I'm not able to test my sails.js controller with chai and sinon - unit-testing

Question

I have a controller Acounts with a method sum, and a service file named validation with an object register. This object has a method validate that validates the form provided and returns a Boolean.
Controller
sum: function(req, res) {
//validate form with a validation service function
const validator = new validation.register();
let check = validator.validate(req.body.form);
let count = 0;
if (check) {
count += 1;
} else {
count -= 1;
}
res.send(count);
},
test
//imports
const chai = require("chai");
const expect = chai.expect;
const sinon = require("sinon");
const util = require('util'); // to print complex objects
const acountsC = require("../../../api/controllers/AcountsController.js");
describe("AcountsController", function() {
describe("sum", function() {
let req = {
body: {
form: {}
}
}
let res = {
send: sinon.spy()
}
let validation = {
register: {
validate: function() {}
}
}
let stub_validate = sinon.stub(validation.register, "validate").returns(true);
it("count should be 1 when validation is true", function() {
acountsC.sum(req, res);
expect(count).to.equal(1);
});
});
});
test log
AcountsController
sum
1) count should be 1 when validation is true
0 passing (5s)
1 failing
1) AcountsController
sum
count should be 1 when validation is true:
ReferenceError: count is not defined
note
I understand that the test is supposed to execute the piece of code we are calling, while replacing the external functions called in that piece of code(The controller) making it return whatever we set. If the test is executing that piece of code, why I can't access any variables created in the controller?
I've tried by spying res.send(), and check if it was called with a 1. I didn't succeed.
I searched everywhere how to perform an assertion to a variable, but I found nothing. :(
hope you can help

Answer 1

Here is the unit test solution:
accountController.js:
const validation = require('./validation');
class AccountController {
sum(req, res) {
const validator = new validation.register();
const check = validator.validate(req.body.form);
let count = 0;
if (check) {
count += 1;
} else {
count -= 1;
}
res.send(count);
}
}
module.exports = AccountController;
validation.js:
class Register {
validate() {}
}
module.exports = {
register: Register,
};
accountController.test.js:
const AccountController = require('./accountController');
const sinon = require('sinon');
const validation = require('./validation');
describe('60182912', () => {
afterEach(() => {
sinon.restore();
});
describe('#sum', () => {
it('should increase count and send', () => {
const registerInstanceStub = {
validate: sinon.stub().returns(true),
};
const registerStub = sinon.stub(validation, 'register').callsFake(() => registerInstanceStub);
const accountController = new AccountController();
const mRes = { send: sinon.stub() };
const mReq = { body: { form: {} } };
accountController.sum(mReq, mRes);
sinon.assert.calledWithExactly(mRes.send, 1);
sinon.assert.calledOnce(registerStub);
sinon.assert.calledWithExactly(registerInstanceStub.validate, {});
});
it('should decrease count and send', () => {
const registerInstanceStub = {
validate: sinon.stub().returns(false),
};
const registerStub = sinon.stub(validation, 'register').callsFake(() => registerInstanceStub);
const accountController = new AccountController();
const mRes = { send: sinon.stub() };
const mReq = { body: { form: {} } };
accountController.sum(mReq, mRes);
sinon.assert.calledWithExactly(mRes.send, -1);
sinon.assert.calledOnce(registerStub);
sinon.assert.calledWithExactly(registerInstanceStub.validate, {});
});
});
});
Unit test results with coverage report:
60182912
#sum
✓ should increase count and send
✓ should decrease count and send
2 passing (10ms)
----------------------|---------|----------|---------|---------|-------------------
File | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s
----------------------|---------|----------|---------|---------|-------------------
All files | 100 | 100 | 50 | 100 |
accountController.js | 100 | 100 | 100 | 100 |
validation.js | 100 | 100 | 0 | 100 |
----------------------|---------|----------|---------|---------|-------------------
source code: https://github.com/mrdulin/expressjs-research/tree/master/src/stackoverflow/60182912

Answer 2

The problem was the lifecycle file I created trusting in sails docs. That documentation is for integrated testing due to the fact that it lifts sails before any other test. This is quite slow while unit tests should be fast. Erasing that file was enough to test the controller successfully. Otherwise sails messes up with the tests in a way I don't even fully understand. I suppose it is due to sails making services globally available. So when my controller calls for validation service, this one returns some default and not what the stub says it should return.
UPDATE:
I managed to make it work. When lifting sails before testing, only the tested controller should be require, services and models shouldn't.