ref(angular): Set ErrorHandler Exception Mechanism to be unhandled by default(#3844)

Previously, exceptions caught in the Sentry `ErrorHandler` defaulted to the generic mechanism, meaning they were marked as `handled: true` and `mechanism: generic`. This patch adds a custom mechanism for these events: `handled: false` (because they were caught in our ErrorHandler) and `mechanism: angular`.

Author: onurtemizkan

packages/angular/src/errorhandler.ts

@@ -1,6 +1,8 @@
 import { HttpErrorResponse } from '@angular/common/http';
 import { ErrorHandler as AngularErrorHandler, Inject, Injectable } from '@angular/core';
 import * as Sentry from '@sentry/browser';
+import { captureException } from '@sentry/browser';
+import { addExceptionMechanism } from '@sentry/utils';
 
 import { runOutsideAngular } from './zone';
 
@@ -40,7 +42,20 @@ class SentryErrorHandler implements AngularErrorHandler {
     const extractedError = this._extractError(error) || 'Handled unknown error';
 
     // Capture handled exception and send it to Sentry.
-    const eventId = runOutsideAngular(() => Sentry.captureException(extractedError));
+    const eventId = runOutsideAngular(() =>
+      captureException(extractedError, scope => {
+        scope.addEventProcessor(event => {
+          addExceptionMechanism(event, {
+            type: 'angular',
+            handled: false,
+          });
+
+          return event;
+        });
+
+        return scope;
+      }),
+    );
 
     // When in development mode, log the error to console for immediate feedback.
     if (this._options.logErrors) {

packages/angular/test/errorhandler.test.ts

@@ -0,0 +1,124 @@
+import { HttpErrorResponse } from '@angular/common/http';
+import * as SentryBrowser from '@sentry/browser';
+import { Scope } from '@sentry/browser';
+import * as SentryUtils from '@sentry/utils';
+
+import { createErrorHandler, SentryErrorHandler } from '../src/errorhandler';
+
+const FakeScope = new Scope();
+
+jest.mock('@sentry/browser', () => {
+  const original = jest.requireActual('@sentry/browser');
+  return {
+    ...original,
+    captureException: (err: unknown, cb: (arg0?: unknown) => unknown) => {
+      cb(FakeScope);
+      return original.captureException(err, cb);
+    },
+  };
+});
+
+const captureExceptionSpy = jest.spyOn(SentryBrowser, 'captureException');
+
+jest.spyOn(console, 'error').mockImplementation();
+
+describe('SentryErrorHandler', () => {
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  it('`createErrorHandler `creates a SentryErrorHandler with an empty config', () => {
+    const errorHandler = createErrorHandler();
+
+    expect(errorHandler).toBeInstanceOf(SentryErrorHandler);
+  });
+
+  it('handleError method assigns the correct mechanism', () => {
+    const addEventProcessorSpy = jest.spyOn(FakeScope, 'addEventProcessor').mockImplementationOnce(callback => {
+      void callback({}, { event_id: 'fake-event-id' });
+      return FakeScope;
+    });
+
+    const addExceptionMechanismSpy = jest.spyOn(SentryUtils, 'addExceptionMechanism');
+
+    const errorHandler = createErrorHandler();
+    errorHandler.handleError(new Error('test'));
+
+    expect(addEventProcessorSpy).toBeCalledTimes(1);
+    expect(addExceptionMechanismSpy).toBeCalledTimes(1);
+    expect(addExceptionMechanismSpy).toBeCalledWith({}, { handled: false, type: 'angular' });
+  });
+
+  it('handleError method extracts `null` error', () => {
+    createErrorHandler().handleError(null);
+
+    expect(captureExceptionSpy).toHaveBeenCalledTimes(1);
+    expect(captureExceptionSpy).toHaveBeenCalledWith('Handled unknown error', expect.any(Function));
+  });
+
+  it('handleError method extracts `undefined` error', () => {
+    createErrorHandler().handleError(undefined);
+
+    expect(captureExceptionSpy).toHaveBeenCalledTimes(1);
+    expect(captureExceptionSpy).toHaveBeenCalledWith('Handled unknown error', expect.any(Function));
+  });
+
+  it('handleError method extracts a string', () => {
+    const str = 'sentry-test';
+    createErrorHandler().handleError(str);
+
+    expect(captureExceptionSpy).toHaveBeenCalledTimes(1);
+    expect(captureExceptionSpy).toHaveBeenCalledWith(str, expect.any(Function));
+  });
+
+  it('handleError method extracts an empty Error', () => {
+    const err = new Error();
+    createErrorHandler().handleError(err);
+
+    expect(captureExceptionSpy).toHaveBeenCalledTimes(1);
+    expect(captureExceptionSpy).toHaveBeenCalledWith(err, expect.any(Function));
+  });
+
+  it('handleError method extracts an Error with `ngOriginalError`', () => {
+    const ngErr = new Error('sentry-ng-test');
+    const err = {
+      ngOriginalError: ngErr,
+    };
+
+    createErrorHandler().handleError(err);
+
+    expect(captureExceptionSpy).toHaveBeenCalledTimes(1);
+    expect(captureExceptionSpy).toHaveBeenCalledWith(ngErr, expect.any(Function));
+  });
+
+  it('handleError method extracts an `HttpErrorResponse` with `Error`', () => {
+    const httpErr = new Error('sentry-http-test');
+    const err = new HttpErrorResponse({ error: httpErr });
+
+    createErrorHandler().handleError(err);
+
+    expect(captureExceptionSpy).toHaveBeenCalledTimes(1);
+    expect(captureExceptionSpy).toHaveBeenCalledWith(httpErr, expect.any(Function));
+  });
+
+  it('handleError method extracts an `HttpErrorResponse` with `ErrorEvent`', () => {
+    const httpErr = new ErrorEvent('http', { message: 'sentry-http-test' });
+    const err = new HttpErrorResponse({ error: httpErr });
+
+    createErrorHandler().handleError(err);
+
+    expect(captureExceptionSpy).toHaveBeenCalledTimes(1);
+    expect(captureExceptionSpy).toHaveBeenCalledWith('sentry-http-test', expect.any(Function));
+  });
+
+  it('handleError method extracts an `HttpErrorResponse` with string', () => {
+    const err = new HttpErrorResponse({ error: 'sentry-http-test' });
+    createErrorHandler().handleError(err);
+
+    expect(captureExceptionSpy).toHaveBeenCalledTimes(1);
+    expect(captureExceptionSpy).toHaveBeenCalledWith(
+      'Server returned code 0 with body "sentry-http-test"',
+      expect.any(Function),
+    );
+  });
+});