = await super.getApplied(node, options);
  62     return ret.entries;
  63   }
  64
  65   addNewRule(node, pseudoClasses) {
  66     return super.addNewRule(node, pseudoClasses).then(ret => {
  67       return ret.entries[0];
  68     });
  69   }
  70
  71   /**
  72    * Get an array of existing attribute values in a node document, given an attribute type.
  73    *
  74    * @param {String} search: A string to filter attribute value on.
  75    * @param {String} attributeType: The type of attribute we want to retrieve the values.
  76    * @param {Element} node: The element we want to get possible attributes for. This will
  77    *        be used to get the document where the search is happening.
  78    * @returns {Array<String>} An array of strings
  79    */
  80   async getAttributesInOwnerDocument(search, attributeType, node) {
  81     if (!attributeType) {
  82       throw new Error("`type` should not be empty");
  83     }
  84
  85     if (!search) {
  86       return [];
  87     }
  88
  89     const lcFilter = search.toLowerCase();
  90
  91     // If the new filter includes the string that was used on our last trip to the server,
  92     // we can filter the cached results instead of calling the server again.
  93     if (
  94       this._attributesCache &&
  95       this._attributesCache.has(attributeType) &&
  96       search.startsWith(this._attributesCache.get(attributeType).search)
  97     ) {
  98       const cachedResults = this._attributesCache
  99         .get(attributeType)
 100         .results.filter(item => item.toLowerCase().startsWith(lcFilter));
 101       this.emitForTests(
 102         "getAttributesInOwnerDocument-cache-hit",
 103         cachedResults
 104       );
 105       return cachedResults;
 106     }
 107
 108     const results = await super.getAttributesInOwnerDocument(
 109       search,
 110       attributeType,
 111       node
 112     );
 113     this._attributesCache.set(attributeType, { search, results });
 114     return results;
 115   }
 116
 117   _clearAttributesCache() {
 118     this._attributesCache.clear();
 119   }
 120 }
 121
 122 exports.PageStyleFront = PageStyleFront;
 123 registerFront(PageStyleFront);