Bug 1761975 - [devtools] Hide ExtensionContent.jsm when debugging page with WebExt content scripts. r=bomsy

Differential Revision: https://phabricator.services.mozilla.com/D148837

devtools/client/debugger/test/mochitest/browser_dbg-features-source-tree.js

@@ -393,19 +393,14 @@ add_task(async function testSourceTreeWithWebExtensionContentScript() {
   let dbg = await initDebugger("doc-content-script-sources.html");
   // Let some time for unexpected source to appear
   await wait(1000);
-  // Bug 1761975 - While the content script doesn't show up,
-  // the internals of WebExtension codebase appear in the debugger...
-  await waitForSourcesInSourceTree(dbg, ["ExtensionContent.jsm"]);
+  await waitForSourcesInSourceTree(dbg, []);
   await dbg.toolbox.closeToolbox();
 
   info("With the chrome preference, the content script shows up");
   await pushPref("devtools.chrome.enabled", true);
   const toolbox = await openToolboxForTab(gBrowser.selectedTab, "jsdebugger");
   dbg = createDebuggerContext(toolbox);
-  await waitForSourcesInSourceTree(dbg, [
-    "content_script.js",
-    "ExtensionContent.jsm",
-  ]);
+  await waitForSourcesInSourceTree(dbg, ["content_script.js"]);
   await selectSource(dbg, "content_script.js");
   ok(
     findElementWithSelector(dbg, ".sources-list .focused"),
@@ -445,7 +440,6 @@ add_task(async function testSourceTreeNamesForWebExtensions() {
     "Test content script extension",
     "Test content script extension is labeled properly"
   );
-  is(getLabel(dbg, 3), "resource://gre", "resource://gre is labeled properly");
 
   await dbg.toolbox.closeToolbox();
   await extension.unload();

devtools/server/actors/thread.js

@@ -2056,6 +2056,31 @@ const ThreadActor = ActorClassWithSpec(threadSpec, {
     this._shouldEmitNewSource = false;
   },
 
+  /**
+   * Filtering function to filter out sources for which we don't want to notify/create
+   * source actors
+   *
+   * @param {Debugger.Source} source
+   *        The source to accept or ignore
+   * @param Boolean
+   *        True, if we want to create a source actor.
+   */
+  _acceptSource(source) {
+    // We have some spurious source created by ExtensionContent.jsm when debugging tabs.
+    // These sources are internal stuff injected by WebExt codebase to implement content
+    // scripts. We can't easily ignore them from Debugger API, so ignore them
+    // when debugging a tab (i.e. browser-element). As we still want to debug them
+    // from the browser toolbox.
+    if (
+      this._parent.sessionContext.type == "browser-element" &&
+      source.url.endsWith("ExtensionContent.jsm")
+    ) {
+      return false;
+    }
+
+    return true;
+  },
+
   /**
    * Add the provided source to the server cache.
    *
@@ -2063,6 +2088,10 @@ const ThreadActor = ActorClassWithSpec(threadSpec, {
    *        The source that will be stored.
    */
   _addSource(source) {
+    if (!this._acceptSource(source)) {
+      return;
+    }
+
     // Preloaded WebExtension content scripts may be cached internally by
     // ExtensionContent.jsm and ThreadActor would ignore them on a page reload
     // because it finds them in the _debuggerSourcesSeen WeakSet,

devtools/server/tests/xpcshell/testactors.js

@@ -23,6 +23,9 @@ const {
 } = require("devtools/shared/specs/targets/window-global");
 const { tabDescriptorSpec } = require("devtools/shared/specs/descriptors/tab");
 const Targets = require("devtools/server/actors/targets/index");
+const {
+  createContentProcessSessionContext,
+} = require("devtools/server/actors/watcher/session-context");
 
 var gTestGlobals = new Set();
 DevToolsServer.addTestGlobal = function(global) {
@@ -150,6 +153,8 @@ const TestTargetActor = protocol.ActorClassWithSpec(windowGlobalTargetSpec, {
   initialize: function(conn, global) {
     protocol.Actor.prototype.initialize.call(this, conn);
     this.conn = conn;
+
+    this.sessionContext = createContentProcessSessionContext();
     this._global = global;
     this._global.wrappedJSObject = global;
     this.threadActor = new ThreadActor(this, this._global);