error_handler_spec.ts

/**
 * @license
 * Copyright Google Inc. 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 {ERROR_DEBUG_CONTEXT, ERROR_LOGGER, ERROR_TYPE, wrappedError} from '@angular/core/src/util/errors';

import {ErrorHandler} from '../src/error_handler';

class MockConsole {
  res: any[][] = [];
  error(...s: any[]): void { this.res.push(s); }
}

(function() {
  function errorToString(error: any) {
    const logger = new MockConsole();
    const errorHandler = new ErrorHandler();
    (errorHandler as any)._console = logger as any;
    errorHandler.handleError(error);
    return logger.res.map(line => line.join('#')).join('\n');
  }

  describe('ErrorHandler', () => {
    it('should output exception', () => {
      const e = errorToString(new Error('message!'));
      expect(e).toContain('message!');
    });

    describe('context', () => {
      it('should print nested context', () => {
        const cause = new Error('message!');
        const context = { source: 'context!', toString() { return 'Context'; } } as any;
        const original = debugError(cause, context);
        const e = errorToString(wrappedError('message', original));
        expect(e).toEqual(`ERROR#Error: message caused by: Error in context! caused by: message!
ORIGINAL ERROR#Error: message!
ERROR CONTEXT#Context`);
      });
    });

    describe('original exception', () => {
      it('should print original exception message if available (original is Error)', () => {
        const realOriginal = new Error('inner');
        const original = wrappedError('wrapped', realOriginal);
        const e = errorToString(wrappedError('wrappedwrapped', original));
        expect(e).toContain('inner');
      });

      it('should print original exception message if available (original is not Error)', () => {
        const realOriginal = new Error('custom');
        const original = wrappedError('wrapped', realOriginal);
        const e = errorToString(wrappedError('wrappedwrapped', original));
        expect(e).toContain('custom');
      });
    });

    it('should use the error logger on the error', () => {
      const err = new Error('test');
      const console = new MockConsole();
      const errorHandler = new ErrorHandler();
      (errorHandler as any)._console = console as any;
      const logger = jasmine.createSpy('logger');
      (err as any)[ERROR_LOGGER] = logger;

      errorHandler.handleError(err);

      expect(console.res).toEqual([]);
      expect(logger).toHaveBeenCalledWith(console, 'ERROR', err);
    });
  });
})();

function debugError(originalError: any, context: any): Error {
  const error = wrappedError(`Error in ${context.source}`, originalError);
  (error as any)[ERROR_DEBUG_CONTEXT] = context;
  (error as any)[ERROR_TYPE] = debugError;
  return error;
}