refactor: sync emulation state with secondary clients (#10849)

packages/puppeteer-core/src/common/EmulationManager.ts

@@ -17,10 +17,24 @@ import {Protocol} from 'devtools-protocol';
 
 import {GeolocationOptions, MediaFeature} from '../api/Page.js';
 import {assert} from '../util/assert.js';
+import {invokeAtMostOnceForArguments} from '../util/decorators.js';
 import {isErrorLike} from '../util/ErrorLike.js';
 
 import {CDPSession, CDPSessionEmittedEvents} from './Connection.js';
 import {Viewport} from './PuppeteerViewport.js';
+import {debugError} from './util.js';
+
+interface ViewportState {
+  viewport?: Viewport;
+}
+
+interface IdleOverridesState {
+  overrides?: {
+    isUserActive: boolean;
+    isScreenUnlocked: boolean;
+  };
+  active: boolean;
+}
 
 /**
  * @internal
@@ -31,7 +45,10 @@ export class EmulationManager {
   #hasTouch = false;
   #javascriptEnabled = true;
 
-  #viewport?: Viewport;
+  #viewportState: ViewportState = {};
+  #idleOverridesState: IdleOverridesState = {
+    active: false,
+  };
   #secondaryClients = new Set<CDPSession>();
 
   constructor(client: CDPSession) {
@@ -45,10 +62,11 @@ export class EmulationManager {
 
   async registerSpeculativeSession(client: CDPSession): Promise<void> {
     this.#secondaryClients.add(client);
-    await this.#applyViewport(client);
     client.once(CDPSessionEmittedEvents.Disconnected, () => {
       return this.#secondaryClients.delete(client);
     });
+    void this.#syncViewport().catch(debugError);
+    void this.#syncIdleState().catch(debugError);
   }
 
   get javascriptEnabled(): boolean {
@@ -56,9 +74,11 @@ export class EmulationManager {
   }
 
   async emulateViewport(viewport: Viewport): Promise<boolean> {
-    this.#viewport = viewport;
+    this.#viewportState = {
+      viewport,
+    };
 
-    await this.#applyViewport(this.#client);
+    await this.#syncViewport();
 
     const mobile = viewport.isMobile || false;
     const hasTouch = viewport.hasTouch || false;
@@ -67,22 +87,27 @@ export class EmulationManager {
     this.#emulatingMobile = mobile;
     this.#hasTouch = hasTouch;
 
-    if (!reloadNeeded) {
-      // If the page will be reloaded, no need to adjust secondary clients.
-      await Promise.all(
-        Array.from(this.#secondaryClients).map(client => {
-          return this.#applyViewport(client);
-        })
-      );
-    }
     return reloadNeeded;
   }
 
-  async #applyViewport(client: CDPSession): Promise<void> {
-    const viewport = this.#viewport;
-    if (!viewport) {
+  async #syncViewport() {
+    await Promise.all([
+      this.#applyViewport(this.#client, this.#viewportState),
+      ...Array.from(this.#secondaryClients).map(client => {
+        return this.#applyViewport(client, this.#viewportState);
+      }),
+    ]);
+  }
+
+  @invokeAtMostOnceForArguments
+  async #applyViewport(
+    client: CDPSession,
+    viewportState: ViewportState
+  ): Promise<void> {
+    if (!viewportState.viewport) {
       return;
     }
+    const {viewport} = viewportState;
     const mobile = viewport.isMobile || false;
     const width = viewport.width;
     const height = viewport.height;
@@ -111,13 +136,37 @@ export class EmulationManager {
     isUserActive: boolean;
     isScreenUnlocked: boolean;
   }): Promise<void> {
-    if (overrides) {
-      await this.#client.send('Emulation.setIdleOverride', {
-        isUserActive: overrides.isUserActive,
-        isScreenUnlocked: overrides.isScreenUnlocked,
+    this.#idleOverridesState = {
+      active: true,
+      overrides,
+    };
+    await this.#syncIdleState();
+  }
+
+  async #syncIdleState() {
+    await Promise.all([
+      this.#emulateIdleState(this.#client, this.#idleOverridesState),
+      ...Array.from(this.#secondaryClients).map(client => {
+        return this.#emulateIdleState(client, this.#idleOverridesState);
+      }),
+    ]);
+  }
+
+  @invokeAtMostOnceForArguments
+  async #emulateIdleState(
+    client: CDPSession,
+    idleStateState: IdleOverridesState
+  ): Promise<void> {
+    if (!idleStateState.active) {
+      return;
+    }
+    if (idleStateState.overrides) {
+      await client.send('Emulation.setIdleOverride', {
+        isUserActive: idleStateState.overrides.isUserActive,
+        isScreenUnlocked: idleStateState.overrides.isScreenUnlocked,
       });
     } else {
-      await this.#client.send('Emulation.clearIdleOverride');
+      await client.send('Emulation.clearIdleOverride');
     }
   }
 

