Issue 5094 - Implement support for :has() in chrome extension

include.preload.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2017 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
@@ skipping 111 matching lines @@
   {
     if (/^(?!https?:)[\w-]+:/i.test(urls[i]))
       urls.splice(i--, 1);
   }
 
   return urls;
 }
 
 function hideElement(element)
 {
-  function doHide(element)
+  function doHide(el)
   {
     let propertyName = "display";
     let propertyValue = "none";
-    if (element.localName == "frame")
+    if (el.localName == "frame")
     {
       propertyName = "visibility";
       propertyValue = "hidden";
     }
 
-    if (element.style.getPropertyValue(propertyName) != propertyValue ||
-        element.style.getPropertyPriority(propertyName) != "important")
-      element.style.setProperty(propertyName, propertyValue, "important");
+    if (el.style.getPropertyValue(propertyName) != propertyValue ||
+        el.style.getPropertyPriority(propertyName) != "important")
+      el.style.setProperty(propertyName, propertyValue, "important");
   }
 
   doHide(element);
 
   new MutationObserver(doHide).observe(
     element, {
       attributes: true,
       attributeFilter: ["style"]
     }
   );
@@ skipping 30 matching lines @@
 function checkSitekey()
 {
   let attr = document.documentElement.getAttribute("data-adblockkey");
   if (attr)
     ext.backgroundPage.sendMessage({type: "filters.addKey", token: attr});
 }
 
 function ElementHidingTracer()
 {
   this.selectors = [];
-  this.filters = [];
-
   this.changedNodes = [];
   this.timeout = null;
-
   this.observer = new MutationObserver(this.observe.bind(this));
   this.trace = this.trace.bind(this);
 
   if (document.readyState == "loading")
     document.addEventListener("DOMContentLoaded", this.trace);
   else
     this.trace();
 }
 ElementHidingTracer.prototype = {
   addSelectors(selectors, filters)
   {
+    let pairs = selectors.map((sel, i) => [sel, filters && filters[i]]);
+
     if (document.readyState != "loading")
-      this.checkNodes([document], selectors, filters);
-
-    this.selectors.push(...selectors);
-    this.filters.push(...filters);
-  },
-
-  reportFilters(filters)
-  {
-    let matchedSelectors = [];
-    for (let filter of filters)
-      matchedSelectors.push(filter.replace(/^.*?##/, ""));
-
-    ext.backgroundPage.sendMessage({
-      type: "devtools.traceElemHide",
-      selectors: matchedSelectors
-    });
-  },
-
-  checkNodes(nodes, selectors, filters)
-  {
-    let matchedSelectors = [];
-
-    for (let i = 0; i < selectors.length; i++)
+      this.checkNodes([document], pairs);
+
+    this.selectors.push(...pairs);
+  },
+
+  checkNodes(nodes, pairs)
+  {
+    let selectors = [];
+    let filters = [];
+
+    for (let [selector, filter] of pairs)
     {
       nodes: for (let node of nodes)
       {
-        let elements = node.querySelectorAll(selectors[i]);
-
-        for (let element of elements)
+        for (let element of node.querySelectorAll(selector))
         {
           // Only consider selectors that actually have an effect on the
           // computed styles, and aren't overridden by rules with higher
           // priority, or haven't been circumvented in a different way.
           if (getComputedStyle(element).display == "none")
           {
-            matchedSelectors.push(filters[i]);
+            // For regular element hiding, we don't know the exact filter,
+            // but the background page can find it with the given selector.
+            // In case of element hiding emulation, the generated selector
+            // we got here is different from the selector part of the filter,
+            // but in this case we can send the whole filter text instead.
+            if (filter)
+              filters.push(filter);
+            else
+              selectors.push(selector);
+
             break nodes;
           }
         }
       }
     }
 
