1 files changed, 82 insertions, 0 deletions
diff --git a/devtools/server/actors/targets/target-actor-registry.sys.mjs b/devtools/server/actors/targets/target-actor-registry.sys.mjs
new file mode 100644
index 0000000000..4cb6d13868
--- /dev/null
+++ b/devtools/server/actors/targets/target-actor-registry.sys.mjs
@@ -0,0 +1,82 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Keep track of all WindowGlobal target actors.
+// This is especially used to track the actors using Message manager connector,
+// or the ones running in the parent process.
+// Top level actors, like tab's top level target or parent process target
+// are still using message manager in order to avoid being destroyed on navigation.
+// And because of this, these actors aren't using JS Window Actor.
+const windowGlobalTargetActors = new Set();
+let xpcShellTargetActor = null;
+
+export var TargetActorRegistry = {
+  registerTargetActor(targetActor) {
+    windowGlobalTargetActors.add(targetActor);
+  },
+
+  unregisterTargetActor(targetActor) {
+    windowGlobalTargetActors.delete(targetActor);
+  },
+
+  registerXpcShellTargetActor(targetActor) {
+    xpcShellTargetActor = targetActor;
+  },
+
+  unregisterXpcShellTargetActor(targetActor) {
+    xpcShellTargetActor = null;
+  },
+
+  get xpcShellTargetActor() {
+    return xpcShellTargetActor;
+  },
+
+  /**
+   * Return the target actors matching the passed browser element id.
+   * In some scenarios, the registry can have multiple target actors for a given
+   * browserId (e.g. the regular DevTools content toolbox + DevTools WebExtensions targets).
+   *
+   * @param {Object} sessionContext: The Session Context to help know what is debugged.
+   *                                 See devtools/server/actors/watcher/session-context.js
+   * @param {String} connectionPrefix: DevToolsServerConnection's prefix, in order to select only actor
+   *                                   related to the same connection. i.e. the same client.
+   * @returns {Array<TargetActor>}
+   */
+  getTargetActors(sessionContext, connectionPrefix) {
+    const actors = [];
+    for (const actor of windowGlobalTargetActors) {
+      const isMatchingPrefix = actor.actorID.startsWith(connectionPrefix);
+      const isMatchingContext =
+        sessionContext.type == "all" ||
+        (sessionContext.type == "browser-element" &&
+          (actor.browserId == sessionContext.browserId ||
+            actor.openerBrowserId == sessionContext.browserId)) ||
+        (sessionContext.type == "webextension" &&
+          actor.addonId == sessionContext.addonId);
+      if (isMatchingPrefix && isMatchingContext) {
+        actors.push(actor);
+      }
+    }
+    return actors;
+  },
+
+  /**
+   * Helper for tests to help track the number of targets created for a given tab.
+   * (Used by browser_ext_devtools_inspectedWindow.js)
+   *
+   * @param {Number} browserId: ID for the tab
+   *
+   * @returns {Number} Number of targets for this tab.
+   */
+
+  getTargetActorsCountForBrowserElement(browserId) {
+    let count = 0;
+    for (const actor of windowGlobalTargetActors) {
+      if (actor.browserId == browserId) {
+        count++;
+      }
+    }
+    return count;
+  },
+};