JestExample.js

import { util } from '../helpers/utils';

describe('test cases for the exported util object', () => {
  test('exported object to be defined', () => {
    expect(util).toBeDefined();
  });
  test('util should be an object', () => {
    expect(typeof util).toBe('object');
  });
});

describe('test cases for parseHeader', () => {
  test('should be defined', () => {
    expect(util.parseHeader).toBeDefined();
  });
  test('should return null if no requestHeader prop passed', () => {
    const output = util.parseHeader();
    expect(output).toBeNull();
  });
  test('should return the value of the header', () => {
    const headerName = 'Retry-Time';
    const expectedRetryTime = 3600;
    const requestObject = {
      headers: {
        [headerName]: expectedRetryTime
      }
    };
    const output = util.parseHeader(requestObject, headerName);
    expect(output).toBe(expectedRetryTime);
  });
});