feat(rpc): make ElectronApplication a scope (#3159)

src/rpc/channels.ts

@@ -1617,10 +1617,9 @@ export type ElectronLaunchResult = {
 };
 
 // ----------- ElectronApplication -----------
-export type ElectronApplicationInitializer = {
+export type ElectronApplicationInitializer = {};
-  context: BrowserContextChannel,
-};
 export interface ElectronApplicationChannel extends Channel {
+  on(event: 'context', callback: (params: ElectronApplicationContextEvent) => void): this;
   on(event: 'close', callback: (params: ElectronApplicationCloseEvent) => void): this;
   on(event: 'window', callback: (params: ElectronApplicationWindowEvent) => void): this;
   newBrowserWindow(params: ElectronApplicationNewBrowserWindowParams): Promise<ElectronApplicationNewBrowserWindowResult>;
@@ -1628,6 +1627,9 @@ export interface ElectronApplicationChannel extends Channel {
   evaluateExpressionHandle(params: ElectronApplicationEvaluateExpressionHandleParams): Promise<ElectronApplicationEvaluateExpressionHandleResult>;
   close(params?: ElectronApplicationCloseParams): Promise<ElectronApplicationCloseResult>;
 }
+export type ElectronApplicationContextEvent = {
+  context: BrowserContextChannel,
+};
 export type ElectronApplicationCloseEvent = {};
 export type ElectronApplicationWindowEvent = {
   page: PageChannel,

src/rpc/client/channelOwner.ts

@@ -15,10 +15,10 @@
  */
 
 import { EventEmitter } from 'events';
-import { Channel } from '../channels';
+import type { Channel } from '../channels';
-import { Connection } from './connection';
+import type { Connection } from './connection';
 import { assert } from '../../helper';
-import { LoggerSink } from '../../loggerSink';
+import type { LoggerSink } from '../../loggerSink';
 import { DebugLoggerSink } from '../../logger';
 
 export abstract class ChannelOwner<T extends Channel = Channel, Initializer = {}> extends EventEmitter {
@@ -37,11 +37,11 @@ export abstract class ChannelOwner<T extends Channel = Channel, Initializer = {}
 
   constructor(parent: ChannelOwner | Connection, type: string, guid: string, initializer: Initializer, isScope?: boolean) {
     super();
-    this._connection = parent instanceof Connection ? parent : parent._connection;
+    this._connection = parent instanceof ChannelOwner ? parent._connection : parent;
     this._type = type;
     this._guid = guid;
     this._isScope = !!isScope;
-    this._parent = parent instanceof Connection ? undefined : parent;
+    this._parent = parent instanceof ChannelOwner ? parent : undefined;
 
     this._connection._objects.set(guid, this);
     if (this._parent) {

src/rpc/client/connection.ts

@@ -131,8 +131,8 @@ export class Connection {
         break;
       case 'BrowserContext':
         let browserName = '';
-        if (parent instanceof Electron) {
+        if (parent instanceof ElectronApplication) {
-          // Launching electron produces Electron parent for BrowserContext.
+          // Launching electron produces ElectronApplication parent for BrowserContext.
           browserName = 'electron';
         } else if (parent instanceof Browser) {
           // Launching a browser produces Browser parent for BrowserContext.

src/rpc/client/electron.ts

@@ -51,7 +51,7 @@ export class Electron extends ChannelOwner<ElectronChannel, ElectronInitializer>
 }
 
 export class ElectronApplication extends ChannelOwner<ElectronApplicationChannel, ElectronApplicationInitializer> {
-  private _context: BrowserContext;
+  private _context?: BrowserContext;
   private _windows = new Set<Page>();
   private _timeoutSettings = new TimeoutSettings();
 
@@ -60,8 +60,8 @@ export class ElectronApplication extends ChannelOwner<ElectronApplicationChannel
   }
 
   constructor(parent: ChannelOwner, type: string, guid: string, initializer: ElectronApplicationInitializer) {
-    super(parent, type, guid, initializer);
+    super(parent, type, guid, initializer, true);
-    this._context = BrowserContext.from(initializer.context);
+    this._channel.on('context', ({ context }) => this._context = BrowserContext.from(context));
     this._channel.on('window', ({ page, browserWindow }) => {
       const window = Page.from(page);
       (window as any).browserWindow = JSHandle.from(browserWindow);
@@ -71,6 +71,7 @@ export class ElectronApplication extends ChannelOwner<ElectronApplicationChannel
     });
     this._channel.on('close', () => {
       this.emit(ElectronEvents.ElectronApplication.Close);
+      this._dispose();
     });
   }
 
@@ -90,7 +91,7 @@ export class ElectronApplication extends ChannelOwner<ElectronApplicationChannel
   }
 
   context(): BrowserContext {
-    return this._context;
+    return this._context!;
   }
 
   async close() {

src/rpc/protocol.yml

@@ -1887,9 +1887,6 @@ Electron:
 ElectronApplication:
   type: interface
 
-  initializer:
-    context: BrowserContext
-
   commands:
 
     newBrowserWindow:
@@ -1918,6 +1915,11 @@ ElectronApplication:
 
   events:
 
+    # This event happens once immediately after creation.
+    context:
+      parameters:
+        context: BrowserContext
+
     close:
 
     window:

src/rpc/server/electronDispatcher.ts

@@ -41,11 +41,12 @@ export class ElectronDispatcher extends Dispatcher<Electron, ElectronInitializer
 
 export class ElectronApplicationDispatcher extends Dispatcher<ElectronApplication, ElectronApplicationInitializer> implements ElectronApplicationChannel {
   constructor(scope: DispatcherScope, electronApplication: ElectronApplication) {
-    super(scope, electronApplication, 'ElectronApplication', {
+    super(scope, electronApplication, 'ElectronApplication', {}, true);
-      context: new BrowserContextDispatcher(scope, electronApplication.context() as BrowserContextBase),
+    this._dispatchEvent('context', { context: new BrowserContextDispatcher(this._scope, electronApplication.context() as BrowserContextBase) });
+    electronApplication.on(ElectronEvents.ElectronApplication.Close, () => {
+      this._dispatchEvent('close');
+      this._dispose();
     });
-
-    electronApplication.on(ElectronEvents.ElectronApplication.Close, () => this._dispatchEvent('close'));
     electronApplication.on(ElectronEvents.ElectronApplication.Window, (page: ElectronPage) => {
       this._dispatchEvent('window', {
         page: lookupDispatcher<PageDispatcher>(page),