Basic testing with Angular Schematics

index_spec.ts

import { Tree } from '@angular-devkit/schematics';
import { SchematicTestRunner } from '@angular-devkit/schematics/testing';
import * as path from 'path';

const collectionPath = path.join(__dirname, '../collection.json');

describe('hello', () => {
  it('Execute with default args', async () => {
    const runner = new SchematicTestRunner('schematics', collectionPath);
    const tree = await runner
      .runSchematicAsync('hello', {}, Tree.empty())
      .toPromise();

    expect(tree.files.length).toEqual(1);
    expect(tree.files[0]).toEqual('/hello-helloanartz--1.js');
  });

  it('Execute with default age and name value input', async () => {
    const runner = new SchematicTestRunner('schematics', collectionPath);
    const treeNameAnartz = await runner
      .runSchematicAsync('hello', {
        name: 'anartz'
      }, Tree.empty())
      .toPromise();

    expect(treeNameAnartz.files.length).toEqual(1);
    expect(treeNameAnartz.files[0]).toEqual('/hello-anartz--1.js');

    const treeNameMikel = await runner
      .runSchematicAsync('hello', {
        name: 'Mikel'
      }, Tree.empty())
      .toPromise();

    expect(treeNameMikel.files.length).toEqual(1);
    expect(treeNameMikel.files[0]).toEqual('/hello-mikel--1.js');
  });

  it('Execute with default name and age value input', async () => {
    const runner = new SchematicTestRunner('schematics', collectionPath);
    const treeFiftySix = await runner
      .runSchematicAsync('hello', {
        age: '56'
      }, Tree.empty())
      .toPromise();

    expect(treeFiftySix.files.length).toEqual(1);
    expect(treeFiftySix.files[0]).toEqual('/hello-helloanartz-56.js');

    const treeNameMikel = await runner
      .runSchematicAsync('hello', {
        name: 'Mikel'
      }, Tree.empty())
      .toPromise();

    expect(treeNameMikel.files.length).toEqual(1);
    expect(treeNameMikel.files[0]).toEqual('/hello-mikel--1.js');
  });

  it('Execute and check content is correct', async () => {
    const runner = new SchematicTestRunner('schematics', collectionPath);
    const tree = await runner
      .runSchematicAsync('hello', {}, Tree.empty())
      .toPromise();

      console.log(tree.files);
      expect(tree.readContent(tree.files[0]))
      .toContain(
        "console.log('¡Hola HelloAnartz!Veo que tienes -1 años ;)')"
      );
  })
});