Bug 1646456 - Add xpcshell test to check pool destruction when connection closes r=nchevobbe

Differential Revision: https://phabricator.services.mozilla.com/D80059

devtools/server/tests/xpcshell/test_connection_closes_all_pools.js

@@ -0,0 +1,100 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const { Pool } = require("devtools/shared/protocol/Pool");
+const {
+  DevToolsServerConnection,
+} = require("devtools/server/devtools-server-connection");
+const {
+  LocalDebuggerTransport,
+} = require("devtools/shared/transport/local-transport");
+
+// Helper class to assert how many times a Pool was destroyed
+class FakeActor extends Pool {
+  constructor(...args) {
+    super(...args);
+    this.destroyedCount = 0;
+  }
+
+  destroy() {
+    this.destroyedCount++;
+    super.destroy();
+  }
+}
+
+add_task(async function() {
+  const transport = new LocalDebuggerTransport();
+  const conn = new DevToolsServerConnection("prefix", transport);
+
+  // Setup a flat pool hierarchy with multiple pools:
+  //
+  // - pool1
+  //   |
+  //   \- actor1
+  //
+  // - pool2
+  //   |
+  //   |- actor2a
+  //   |
+  //   \- actor2b
+  //
+  // From the point of view of the DevToolsServerConnection, the only pools
+  // registered in _extraPools should be pool1 and pool2. Even though actor1,
+  // actor2a and actor2b extend Pool, they don't manage other pools.
+  const actor1 = new FakeActor(conn);
+  const pool1 = new Pool(conn, "pool-1");
+  pool1.manage(actor1);
+
+  const actor2a = new FakeActor(conn);
+  const actor2b = new FakeActor(conn);
+  const pool2 = new Pool(conn, "pool-2");
+  pool2.manage(actor2a);
+  pool2.manage(actor2b);
+
+  ok(!!actor1.actorID, "actor1 has a valid actorID");
+  ok(!!actor2a.actorID, "actor2a has a valid actorID");
+  ok(!!actor2b.actorID, "actor2b has a valid actorID");
+
+  conn.close();
+
+  equal(actor1.destroyedCount, 1, "actor1 was successfully destroyed");
+  equal(actor2a.destroyedCount, 1, "actor2 was successfully destroyed");
+  equal(actor2b.destroyedCount, 1, "actor2 was successfully destroyed");
+});
+
+add_task(async function() {
+  const transport = new LocalDebuggerTransport();
+  const conn = new DevToolsServerConnection("prefix", transport);
+
+  // Setup a nested pool hierarchy:
+  //
+  // - pool
+  //   |
+  //   \- parentActor
+  //      |
+  //      \- childActor
+  //
+  // Since parentActor is also an ActorPool from the point of view of the
+  // DevToolsServerConnection, it will attempt to destroy it when looping on
+  // this._extraPools. But since `parentActor` is also a direct child of `pool`,
+  // it has already been destroyed by the Pool destroy() mechanism.
+  //
+  // Here we check that we don't call destroy() too many times on a single Pool.
+  // Even though Pool::destroy() is stable when called multiple times, we can't
+  // guarantee the same for classes inheriting Pool.
+  const childActor = new FakeActor(conn);
+  const parentActor = new FakeActor(conn);
+  const pool = new Pool(conn, "pool");
+  pool.manage(parentActor);
+  parentActor.manage(childActor);
+
+  ok(!!parentActor.actorID, "customActor has a valid actorID");
+  ok(!!childActor.actorID, "childActor has a valid actorID");
+
+  conn.close();
+
+  equal(parentActor.destroyedCount, 1, "parentActor was destroyed once");
+  equal(parentActor.destroyedCount, 1, "customActor was destroyed once");
+});

devtools/server/tests/xpcshell/xpcshell.ini

@@ -239,3 +239,4 @@ skip-if = true # breakpoint sliding is not supported bug 1525685
 [test_symbolactor.js]
 [test_webext_apis.js]
 [test_restartFrame-01.js]
+[test_connection_closes_all_pools.js]