Issue 4864 - Start using ESLint for adblockpluschrome

lib/devtools.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 26 matching lines @@
 let panels = Object.create(null);
 
 function hasPanels()
 {
   return Object.keys(panels).length > 0;
 }
 
 function getActivePanel(page)
 {
   let panel = panels[page.id];
-  if(panel && !panel.reload && !panel.reloading)
+  if (panel && !panel.reload && !panel.reloading)
     return panel;
   return null;
 }
 
 function getFilterInfo(filter)
 {
   if (!filter)
     return null;
 
   let userDefined = false;
   let subscriptionTitle = null;
 
   for (let subscription of filter.subscriptions)
   {
     if (!subscription.disabled)
     {
       if (subscription instanceof SpecialSubscription)
         userDefined = true;
       else
         subscriptionTitle = subscription.title;
     }
   }
 
   return {
     text: filter.text,
     whitelisted: filter instanceof WhitelistFilter,
-    userDefined: userDefined,
+    userDefined,
     subscription: subscriptionTitle
   };
 }
 
 function hasRecord(panel, request, filter)
 {
-  return panel.records.some(record =>
-    record.request.url       == request.url       &&
-    record.request.docDomain == request.docDomain &&
+  for (let record of panel.records)
+  {
+    if (record.request.url != request.url ||
+        record.request.docDomain != request.docDomain)
+      continue;
 
-    // Ignore partial (e.g. ELEMHIDE) whitelisting if there is already
-    // a DOCUMENT exception which disables all means of blocking.
-    (record.request.type == "DOCUMENT" ? nonRequestTypes.indexOf(request.type) != -1
-                                       : record.request.type == request.type) &&
+    if (record.request.type == "DOCUMENT")
+    {
+      // Ignore partial (e.g. ELEMHIDE) whitelisting if there is already
+      // a DOCUMENT exception which disables all means of blocking.
+      if (!nonRequestTypes.includes(request.type))
+        continue;
+    }
+    else if (record.request.type != request.type)
+      continue;
 
     // Matched element hiding filters don't relate to a particular request,
     // so we also have to match the CSS selector in order to distinguish them.

[Sebastian Noack, 2017/03/31 07:59:37]

While thinking about a nicer way to do these checks, it took me quite a while to
wrap my head around this comment. I know, I wrote it initially. :D But I think
the intention is clearer when we change it like this:
 
  ... so we have to compare the selector in order to avoid duplicates.

[kzar, 2017/03/31 08:27:38]

Done.

-    (record.filter && record.filter.selector) == (filter && filter.selector)
-  );
+    if ((record.filter && record.filter.selector) ==
+        (filter && filter.selector))
+      return true;
+  }
+
+  return false;
 }
 
 function addRecord(panel, request, filter)
 {
   if (!hasRecord(panel, request, filter))
   {
     panel.port.postMessage({
       type: "add-record",
-      request: request,
+      request,
       filter: getFilterInfo(filter)
     });
 
-    panel.records.push({
-      request: request,
-      filter: filter
-    });
+    panel.records.push({request, filter});
   }
 }
 
 function matchRequest(request)
 {
   return defaultMatcher.matchesAny(
     request.url,
     RegExpFilter.typeMap[request.type],
     request.docDomain,
     request.thirdParty,
     request.sitekey,
     request.specificOnly
   );
 }
 
 /**
  * Logs a request to the devtools panel.
  *
  * @param {Page}     page          The page the request occured on
  * @param {string}   url           The URL of the request
  * @param {string}   type          The request type
  * @param {string}   docDomain     The IDN-decoded hostname of the document
- * @param {boolean}  thirdParty    Whether the origin of the request and document differs
+ * @param {boolean}  thirdParty    Whether the origin of the request and
+ *                                 document differs
  * @param {?string}  sitekey       The active sitekey if there is any
  * @param {?boolean} specificOnly  Whether generic filters should be ignored
- * @param {?BlockingFilter} filter The matched filter or null if there is no match
+ * @param {?BlockingFilter} filter The matched filter or null if there is no
+ *                                 match
  */
 exports.logRequest = function(page, url, type, docDomain,
                               thirdParty, sitekey,
                               specificOnly, filter)
 {
   let panel = getActivePanel(page);
   if (panel)
   {
-    let request = {
-      url: url,
-      type: type,
-      docDomain: docDomain,
-      thirdParty: thirdParty,
-      sitekey: sitekey,
-      specificOnly: specificOnly
-    };
-
+    let request = {url, type, docDomain, thirdParty, sitekey, specificOnly};
     addRecord(panel, request, filter);
   }
 };
 
