JiaLiPassion 008eaf3b7d fix(zone.js): should continue to executue listeners when throw error (#41562)
Close #41522

`zone.js` patches event listeners and run all event listeners together, if
one event handler throws error, the listeners afterward may not be invoked.

Reproduction:

```
export class AppComponent implements AfterViewInit {
  @ViewChild('btn') btn: ElementRef;
  title = 'event-error';

  constructor(private ngZone: NgZone) {}

  ngAfterViewInit() {
    this.ngZone.runOutsideAngular(() => {
      this.btn.nativeElement.addEventListener('click', () => {
        throw new Error('test1');
      });
      this.btn.nativeElement.addEventListener('click', () => {
        console.log('add eventlistener click');
      });
    });
  }
}
```

Until now no Angular users report this issue becuase in the `ngZone`, all
error will be caught and will not rethrow, so the event listeners afterward
will still continue to execute, but if the event handlers are outside of `ngZone`,
the error will break the execution.

This commit catch all errors, and after all event listeners finished invocation,
rethrow the errors in seperate `microTasks`, the reason I am using `microTask` here
is to handle multiple errors case.

PR Close #41562
2021-04-21 15:54:08 -07:00

66 lines
1.8 KiB
TypeScript

/**
* @license
* Copyright Google LLC All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {patchEventTarget} from '../common/events';
Zone.__load_patch('EventEmitter', (global: any, Zone: ZoneType, api: _ZonePrivate) => {
// For EventEmitter
const EE_ADD_LISTENER = 'addListener';
const EE_PREPEND_LISTENER = 'prependListener';
const EE_REMOVE_LISTENER = 'removeListener';
const EE_REMOVE_ALL_LISTENER = 'removeAllListeners';
const EE_LISTENERS = 'listeners';
const EE_ON = 'on';
const EE_OFF = 'off';
const compareTaskCallbackVsDelegate = function(task: any, delegate: any) {
// same callback, same capture, same event name, just return
return task.callback === delegate || task.callback.listener === delegate;
};
const eventNameToString = function(eventName: string|Symbol) {
if (typeof eventName === 'string') {
return eventName;
}
if (!eventName) {
return '';
}
return eventName.toString().replace('(', '_').replace(')', '_');
};
function patchEventEmitterMethods(obj: any) {
const result = patchEventTarget(global, api, [obj], {
useG: false,
add: EE_ADD_LISTENER,
rm: EE_REMOVE_LISTENER,
prepend: EE_PREPEND_LISTENER,
rmAll: EE_REMOVE_ALL_LISTENER,
listeners: EE_LISTENERS,
chkDup: false,
rt: true,
diff: compareTaskCallbackVsDelegate,
eventNameToString: eventNameToString
});
if (result && result[0]) {
obj[EE_ON] = obj[EE_ADD_LISTENER];
obj[EE_OFF] = obj[EE_REMOVE_LISTENER];
}
}
// EventEmitter
let events;
try {
events = require('events');
} catch (err) {
}
if (events && events.EventEmitter) {
patchEventEmitterMethods(events.EventEmitter.prototype);
}
});