add to #2984: fix regressions, as per feedback and code review

platform/chromium/vapi-background.js

@@ -60,6 +60,7 @@ vAPI.supportsUserStylesheets =
     chrome.extensionTypes instanceof Object &&
     chrome.extensionTypes.CSSOrigin instanceof Object &&
     'USER' in chrome.extensionTypes.CSSOrigin;
+vAPI.insertCSS = chrome.tabs.insertCSS;
 
 var noopFunc = function(){};
 

platform/webext/vapi-usercss.js

@@ -85,7 +85,11 @@ vAPI.DOMFilterer.prototype = {
         var userStylesheet = vAPI.userStylesheet,
             addedSelectors = [];
         for ( var entry of this.addedCSSRules ) {
-            if ( this.disabled === false && entry.lazy ) {
+            if (
+                this.disabled === false &&
+                entry.lazy &&
+                entry.injected === false
+            ) {
                 userStylesheet.add(
                     entry.selectors + '\n{' + entry.declarations + '}'
                 );
@@ -114,15 +118,21 @@ vAPI.DOMFilterer.prototype = {
                 ? selectors.join(',\n')
                 : selectors;
         if ( selectorsStr.length === 0 ) { return; }
+        if ( details === undefined ) { details = {}; }
         var entry = {
             selectors: selectorsStr,
             declarations,
-            lazy: details !== undefined && details.lazy === true,
+            lazy: details.lazy === true,
-            internal: details && details.internal === true
+            internal: details.internal === true,
+            injected: details.injected === true
         };
         this.addedCSSRules.add(entry);
         this.filterset.add(entry);
-        if ( this.disabled === false && entry.lazy !== true ) {
+        if (
+            this.disabled === false &&
+            entry.lazy !== true &&
+            entry.injected !== true
+        ) {
             vAPI.userStylesheet.add(selectorsStr + '\n{' + declarations + '}');
         }
         this.commit();

src/js/contentscript.js

@@ -455,6 +455,7 @@ vAPI.DOMFilterer = (function() {
             ]);
         }
         this.raw = o.raw;
+        this.cost = 0;
         this.selector = o.selector;
         this.tasks = [];
         var tasks = o.tasks;
@@ -575,16 +576,24 @@ vAPI.DOMFilterer = (function() {
 
             this.addedNodes = this.removedNodes = false;
 
-            var afterResultset = new Set();
+            var afterResultset = new Set(),
+                t0 = Date.now(), t1, pselector;
 
             for ( entry of this.selectors ) {
-                nodes = entry[1].exec();
+                pselector = entry[1];
+                if ( pselector.cost > 100 ) { continue; }
+                nodes = pselector.exec();
                 i = nodes.length;
                 while ( i-- ) {
                     node = nodes[i];
                     this.domFilterer.hideNode(node);
                     afterResultset.add(node);
                 }
+                t1 = Date.now();
+                pselector.cost += t1 - t0;
+                t0 = t1;
+                // TODO: Consider adding logging ability to report disabled
+                //       precedural filter in the logger.
             }
             if ( afterResultset.size !== currentResultset.size ) {
                 this.addedNodesHandlerMissCount = 0;
@@ -1265,6 +1274,8 @@ vAPI.domSurveyor = (function() {
             return;
         }
 
+        var injected = cfeDetails.rulesInjected === true;
+
         if ( response.noCosmeticFiltering ) {
             vAPI.domFilterer = null;
             vAPI.domSurveyor = null;
@@ -1276,30 +1287,29 @@ vAPI.domSurveyor = (function() {
             domFilterer.exceptions = cfeDetails.exceptionFilters;
             domFilterer.addCSSRule(
                 cfeDetails.declarativeFilters,
-                'display: none !important;'
+                'display:none!important;',
+                { injected: injected }
             );
             domFilterer.addCSSRule(
                 cfeDetails.highGenericHideSimple,
                 'display:none!important;',
-                { type: 'simple', lazy: true }
+                { type: 'simple', lazy: true, injected: injected }
             );
             domFilterer.addCSSRule(
                 cfeDetails.highGenericHideComplex,
                 'display:none!important;',
-                { type: 'complex', lazy: true }
+                { type: 'complex', lazy: true, injected: injected }
             );
             domFilterer.addProceduralSelectors(cfeDetails.proceduralFilters);
         }
 
-        if ( cfeDetails.netFilters.length !== 0 ) {
+        if ( cfeDetails.netFilters.length !== 0 && injected !== true ) {
             vAPI.userStylesheet.add(
                 cfeDetails.netFilters + '\n{display:none!important;}');
         }
 
         vAPI.userStylesheet.apply();
 