 /**
  * Logs active element hiding filters to the devtools panel.
  *
  * @param {Page}     page       The page the elements were hidden on
  * @param {string[]} selectors  The CSS selectors of active elemhide filters
  * @param {string}   docDomain  The IDN-decoded hostname of the document
@@ skipping 11 matching lines @@
       for (let filter of subscription.filters)
       {
         if (!(filter instanceof ElemHideFilter) &&
             !(filter instanceof ElemHideEmulationFilter))
           continue;
         if (selectors.indexOf(filter.selector) == -1)
           continue;
         if (!filter.isActiveOnDomain(docDomain))
           continue;
 
-        addRecord(panel, {type: "ELEMHIDE", docDomain: docDomain}, filter);
+        addRecord(panel, {type: "ELEMHIDE", docDomain}, filter);
       }
     }
   }
-};
+}
 
 /**
  * Logs a whitelisting filter, that disables (some kind of)
  * blocking for a particular document, to the devtools panel.
  *
  * @param {Page}         page      The page the whitelisting is active on
  * @param {string}       url       The url of the whitelisted document
- * @param {number}       typeMask  The bit mask of whitelisting types checked for
- * @param {string}       docDomain The IDN-decoded hostname of the parent document
+ * @param {number}       typeMask  The bit mask of whitelisting types checked
+ *                                 for
+ * @param {string}       docDomain The IDN-decoded hostname of the parent
+ *                                 document
  * @param {WhitelistFilter} filter The matched whitelisting filter
  */
-exports.logWhitelistedDocument = function(page, url, typeMask, docDomain, filter)
+exports.logWhitelistedDocument = function(page, url, typeMask, docDomain,
+                                          filter)
 {
   let panel = getActivePanel(page);
   if (panel)
   {
     for (let type of nonRequestTypes)
     {
       if (typeMask & filter.contentType & RegExpFilter.typeMap[type])
-        addRecord(panel, {url: url, type: type, docDomain: docDomain}, filter);
+        addRecord(panel, {url, type, docDomain}, filter);
     }
   }
 };
 
 /**
  * Checks whether a page is inspected by the devtools panel.
  *
  * @param {Page} page
  * @return {boolean}
  */
@@ skipping 113 matching lines @@
 {
   updateFilters([filter], false);
 }
 
 function onSubscriptionAdded(subscription)
 {
   if (subscription instanceof SpecialSubscription)
     updateFilters(subscription.filters, true);
 }
 
-chrome.runtime.onConnect.addListener(port =>
+chrome.runtime.onConnect.addListener(newPort =>
 {
-  let match = port.name.match(/^devtools-(\d+)$/);
+  let match = newPort.name.match(/^devtools-(\d+)$/);
   if (!match)
     return;
 
   let inspectedTabId = parseInt(match[1], 10);
   let localOnBeforeRequest = onBeforeRequest.bind();
 
   chrome.webRequest.onBeforeRequest.addListener(
     localOnBeforeRequest,
     {
-      urls:  ["<all_urls>"],
+      urls: ["<all_urls>"],
       types: ["main_frame"],
       tabId: inspectedTabId
     }
   );
 
   if (!hasPanels())
   {
     ext.pages.onLoading.addListener(onLoading);
     FilterNotifier.on("filter.added", onFilterAdded);
     FilterNotifier.on("filter.removed", onFilterRemoved);
     FilterNotifier.on("subscription.added", onSubscriptionAdded);
   }
 
-  port.onDisconnect.addListener(() =>
+  newPort.onDisconnect.addListener(() =>
   {
     delete panels[inspectedTabId];
     chrome.webRequest.onBeforeRequest.removeListener(localOnBeforeRequest);
 
     if (!hasPanels())
     {
       ext.pages.onLoading.removeListener(onLoading);
       FilterNotifier.off("filter.added", onFilterAdded);
       FilterNotifier.off("filter.removed", onFilterRemoved);
       FilterNotifier.off("subscription.added", onSubscriptionAdded);
     }
   });
 
-  panels[inspectedTabId] = {port: port, records: []};
+  panels[inspectedTabId] = {port: newPort, records: []};
 });
 
 port.on("devtools.traceElemHide", (message, sender) =>
 {
   logHiddenElements(
     sender.page, message.selectors,
     extractHostFromFrame(sender.frame)
   );
 });