JestJS

Lib de testes para Javascript e Typescript

URL: https://jestjs.io

Uso

Exemplo básico

beforeEach(() => {
  initializeCityDatabase();
});
 
afterEach(() => {
  clearCityDatabase();
});
 
test('city database has Vienna', () => {
  expect(isCity('Vienna')).toBeTruthy();
});
 
test('city database has San Juan', () => {
  expect(isCity('San Juan')).toBeTruthy();
});

Mock de módulos

https://jestjs.io/docs/jest-object#jestmockmodulename-factory-options

jest.mock('./typeOrm.config', () => ({
  __esModule: true, // this property makes it work as a module
  default: {
    // initialize method of an object exported at typeOrm
    initialize: jest.fn(),
  },
  // Retain the actual implementation
  postgresSettings: jest.requireActual('./typeOrm.config').postgresSettings,
}));

typeOrm.config.ts:

import { join } from 'path'
import { DataSource } from 'typeorm'
import { config } from 'dotenv'
 
config()
 
export const postgresSettings = {
  host: process.env.POSTGRES_HOST,
  port: 5432,
  username: process.env.POSTGRES_USER,
  password: process.env.POSTGRES_PASSWORD,
  database: process.env.POSTGRES_DB,
}
 
export default new DataSource({
  type: 'postgres',
  host: postgresSettings.host,
  port: 5432,
  username: postgresSettings.username,
  password: postgresSettings.password,
  database: postgresSettings.database,
  entities: [join(__dirname, '../', '**', '*.entity.{ts,js}')],
  migrations: [__dirname + '/migrations/*.ts'],
  migrationsRun: true,
})
 
// DataSource has a method called initialize()
 

Table tests

const { extractUrls } = require("../src/extractUrls");
 
describe("extractUrls (Table-driven tests array format)", () => {
  it.each([
    ["Go to https://knowledge.com", ["https://knowledge.com"]],
    [
      "Go to https://knowledge.com and https://world.org",
      ["https://knowledge.com", "https://world.org"],
    ],
    ["Go to http://knowledge.com", ["http://knowledge.com"]],
    ["Go to google.com", ["google.com"]],
  ])("extractUrls(%s)", (message, expectedUrls) => {
    const extractedUrls = extractUrls(message);
 
    expect(extractedUrls).toEqual(expectedUrls);
  });
});

Rodando testes específicos (padrão)

Use --testPathPattern para dar match no nome do arquivo (aceita wildcard *) Use -t para dar match no nome do teste

Exemplo:

--testPathPattern=item_processor -t "repository with expected params"