test(angular): Increase Angular SDK Test Coverage. (#5790)

Increase unit test coverage of Angular SDK by integrating [`TestBed`](https://angular.io/api/core/testing/TestBed).

The main work here is done on [`tracing.ts`](https://github.com/getsentry/sentry-javascript/blob/12c19d051eca4fcef316ba6ee512f1221ae92ef0/packages/angular/src/tracing.ts) which had low test coverage, and the previous tests were [faking the angular router](https://github.com/getsentry/sentry-javascript/blob/12c19d051eca4fcef316ba6ee512f1221ae92ef0/packages/angular/test/tracing.test.ts#L72-L79).

I attempted to use `@testing-library/angular` to be consistent with other SDK tests like `@sentry/react` and `@sentry/svelte`, but it was not possible as [it doesn't support renders without compiled components](https://github.com/testing-library/angular-testing-library/blob/36648c4b431a9e17efa1f59cc2d83710c17a42ee/projects/testing-library/src/lib/testing-library.ts#L43-L89) which we need while testing [`TraceService`](https://github.com/getsentry/sentry-javascript/pull/5790/files#diff-d46ba52093e0179db0bc8dfa1887658374319ebf783602153a45f0e4f4b06e72R55-R72).

Author: onurtemizkan

packages/angular/.eslintrc.js

@@ -3,4 +3,5 @@ module.exports = {
     browser: true,
   },
   extends: ['../../.eslintrc.js'],
+  ignorePatterns: ['setup-jest.ts'],
 };

packages/angular/jest.config.js

@@ -3,4 +3,5 @@ const baseConfig = require('../../jest/jest.config.js');
 module.exports = {
   ...baseConfig,
   testEnvironment: 'jsdom',
+  setupFilesAfterEnv: ['<rootDir>/setup-jest.ts'],
 };

packages/angular/package.json

@@ -33,9 +33,12 @@
     "@angular/compiler": "^10.2.5",
     "@angular/compiler-cli": "~10.2.5",
     "@angular/core": "~10.2.5",
+    "@angular/platform-browser": "~10.2.5",
+    "@angular/platform-browser-dynamic": "~10.2.5",
     "@angular/router": "~10.2.5",
     "ng-packagr": "^10.1.0",
-    "typescript": "~4.0.2"
+    "typescript": "~4.0.2",
+    "zone.js": "^0.11.8"
   },
   "scripts": {
     "build": "yarn build:ngc",

packages/angular/setup-jest.ts

@@ -0,0 +1,7 @@
+import 'zone.js';
+
+import { TestBed } from '@angular/core/testing';
+import { BrowserDynamicTestingModule, platformBrowserDynamicTesting } from '@angular/platform-browser-dynamic/testing';
+
+TestBed.resetTestEnvironment();
+TestBed.initTestEnvironment(BrowserDynamicTestingModule, platformBrowserDynamicTesting());

packages/angular/test/errorhandler.test.ts

@@ -121,4 +121,28 @@ describe('SentryErrorHandler', () => {
       expect.any(Function),
     );
   });
+
+  it('handleError method shows report dialog', () => {
+    const showReportDialogSpy = jest.spyOn(SentryBrowser, 'showReportDialog');
+
+    const errorHandler = createErrorHandler({ showDialog: true });
+    errorHandler.handleError(new Error('test'));
+
+    expect(showReportDialogSpy).toBeCalledTimes(1);
+  });
+
+  it('handleError method extracts error with a custom extractor', () => {
+    const customExtractor = (error: unknown) => {
+      if (typeof error === 'string') {
+        return new Error(`custom ${error}`);
+      }
+      return error;
+    };
+
+    const errorHandler = createErrorHandler({ extractor: customExtractor });
+    errorHandler.handleError('error');
+
+    expect(captureExceptionSpy).toHaveBeenCalledTimes(1);
+    expect(captureExceptionSpy).toHaveBeenCalledWith(new Error('custom error'), expect.any(Function));
+  });
 });