-    if (matchedSelectors.length > 0)
-      this.reportFilters(matchedSelectors);
+    if (selectors.length > 0 || filters.length > 0)
+    {
+      ext.backgroundPage.sendMessage({
+        type: "devtools.traceElemHide",
+        selectors, filters
+      });
+    }
   },
 
   onTimeout()
   {
-    this.checkNodes(this.changedNodes, this.selectors, this.filters);
+    this.checkNodes(this.changedNodes, this.selectors);
     this.changedNodes = [];
     this.timeout = null;
   },
 
   observe(mutations)
   {
     // Forget previously changed nodes that are no longer in the DOM.
     for (let i = 0; i < this.changedNodes.length; i++)
     {
       if (!document.contains(this.changedNodes[i]))
@@ skipping 41 matching lines @@
 
     // Check only nodes whose descendants have changed, and not more often
     // than once a second. Otherwise large pages with a lot of DOM mutations
     // (like YouTube) freeze when the devtools panel is active.
     if (this.timeout == null)
       this.timeout = setTimeout(this.onTimeout.bind(this), 1000);
   },
 
   trace()
   {
-    this.checkNodes([document], this.selectors, this.filters);
+    this.checkNodes([document], this.selectors);
 
     this.observer.observe(
       document,
       {
         childList: true,
         attributes: true,
         subtree: true
       }
     );
   },
 
   disconnect()
   {
     document.removeEventListener("DOMContentLoaded", this.trace);
     this.observer.disconnect();
     clearTimeout(this.timeout);
   }
 };
 
-function runInPageContext(fn, arg)
-{
-  let script = document.createElement("script");
-  script.type = "application/javascript";
-  script.async = false;
-  script.textContent = "(" + fn + ")(" + JSON.stringify(arg) + ");";
-  document.documentElement.appendChild(script);
-  document.documentElement.removeChild(script);
-}
-
-// Before Chrome 58 the webRequest API didn't allow us to intercept
-// WebSockets[1], and therefore some ad networks are misusing them as a way to
-// serve adverts and circumvent us. As a workaround we wrap WebSocket,
-// preventing blocked WebSocket connections from being opened.
-// [1] - https://bugs.chromium.org/p/chromium/issues/detail?id=129353
-function wrapWebSocket()
-{
-  let randomEventName = "abpws-" + Math.random().toString(36).substr(2);
-
-  document.addEventListener(randomEventName, event =>
-  {
-    ext.backgroundPage.sendMessage({
-      type: "request.websocket",
-      url: event.detail.url
-    }, block =>
-    {
-      document.dispatchEvent(new CustomEvent(
-        randomEventName + "-" + event.detail.url, {detail: block}
-      ));
-    });
-  });
-
-  runInPageContext(eventName =>
-  {
-    // As far as possible we must track everything we use that could be
-    // sabotaged by the website later in order to circumvent us.
-    let RealWebSocket = WebSocket;
-    let RealCustomEvent = window.CustomEvent;
-    let closeWebSocket = Function.prototype.call.bind(
-      RealWebSocket.prototype.close
-    );
-    let addEventListener = document.addEventListener.bind(document);
-    let removeEventListener = document.removeEventListener.bind(document);
-    let dispatchEvent = document.dispatchEvent.bind(document);
-
-    function checkRequest(url, callback)
-    {
-      let incomingEventName = eventName + "-" + url;
-      function listener(event)
-      {
-        callback(event.detail);
-        removeEventListener(incomingEventName, listener);
-      }
-      addEventListener(incomingEventName, listener);
-
-      dispatchEvent(new RealCustomEvent(eventName, {detail: {url}}));
-    }
-
-    function WrappedWebSocket(url, ...args)
-    {
-      // Throw correct exceptions if the constructor is used improperly.
-      if (!(this instanceof WrappedWebSocket)) return RealWebSocket();
-      if (arguments.length < 1) return new RealWebSocket();
-
-      let websocket = new RealWebSocket(url, ...args);
-
-      checkRequest(websocket.url, blocked =>
-      {
-        if (blocked)
-          closeWebSocket(websocket);
-      });
-
-      return websocket;
-    }
-    WrappedWebSocket.prototype = RealWebSocket.prototype;
-    window.WebSocket = WrappedWebSocket.bind();
-    Object.defineProperties(WebSocket, {
-      CONNECTING: {value: RealWebSocket.CONNECTING, enumerable: true},
-      OPEN: {value: RealWebSocket.OPEN, enumerable: true},
-      CLOSING: {value: RealWebSocket.CLOSING, enumerable: true},
-      CLOSED: {value: RealWebSocket.CLOSED, enumerable: true},
-      prototype: {value: RealWebSocket.prototype}
-    });
-
-    RealWebSocket.prototype.constructor = WebSocket;
-  }, randomEventName);
-}
-
 function ElemHide()
 {
   this.shadow = this.createShadowTree();
   this.style = null;
   this.tracer = null;
 
