fix(reuse): ignore late bindings after dispatchers were disposed (#22838)

When reusing the context, we first dispose all dispatchers, and then
reset the page/context. If bindings are triggered during the reset, they
try to send messages on disposed dispatchers.

Since there is no way to unregister bindings, just ignore them after
disposal.

Fixes #22803.

packages/playwright-core/src/server/dispatchers/browserContextDispatcher.ts

@@ -169,6 +169,10 @@ export class BrowserContextDispatcher extends Dispatcher<BrowserContext, channel
 
   async exposeBinding(params: channels.BrowserContextExposeBindingParams): Promise<void> {
     await this._context.exposeBinding(params.name, !!params.needsHandle, (source, ...args) => {
+      // When reusing the context, we might have some bindings called late enough,
+      // after context and page dispatchers have been disposed.
+      if (this._disposed)
+        return;
       const pageDispatcher = PageDispatcher.from(this, source.page);
       const binding = new BindingCallDispatcher(pageDispatcher, params.name, !!params.needsHandle, source, args);
       this._dispatchEvent('bindingCall', { binding });

packages/playwright-core/src/server/dispatchers/pageDispatcher.ts

@@ -111,6 +111,10 @@ export class PageDispatcher extends Dispatcher<Page, channels.PageChannel, Brows
 
   async exposeBinding(params: channels.PageExposeBindingParams, metadata: CallMetadata): Promise<void> {
     await this._page.exposeBinding(params.name, !!params.needsHandle, (source, ...args) => {
+      // When reusing the context, we might have some bindings called late enough,
+      // after context and page dispatchers have been disposed.
+      if (this._disposed)
+        return;
       const binding = new BindingCallDispatcher(this, params.name, !!params.needsHandle, source, args);
       this._dispatchEvent('bindingCall', { binding });
       return binding.promise();

tests/library/browsercontext-reuse.spec.ts

@@ -182,3 +182,23 @@ test('should not cache resources', async ({ reusedContext, server }) => {
     expect(requestCountMap.get('/simple.json')).toBe(2);
   }
 });
+
+test('should ignore binding from beforeunload', async ({ reusedContext }) => {
+  test.info().annotations.push({ type: 'issue', description: 'https://github.com/microsoft/playwright/issues/22803' });
+
+  let context = await reusedContext();
+
+  let called = false;
+  await context.exposeFunction('binding', () => called = true);
+
+  let page = await context.newPage();
+  await page.evaluate(() => {
+    window.addEventListener('beforeunload', () => window['binding']());
+  });
+
+  context = await reusedContext();
+  page = context.pages()[0];
+  await page.setContent('hello');
+
+  expect(called).toBe(false);
+});