The example provided for Jasmine test 101 in Angular2 and TypeScript fails to function when the class is annotated with @Pipe

I have been attempting to configure Jasmine tests based on the official Angular 2 documentation found at https://angular.io/docs/ts/latest/guide/testing.html. However, I am facing issues with the Pipe Testing example provided in the documentation. When running the tests, only the specifications for Hero seem to be working and displaying results in the browser.

If I remove the Pipe annotation, the tests start functioning:

import { Pipe, PipeTransform } from '@angular/core';
//@Pipe({ name: 'my-uppercase' })
export class MyUppercasePipe implements PipeTransform {
  transform(value: string) {
    return value;
  }
}

Can someone assist me in figuring out what additional steps need to be taken in order for the tests to work effectively with pipe annotations? The modified code post following the tutorial can be accessed here - https://github.com/rohans84/quickstart

Answer №1

I have found success with the configuration below.

Pipe

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({
  name: 'sample'
})
export class SamplePipe implements PipeTransform {

  transform(value: any, args?: any): any {
    return null;
  }

}

Spec

import { SamplePipe } from './sample.pipe';

describe('Pipe: Sample', () => {
  it('create an instance', () => {
    let pipe = new SamplePipe();
    expect(pipe).toBeTruthy();
  });
});

Testing Guide

The testing guide may need updating. Reference for this can be found at https://angular.io/docs/ts/latest/guide/testing.html

[EDIT]

I utilize Karma to execute my tests. I have established a procedure for running Tests on GitHub: http://github.com/GregOnNet/angular2-testing-playground

I rely on angular-cli for managing my Angular 2 projects.

Hopefully, this information proves useful

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