How do I mock the request in this function. I want to unit test this function using jasmine.
function getProducts() {
return new Promise((resolve, reject) => {
request.get(
{
url: 'http://ascott.com/products'
},
(err, response, body) => {
if (err) return reject(err);
const result = JSON.parse(body);
if(result.value =='yes') return resolve(1);
return resolve(0);
}
);
});
}
Use spyOn(obj, methodName) function to install a spy onto request.get() method, then use callFake(fn) tell the spy to call a fake implementation when invoked. So that you can trigger the callback in the fake implementation.
index.js:
import request from 'request';
export function getProducts() {
return new Promise((resolve, reject) => {
request.get({ url: 'http://ascott.com/products' }, (err, response, body) => {
if (err) return reject(err);
const result = JSON.parse(body);
if (result.value == 'yes') return resolve(1);
return resolve(0);
});
});
}
index.test.js:
import { getProducts } from '.';
import request from 'request';
describe('69769551', () => {
it('should return 1', async () => {
spyOn(request, 'get').and.callFake((_, callback) => {
callback(null, null, JSON.stringify({ value: 'yes' }));
});
const actual = await getProducts();
expect(actual).toEqual(1);
});
it('should throw error', async () => {
const mError = new Error('network');
spyOn(request, 'get').and.callFake((_, callback) => {
callback(mError);
});
await expectAsync(getProducts()).toBeRejectedWithError('network');
});
});
test result:
Executing 2 defined specs...
Running in random order... (seed: 04537)
Test Suites & Specs:
1. 69769551
โ should throw error (7ms)
โ should return 1 (1ms)
>> Done!
Summary:
๐ Passed
Suites: 1 of 1
Specs: 2 of 2
Expects: 2 (0 failures)
Finished in 0.017 seconds
package versions:
"jasmine": "^3.6.3"
"request": "^2.88.2"