packages/puppeteer-core/src/util/decorators.test.ts

@@ -0,0 +1,89 @@
+/**
+ * Copyright 2023 Google Inc. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import {describe, it} from 'node:test';
+
+import expect from 'expect';
+import sinon from 'sinon';
+
+import {invokeAtMostOnceForArguments} from './decorators.js';
+
+describe('decorators', function () {
+  describe('invokeAtMostOnceForArguments', () => {
+    it('should delegate calls', () => {
+      const spy = sinon.spy();
+      class Test {
+        @invokeAtMostOnceForArguments
+        test(obj1: object, obj2: object) {
+          spy(obj1, obj2);
+        }
+      }
+      const t = new Test();
+      expect(spy.callCount).toBe(0);
+      const obj1 = {};
+      const obj2 = {};
+      t.test(obj1, obj2);
+      expect(spy.callCount).toBe(1);
+    });
+
+    it('should prevent repeated calls', () => {
+      const spy = sinon.spy();
+      class Test {
+        @invokeAtMostOnceForArguments
+        test(obj1: object, obj2: object) {
+          spy(obj1, obj2);
+        }
+      }
+      const t = new Test();
+      expect(spy.callCount).toBe(0);
+      const obj1 = {};
+      const obj2 = {};
+      t.test(obj1, obj2);
+      expect(spy.callCount).toBe(1);
+      expect(spy.lastCall.calledWith(obj1, obj2)).toBeTruthy();
+      t.test(obj1, obj2);
+      expect(spy.callCount).toBe(1);
+      expect(spy.lastCall.calledWith(obj1, obj2)).toBeTruthy();
+      const obj3 = {};
+      t.test(obj1, obj3);
+      expect(spy.callCount).toBe(2);
+      expect(spy.lastCall.calledWith(obj1, obj3)).toBeTruthy();
+    });
+
+    it('should throw an error for dynamic argumetns', () => {
+      class Test {
+        @invokeAtMostOnceForArguments
+        test(..._args: unknown[]) {}
+      }
+      const t = new Test();
+      t.test({});
+      expect(() => {
+        t.test({}, {});
+      }).toThrow();
+    });
+
+    it('should throw an error for non object arguments', () => {
+      class Test {
+        @invokeAtMostOnceForArguments
+        test(..._args: unknown[]) {}
+      }
+      const t = new Test();
+      expect(() => {
+        t.test(1);
+      }).toThrow();
+    });
+  });
+});

packages/puppeteer-core/src/util/decorators.ts

@@ -72,3 +72,44 @@ export function throwIfDisposed<This extends Disposed>(
     };
   };
 }
+
+/**
+ * The decorator only invokes the target if the target has not been invoked with
+ * the same arguments before. The decorated method throws an error if it's
+ * invoked with a different number of elements: if you decorate a method, it
+ * should have the same number of arguments
+ *
+ * @internal
+ */
+export function invokeAtMostOnceForArguments(
+  target: (this: unknown, ...args: any[]) => any,
+  _: unknown
+): typeof target {
+  const cache = new WeakMap();
+  let cacheDepth = -1;
+  return function (this: unknown, ...args: unknown[]) {
+    if (cacheDepth === -1) {
+      cacheDepth = args.length;
+    }
+    if (cacheDepth !== args.length) {
+      throw new Error(
+        'Memoized method was called with the wrong number of arguments'
+      );
+    }
+    let freshArguments = false;
+    let cacheIterator = cache;
+    for (const arg of args) {
+      if (cacheIterator.has(arg as object)) {
+        cacheIterator = cacheIterator.get(arg as object)!;
+      } else {
+        freshArguments = true;
+        cacheIterator.set(arg as object, new WeakMap());
+        cacheIterator = cacheIterator.get(arg as object)!;
+      }
+    }
+    if (!freshArguments) {
+      return;
+    }
+    return target.call(this, ...args);
+  };
+}