From 060fbf74281e37bb4f7dc9d13627c0cb9f878c68 Mon Sep 17 00:00:00 2001
From: Dmitry Gozman <dgozman@gmail.com>
Date: Thu, 23 Jan 2020 17:52:06 -0800
Subject: [PATCH] fix(workers): emit workerdestroyed event when clearing
 workers (#618)

---
 src/page.ts          |  5 ++++-
 test/workers.spec.js | 15 +++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/src/page.ts b/src/page.ts
index 52b885109c77e..951b66b95a1bf 100644
--- a/src/page.ts
+++ b/src/page.ts
@@ -520,7 +520,10 @@ export class Page extends platform.EventEmitter {
   }
 
   _clearWorkers() {
-    this._workers.clear();
+    for (const [workerId, worker] of this._workers) {
+      this.emit(Events.Page.WorkerDestroyed, worker);
+      this._workers.delete(workerId);
+    }
   }
 }
 
diff --git a/test/workers.spec.js b/test/workers.spec.js
index b810a136c6478..726563c7f2e61 100644
--- a/test/workers.spec.js
+++ b/test/workers.spec.js
@@ -80,7 +80,22 @@ module.exports.describe = function({testRunner, expect, FFOX, CHROMIUM, WEBKIT})
       page.evaluate(() => new Worker(URL.createObjectURL(new Blob(['console.log(1)'], {type: 'application/javascript'}))));
       await workerCreatedPromise;
       expect(page.workers().length).toBe(1);
+      let destroyed = false;
+      page.once('workerdestroyed', () => destroyed = true);
+      await page.goto(server.PREFIX + '/one-style.html');
+      expect(destroyed).toBe(true);
+      expect(page.workers().length).toBe(0);
+    });
+    it('should clear upon cross-process navigation', async function({server, page}) {
+      await page.goto(server.EMPTY_PAGE);
+      const workerCreatedPromise = page.waitForEvent('workercreated');
+      page.evaluate(() => new Worker(URL.createObjectURL(new Blob(['console.log(1)'], {type: 'application/javascript'}))));
+      await workerCreatedPromise;
+      expect(page.workers().length).toBe(1);
+      let destroyed = false;
+      page.once('workerdestroyed', () => destroyed = true);
       await page.goto(server.CROSS_PROCESS_PREFIX + '/empty.html');
+      expect(destroyed).toBe(true);
       expect(page.workers().length).toBe(0);
     });
     it('should report network activity', async function({page, server}) {