-        var parent = document.head || document.documentElement;
-        if ( parent ) {
         // Library of resources is located at:
         // https://github.com/gorhill/uBlock/blob/master/assets/ublock/resources.txt
         if ( cfeDetails.scripts ) {
@@ -1317,7 +1327,6 @@ vAPI.domSurveyor = (function() {
             vAPI.injectScriptlet(document, text);
             vAPI.injectedScripts = text;
         }
-        }
 
         // https://github.com/chrisaljoudi/uBlock/issues/587
         // If no filters were found, maybe the script was injected before

src/js/cosmetic-filtering.js

@@ -625,6 +625,8 @@ var FilterContainer = function() {
     this.netSelectorCacheCountMax = netSelectorCacheHighWaterMark;
     this.selectorCacheTimer = null;
 
+    this.supportsUserStylesheets = vAPI.supportsUserStylesheets;
+
     // generic exception filters
     this.genericDonthideSet = new Set();
 
@@ -1964,6 +1966,26 @@ FilterContainer.prototype.retrieveGenericSelectors = function(request) {
 
 /******************************************************************************/
 
+FilterContainer.prototype.injectHideRules = function(
+    tabId,
+    frameId,
+    selectors,
+    runAt
+) {
+    var details = {
+        code: '',
+        cssOrigin: 'user',
+        frameId: frameId,
+        runAt: runAt
+    };
+    for ( var selector of selectors ) {
+        details.code = selector + '\n{display:none!important;}';
+        vAPI.insertCSS(tabId, details);
+    }
+};
+
+/******************************************************************************/
+
 FilterContainer.prototype.retrieveDomainSelectors = function(
     request,
     sender,
@@ -1973,6 +1995,9 @@ FilterContainer.prototype.retrieveDomainSelectors = function(
 
     console.time('cosmeticFilteringEngine.retrieveDomainSelectors');
 
+    // TODO: consider using MRUCache to quickly lookup all the previously
+    //       looked-up data.
+
     var hostname = this.µburi.hostnameFromURI(request.locationURL),
         domain = this.µburi.domainFromHostname(hostname) || hostname,
         pos = domain.indexOf('.'),
@@ -1998,7 +2023,7 @@ FilterContainer.prototype.retrieveDomainSelectors = function(
         netFilters: '',
         proceduralFilters: [],
         scripts: undefined,
-        cssRulesInjected: false
+        rulesInjected: false
     };
 
     if ( options.noCosmeticFiltering !== true ) {
@@ -2027,6 +2052,22 @@ FilterContainer.prototype.retrieveDomainSelectors = function(
         if ( (bucket = this.specificFilters.get('!' + this.noDomainHash)) ) {
             bucket.retrieve(hostname, exceptionSet);
         }
+
+        // Specific exception procedural cosmetic filters.
+        if ( (bucket = this.proceduralFilters.get('!' + domainHash)) ) {
+            bucket.retrieve(hostname, exceptionSet);
+        }
+        // Specific entity-based exception procedural cosmetic filters.
+        if ( entityHash !== undefined ) {
+            if ( (bucket = this.proceduralFilters.get('!' + entityHash)) ) {
+                bucket.retrieve(entity, exceptionSet);
+            }
+        }
+        // Special bucket for those filters without a valid
+        // domain name as per PSL.
+        if ( (bucket = this.proceduralFilters.get('!' + this.noDomainHash)) ) {
+            bucket.retrieve(hostname, exceptionSet);
+        }
         if ( exceptionSet.size !== 0 ) {
             r.exceptionFilters = µb.arrayFrom(exceptionSet);
         }
@@ -2126,6 +2167,27 @@ FilterContainer.prototype.retrieveDomainSelectors = function(
         r.netFilters = netFilters.join(',\n');
     }
 
+    if (
+        this.supportsUserStylesheets &&
+        sender instanceof Object &&
+        sender.tab instanceof Object &&
+        typeof sender.frameId === 'number'
+    ) {
+        this.injectHideRules(
+            sender.tab.id,
+            sender.frameId,
+            [ r.declarativeFilters.join(',\n'), r.netFilters ],
+            'document_start'
+        );
+        this.injectHideRules(
+            sender.tab.id,
+            sender.frameId,
+            [ r.highGenericHideSimple, r.highGenericHideComplex ],
+            'document_end'
+        );
+        r.rulesInjected = true;
+    }
+
     console.timeEnd('cosmeticFilteringEngine.retrieveDomainSelectors');
 
     return r;

src/js/reverselookup-worker.js

@@ -98,34 +98,13 @@ var fromNetFilter = function(details) {
 var fromCosmeticFilter = function(details) {
     var match = /^#@?#/.exec(details.rawFilter),
         prefix = match[0],
-        needle = details.rawFilter.slice(prefix.length),
+        selector = details.rawFilter.slice(prefix.length);
-        selector = needle;
 
