angular-docs-cn/modules/@angular/facade/test/exception_handler_spec.ts

import {beforeEach, ddescribe, describe, expect, iit, inject, it, xdescribe, xit,} from '@angular/core/testing/testing_internal';
import {BaseException, WrappedException, ExceptionHandler} from '../src/exceptions';

class _CustomException {
  context = 'some context';
  toString(): string { return 'custom'; }
}

export function main() {
  describe('ExceptionHandler', () => {
    it('should output exception', () => {
      var e = ExceptionHandler.exceptionToString(new BaseException('message!'));
      expect(e).toContain('message!');
    });

    it('should output stackTrace', () => {
      var e = ExceptionHandler.exceptionToString(new BaseException('message!'), 'stack!');
      expect(e).toContain('stack!');
    });

    it('should join a long stackTrace', () => {
      var e =
          ExceptionHandler.exceptionToString(new BaseException('message!'), ['stack1', 'stack2']);
      expect(e).toContain('stack1');
      expect(e).toContain('stack2');
    });

    it('should output reason when present', () => {
      var e = ExceptionHandler.exceptionToString(new BaseException('message!'), null, 'reason!');
      expect(e).toContain('reason!');
    });

    describe('context', () => {
      it('should print context', () => {
        var e = ExceptionHandler.exceptionToString(
            new WrappedException('message!', null, null, 'context!'));
        expect(e).toContain('context!');
      });

      it('should print nested context', () => {
        var original = new WrappedException('message!', null, null, 'context!');
        var e = ExceptionHandler.exceptionToString(new WrappedException('message', original));
        expect(e).toContain('context!');
      });

      it('should not print context when the passed-in exception is not a BaseException', () => {
        var e = ExceptionHandler.exceptionToString(new _CustomException());
        expect(e).not.toContain('context');
      });
    });

    describe('original exception', () => {
      it('should print original exception message if available (original is BaseException)', () => {
        var realOriginal = new BaseException('inner');
        var original = new WrappedException('wrapped', realOriginal);
        var e =
            ExceptionHandler.exceptionToString(new WrappedException('wrappedwrapped', original));
        expect(e).toContain('inner');
      });

      it('should print original exception message if available (original is not BaseException)',
         () => {
           var realOriginal = new _CustomException();
           var original = new WrappedException('wrapped', realOriginal);
           var e =
               ExceptionHandler.exceptionToString(new WrappedException('wrappedwrapped', original));
           expect(e).toContain('custom');
         });
    });

    describe('original stack', () => {
      it('should print original stack if available', () => {
        var realOriginal = new BaseException('inner');
        var original = new WrappedException('wrapped', realOriginal, 'originalStack');
        var e = ExceptionHandler.exceptionToString(
            new WrappedException('wrappedwrapped', original, 'wrappedStack'));
        expect(e).toContain('originalStack');
      });
    });
  });
}