   this.elemHideEmulation = new ElemHideEmulation(
     window,
     callback =>
     {
@@ skipping 23 matching lines @@
     if (/\.(?:google|blogger)\.com$/.test(document.domain))
       return null;
 
     // Finally since some users have both AdBlock and Adblock Plus installed we
     // have to consider how the two extensions interact. For example we want to
     // avoid creating the shadowRoot twice.
     let shadow = document.documentElement.shadowRoot ||
                  document.documentElement.createShadowRoot();
     shadow.appendChild(document.createElement("shadow"));
 
-    // Stop the website from messing with our shadow root (#4191, #4298).
-    if ("shadowRoot" in Element.prototype)
-    {
-      runInPageContext(() =>
-      {
-        let ourShadowRoot = document.documentElement.shadowRoot;
-        if (!ourShadowRoot)
-          return;
-        let desc = Object.getOwnPropertyDescriptor(Element.prototype,
-                                                   "shadowRoot");
-        let shadowRoot = Function.prototype.call.bind(desc.get);
-
-        Object.defineProperty(Element.prototype, "shadowRoot", {
-          configurable: true, enumerable: true, get()
-          {
-            let thisShadow = shadowRoot(this);
-            return thisShadow == ourShadowRoot ? null : thisShadow;
-          }
-        });
-      }, null);
-    }
-
     return shadow;
   },
 
   addSelectors(selectors, filters)
   {
     if (selectors.length == 0)
       return;
 
     if (!this.style)
     {
@@ skipping 39 matching lines @@
     for (let i = 0; i < preparedSelectors.length; i += this.selectorGroupSize)
     {
       let selector = preparedSelectors.slice(
         i, i + this.selectorGroupSize
       ).join(", ");
       this.style.sheet.insertRule(selector + "{display: none !important;}",
                                   this.style.sheet.cssRules.length);
     }
 
     if (this.tracer)
-      this.tracer.addSelectors(selectors, filters || selectors);
+      this.tracer.addSelectors(selectors, filters);
   },
 
   hideElements(elements, filters)
   {
     for (let element of elements)
       hideElement(element);
 
     if (this.tracer)
-      this.tracer.reportFilters(filters);
+    {
+      ext.backgroundPage.sendMessage({
+        type: "devtools.traceElemHide",
+        selectors: [],
+        filters
+      });
+    }
   },
 
   apply()
   {
     ext.backgroundPage.sendMessage({type: "get-selectors"}, response =>
     {
       if (this.tracer)
         this.tracer.disconnect();
       this.tracer = null;
 
       if (this.style && this.style.parentElement)
         this.style.parentElement.removeChild(this.style);
       this.style = null;
 
       if (response.trace)
         this.tracer = new ElementHidingTracer();
 
       this.addSelectors(response.selectors);
       this.elemHideEmulation.apply();
     });
   }
 };
 
 if (document instanceof HTMLDocument)
 {
   checkSitekey();
-  wrapWebSocket();
 
   elemhide = new ElemHide();
   elemhide.apply();
 
   document.addEventListener("error", event =>
   {
     checkCollapse(event.target);
   }, true);
 
   document.addEventListener("load", event =>
   {
     let element = event.target;
     if (/^i?frame$/.test(element.localName))
       checkCollapse(element);
   }, true);
 }