Function patchJest

packages/zone.js/lib/jest/jest.ts:14–315

(Zone: ZoneType)

declare let jest: any;

export function patchJest(Zone: ZoneType): void {
  Zone.__load_patch('jest', (context: any, Zone: ZoneType, api: _ZonePrivate) => {
    if (typeof jest === 'undefined' || jest['__zone_patch__']) {
      return;
    }

    // From jest 29 and jest-preset-angular v13, the module transform logic
    // changed, and now jest-preset-angular use the use the tsconfig target
    // other than the hardcoded one, https://github.com/thymikee/jest-preset-angular/issues/2010
    // But jest-angular-preset doesn't introduce the @babel/plugin-transform-async-to-generator
    // which is needed by angular since `async/await` still need to be transformed
    // to promise for ES2017+ target.
    // So for now, we disable to output the uncaught error console log for a temp solution,
    // until jest-preset-angular find a proper solution.
    (Zone as any)[api.symbol('ignoreConsoleErrorUncaughtError')] = true;
    jest['__zone_patch__'] = true;

    const ProxyZoneSpec = (Zone as any)['ProxyZoneSpec'];
    const SyncTestZoneSpec = (Zone as any)['SyncTestZoneSpec'];

    if (!ProxyZoneSpec) {
      throw new Error('Missing ProxyZoneSpec');
    }

    const rootZone = Zone.current;
    const syncZone = rootZone.fork(new SyncTestZoneSpec('jest.describe'));
    const proxyZoneSpec = new ProxyZoneSpec();
    const proxyZone = rootZone.fork(proxyZoneSpec);

    function wrapDescribeFactoryInZone(originalJestFn: Function) {
      return function (this: unknown, ...tableArgs: any[]) {
        const originalDescribeFn = originalJestFn.apply(this, tableArgs);
        return function (this: unknown, ...args: any[]) {
          args[1] = wrapDescribeInZone(args[1]);
          return originalDescribeFn.apply(this, args);
        };
      };
    }

    function wrapTestFactoryInZone(originalJestFn: Function) {
      return function (this: unknown, ...tableArgs: any[]) {
        return function (this: unknown, ...args: any[]) {
          args[1] = wrapTestInZone(args[1]);
          return originalJestFn.apply(this, tableArgs).apply(this, args);
        };
      };
    }

    /**
     * Gets a function wrapping the body of a jest `describe` block to execute in a
     * synchronous-only zone.
     */
    function wrapDescribeInZone(describeBody: Function): Function {
      return function (this: unknown, ...args: any[]) {
        return syncZone.run(describeBody, this, args);
      };
    }