Issue 4878 - Start using ESLint for adblockpluscore

lib/matcher.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2016 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 "use strict";
 
 /**
  * @fileOverview Matcher class implementing matching addresses against
  *               a list of filters.
  */
 
-let {Filter, RegExpFilter, WhitelistFilter} = require("filterClasses");
+const {Filter, WhitelistFilter} = require("filterClasses");
 
 /**
  * Blacklist/whitelist filter matching
  * @constructor
  */
 function Matcher()
 {
   this.clear();
 }
 exports.Matcher = Matcher;
@@ skipping 64 matching lines @@
           this.filterByKeyword[keyword] = list[0];
       }
     }
 
     delete this.keywordByFilter[filter.text];
   },
 
   /**
    * Chooses a keyword to be associated with the filter
    * @param {Filter} filter
-   * @return {String} keyword
+   * @return {string} keyword or an empty string if no keyword could be found
    */
   findKeyword(filter)
   {
     let result = "";
     let {text} = filter;
     if (Filter.regexpRegExp.test(text))
       return result;
 
     // Remove options
     let match = Filter.optionsRegExp.exec(text);
@@ skipping 24 matching lines @@
         resultCount = count;
         resultLength = candidate.length;
       }
     }
     return result;
   },
 
   /**
    * Checks whether a particular filter is being matched against.
    * @param {RegExpFilter} filter
-   * @return {Boolean}
+   * @return {boolean}
    */
   hasFilter(filter)
   {
     return (filter.text in this.keywordByFilter);
   },
 
   /**
    * Returns the keyword used for a filter, null for unknown filters.
    * @param {RegExpFilter} filter
-   * @return {String}
+   * @return {string}
    */
   getKeywordForFilter(filter)
   {
     if (filter.text in this.keywordByFilter)
       return this.keywordByFilter[filter.text];
     return null;
   },
 
   /**
    * Checks whether the entries for a particular keyword match a URL
-   * @param {String} keyword
-   * @param {String} location
-   * @param {Number} typeMask
-   * @param {String} docDomain
-   * @param {Boolean} thirdParty
-   * @param {String} sitekey
-   * @param {Boolean} specificOnly
-   * @return {Filter|null}
+   * @param {string} keyword
+   * @param {string} location
+   * @param {number} typeMask
+   * @param {string} docDomain
+   * @param {boolean} thirdParty
+   * @param {string} sitekey
+   * @param {boolean} specificOnly
+   * @return {?Filter}
    */
   _checkEntryMatch(keyword, location, typeMask, docDomain, thirdParty, sitekey,
                    specificOnly)
   {
     let list = this.filterByKeyword[keyword];
     for (let i = 0; i < list.length; i++)
     {
       let filter = list[i];
 
       if (specificOnly && filter.isGeneric() &&
           !(filter instanceof WhitelistFilter))
         continue;
 
       if (filter.matches(location, typeMask, docDomain, thirdParty, sitekey))
         return filter;
     }
     return null;
   },
 
   /**
    * Tests whether the URL matches any of the known filters
-   * @param {String} location URL to be tested
-   * @param {number} typeMask bitmask of content / request types to match
-   * @param {String} docDomain domain name of the document that loads the URL
-   * @param {Boolean} thirdParty should be true if the URL is a third-party
-   *                             request
-   * @param {String} sitekey public key provided by the document
-   * @param {Boolean} specificOnly should be true if generic matches should be
-   *                               ignored
-   * @return {RegExpFilter|null} matching filter or null
+   * @param {string} location
+   *   URL to be tested
+   * @param {number} typeMask
+   *   bitmask of content / request types to match
+   * @param {string} docDomain
+   *   domain name of the document that loads the URL
+   * @param {boolean} thirdParty
+   *   should be true if the URL is a third-party request
+   * @param {string} sitekey
+   *   public key provided by the document
+   * @param {boolean} specificOnly
+   *   should be true if generic matches should be ignored
+   * @return {?RegExpFilter}
+   *   matching filter or null
    */
   matchesAny(location, typeMask, docDomain, thirdParty, sitekey, specificOnly)
   {
     let candidates = location.toLowerCase().match(/[a-z0-9%]{3,}/g);
     if (candidates === null)
       candidates = [];
     candidates.push("");
     for (let i = 0, l = candidates.length; i < l; i++)
     {
       let substr = candidates[i];
       if (substr in this.filterByKeyword)
       {
         let result = this._checkEntryMatch(substr, location, typeMask,
                                            docDomain, thirdParty, sitekey,
                                            specificOnly);
         if (result)
           return result;
       }
     }
 
     return null;
   }
 };
 
 /**
  * Combines a matcher for blocking and exception rules, automatically sorts
  * rules into two Matcher instances.
  * @constructor
+ * @augments Matcher
  */
 function CombinedMatcher()
 {
   this.blacklist = new Matcher();
   this.whitelist = new Matcher();
   this.resultCache = Object.create(null);
 }
 exports.CombinedMatcher = CombinedMatcher;
 
