'use strict';
const chai = require('chai');
const sinon = require('sinon');
const index = require('./index');
const myModule = require('./myModule'); // Require normally the module to stub

const expect = chai.expect;

describe('test for sinon', () => {
  let stubMyModuleMyFunction;

  beforeEach(() => {
    stubMyModuleMyFunction = sinon.stub(myModule, 'myFunction'); // Stub the function in beforeEach hook of mocha to avoid side effect between tests
  });

  afterEach(() => {
    stubMyModuleMyFunction.restore(); // Always restore the stub in the afterEach hook
  });

  it('should fail', (done) => {
    stubMyModuleMyFunction.yields(new Error('KO')); // Stub with sinon can either return something or call the first callback it receives (with yields)
    index.handler(payload, context, (err, data) => {
      try {
        expect(err.message).to.equal('myFunction failed with message : KO');
        expect(stubMyModuleMyFunction.called).to.be.true; // All sinon stub are also spies
        done();
      } catch (e) {
        done(e);
      }
    });
  });
});