-    // With low generic simple cosmetic filters, the class or id prefix
+    // The longer the needle, the lower the number of false positives.
-    // character is not part of the compiled data. So we must be ready to
+    var needles = selector.match(/\w+/g).sort(function(a, b) {
-    // look-up version of the selector without the prefix character.
+        return b.length - a.length;
-    var idOrClassPrefix = needle.charAt(0),
+    });
-        cssPrefixMatcher;
+    var reNeedle = new RegExp(needles[0], 'g');
-    if ( idOrClassPrefix === '#' ) {
-        cssPrefixMatcher = '#?';
-        needle = needle.slice(1);
-    } else if ( idOrClassPrefix === '.' ) {
-        cssPrefixMatcher = '\\.?';
-        needle = needle.slice(1);
-    } else {
-        idOrClassPrefix = '';
-        cssPrefixMatcher = '';
-    }
-
-    // https://github.com/gorhill/uBlock/issues/3101
-    //   Use `m` flag for efficient regex execution.
-    var reFilter = new RegExp(
-            '^\\[\\d,[^\\n]*\\\\*"' +
-            cssPrefixMatcher +
-            reEscapeCosmetic(needle) +
-            '\\\\*"[^\\n]*\\]$',
-            'gm'
-        );
 
     var reHostname = new RegExp(
         '^' +
@@ -159,7 +138,7 @@ var fromCosmeticFilter = function(details) {
     }
         
     var response = Object.create(null),
-        assetKey, entry, content, found, fargs;
+        assetKey, entry, content, found, beg, end, fargs;
 
     for ( assetKey in listEntries ) {
         entry = listEntries[assetKey];
@@ -169,28 +148,61 @@ var fromCosmeticFilter = function(details) {
             filterClassSeparator.length
         );
         found = undefined;
-        while ( (match = reFilter.exec(content)) !== null ) {
+        while ( (match = reNeedle.exec(content)) !== null ) {
-            fargs = JSON.parse(match[0]);
+            beg = content.lastIndexOf('\n', match.index);
+            if ( beg === -1 ) { beg = 0; }
+            end = content.indexOf('\n', reNeedle.lastIndex);
+            if ( end === -1 ) { end = content.length; }
+            fargs = JSON.parse(content.slice(beg, end));
             switch ( fargs[0] ) {
             case 0: // id-based
-            case 2: // class-based
+                if (
+                    fargs[1] === selector.slice(1) &&
+                    selector.charAt(0) === '#'
+                ) {
                     found = prefix + selector;
+                }
+                break;
+            case 1: // id-based
+                if (
+                    fargs[2] === selector.slice(1) &&
+                    selector.charAt(0) === '#'
+                ) {
+                    found = prefix + selector;
+                }
+                break;
+            case 2: // class-based
+                if (
+                    fargs[1] === selector.slice(1) &&
+                    selector.charAt(0) === '.'
+                ) {
+                    found = prefix + selector;
+                }
+                break;
+            case 3:
+                if (
+                    fargs[2] === selector.slice(1) &&
+                    selector.charAt(0) === '.'
+                ) {
+                    found = prefix + selector;
+                }
                 break;
             case 4:
             case 5:
             case 7:
-                found = prefix + selector;
+                if ( fargs[1] === selector ) {
-                break;
-            case 1:
-            case 3:
-                if ( fargs[2] === selector ) {
                     found = prefix + selector;
                 }
                 break;
             case 6:
             case 8:
             case 9:
-                if ( fargs[3] !== selector ) { break; }
+                if (
+                    fargs[0] === 8 && fargs[3] !== selector ||
+                    fargs[0] === 9 && JSON.parse(fargs[3]).raw !== selector
+                ) {
+                    break;
+                }
                 if (
                     fargs[2] === '' ||
                     reHostname.test(fargs[2]) === true ||
@@ -219,15 +231,6 @@ var fromCosmeticFilter = function(details) {
     });
 };
 
-// https://github.com/gorhill/uBlock/issues/2666
-//   Raw filters in compiled filter lists may have been JSON-stringified one or
-//   multiple times.
-
-var reEscapeCosmetic = function(s) {
-    return s.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')
-            .replace(/"/g, '\\\\*"');
-};
-
 /******************************************************************************/
 
 onmessage = function(e) { // jshint ignore:line