 /**
  * Maximal number of matching cache entries to be kept
- * @type {Number}
+ * @type {number}
  */
 CombinedMatcher.maxCacheEntries = 1000;
 
 CombinedMatcher.prototype =
 {
   /**
    * Matcher for blocking rules.
    * @type {Matcher}
    */
   blacklist: null,
 
   /**
    * Matcher for exception rules.
    * @type {Matcher}
    */
   whitelist: null,
 
   /**
    * Lookup table of previous matchesAny results
    * @type {Object}
    */
   resultCache: null,
 
   /**
    * Number of entries in resultCache
-   * @type {Number}
+   * @type {number}
    */
   cacheEntries: 0,
 
   /**
    * @see Matcher#clear
    */
   clear()
   {
     this.blacklist.clear();
     this.whitelist.clear();
@@ skipping 33 matching lines @@
     if (this.cacheEntries > 0)
     {
       this.resultCache = Object.create(null);
       this.cacheEntries = 0;
     }
   },
 
   /**
    * @see Matcher#findKeyword
    * @param {Filter} filter
-   * @return {String} keyword
+   * @return {string} keyword
    */
   findKeyword(filter)
   {
     if (filter instanceof WhitelistFilter)
       return this.whitelist.findKeyword(filter);
     return this.blacklist.findKeyword(filter);
   },
 
   /**
    * @see Matcher#hasFilter
    * @param {Filter} filter
-   * @return {Boolean}
+   * @return {boolean}
    */
   hasFilter(filter)
   {
     if (filter instanceof WhitelistFilter)
       return this.whitelist.hasFilter(filter);
     return this.blacklist.hasFilter(filter);
   },
 
   /**
    * @see Matcher#getKeywordForFilter
    * @param {Filter} filter
-   * @return {String} keyword
+   * @return {string} keyword
    */
   getKeywordForFilter(filter)
   {
     if (filter instanceof WhitelistFilter)
       return this.whitelist.getKeywordForFilter(filter);
     return this.blacklist.getKeywordForFilter(filter);
   },
 
   /**
    * Checks whether a particular filter is slow
    * @param {RegExpFilter} filter
-   * @return {Boolean}
+   * @return {boolean}
    */
   isSlowFilter(filter)
   {
     let matcher = (
       filter instanceof WhitelistFilter ? this.whitelist : this.blacklist
     );
     if (matcher.hasFilter(filter))
       return !matcher.getKeywordForFilter(filter);
     return !matcher.findKeyword(filter);
   },
 
   /**
    * Optimized filter matching testing both whitelist and blacklist matchers
    * simultaneously. For parameters see Matcher.matchesAny().
    * @see Matcher#matchesAny
-   * @param {String} location URL to be tested
-   * @param {number} typeMask bitmask of content / request types to match
-   * @param {String} docDomain domain name of the document that loads the URL
-   * @param {Boolean} thirdParty should be true if the URL is a third-party
-   *                             request
-   * @param {String} sitekey public key provided by the document
-   * @param {Boolean} specificOnly should be true if generic matches should be
-   *                               ignored
-   * @return {RegExpFilter|null} matching filter or null
+   * @inheritdoc
    */
   matchesAnyInternal(location, typeMask, docDomain, thirdParty, sitekey,
                      specificOnly)
   {
     let candidates = location.toLowerCase().match(/[a-z0-9%]{3,}/g);
     if (candidates === null)
       candidates = [];
     candidates.push("");
 
     let blacklistHit = null;
@@ skipping 14 matching lines @@
           substr, location, typeMask, docDomain, thirdParty, sitekey,
           specificOnly
         );
       }
     }
     return blacklistHit;
   },
 
   /**
    * @see Matcher#matchesAny
-   * @param {String} location URL to be tested
-   * @param {number} typeMask bitmask of content / request types to match
-   * @param {String} docDomain domain name of the document that loads the URL
-   * @param {Boolean} thirdParty should be true if the URL is a third-party
-   *                             request
-   * @param {String} sitekey public key provided by the document
-   * @param {Boolean} specificOnly should be true if generic matches should be
-   *                               ignored
-   * @return {RegExpFilter} matching filter or null
+   * @inheritdoc
    */
   matchesAny(location, typeMask, docDomain, thirdParty, sitekey, specificOnly)
   {
     let key = location + " " + typeMask + " " + docDomain + " " + thirdParty +
       " " + sitekey + " " + specificOnly;
     if (key in this.resultCache)
       return this.resultCache[key];
 
     let result = this.matchesAnyInternal(location, typeMask, docDomain,
                                          thirdParty, sitekey, specificOnly);
 
     if (this.cacheEntries >= CombinedMatcher.maxCacheEntries)
     {
       this.resultCache = Object.create(null);
       this.cacheEntries = 0;
     }
 
     this.resultCache[key] = result;
     this.cacheEntries++;
 
     return result;
   }
 };
 
 /**
  * Shared CombinedMatcher instance that should usually be used.
  * @type {CombinedMatcher}
  */
-let defaultMatcher = exports.defaultMatcher = new CombinedMatcher();
+exports.defaultMatcher = new CombinedMatcher();