fix: allow user gesture restricted code to be run in page.evaluate (#2503)

Fixes #2502

Author: JoelEinbinder

lib/ExecutionContext.js

@@ -64,7 +64,13 @@ class ExecutionContext {
     if (helper.isString(pageFunction)) {
       const contextId = this._contextId;
       const expression = /** @type {string} */ (pageFunction);
-      const { exceptionDetails, result: remoteObject } = await this._client.send('Runtime.evaluate', { expression, contextId, returnByValue: false, awaitPromise: true});
+      const { exceptionDetails, result: remoteObject } = await this._client.send('Runtime.evaluate', {
+        expression,
+        contextId,
+        returnByValue: false,
+        awaitPromise: true,
+        userGesture: true
+      });
       if (exceptionDetails)
         throw new Error('Evaluation failed: ' + helper.getExceptionMessage(exceptionDetails));
       return this._objectHandleFactory(remoteObject);
@@ -75,7 +81,8 @@ class ExecutionContext {
       executionContextId: this._contextId,
       arguments: args.map(convertArgument.bind(this)),
       returnByValue: false,
-      awaitPromise: true
+      awaitPromise: true,
+      userGesture: true
     });
     if (exceptionDetails)
       throw new Error('Evaluation failed: ' + helper.getExceptionMessage(exceptionDetails));

test/page.spec.js

@@ -196,6 +196,18 @@ module.exports.addTests = function({testRunner, expect, puppeteer, DeviceDescrip
       const isFive = await page.evaluate(e => Object.is(e, 5), aHandle);
       expect(isFive).toBeTruthy();
     });
+    it('should simulate a user gesture', async({page, server}) => {
+      await page.evaluate(playAudio);
+      // also test evaluating strings
+      await page.evaluate(`(${playAudio})()`);
+
+      function playAudio() {
+        const audio = document.createElement('audio');
+        audio.src = 'data:audio/wav;base64,UklGRiQAAABXQVZFZm10IBAAAAABAAEARKwAAIhYAQACABAAZGF0YQAAAAA=';
+        // This returns a promise which throws if it was not triggered by a user gesture.
+        return audio.play();
+      }
+    });
   });
 
   describe('Page.setOfflineMode', function() {