Best practice for decoupling queries from testing

Question

I'm looking for best practices for testing mysql queries with mocha or sinon. I'm trying to test very basic DB queries such as save:

User.prototype.save = function(cb) {

var query = 'INSERT INTO user (name, email, password, img, description)' 
    + 'values (?, ?, ?, ?, ?)';

var params = [this.name, this.email, this.pass, this.img, this.description];

db.query(query, 
    params,
    function(err, rows) {
        if (err) return cb(err);
        cb(rows.insertId);
    }
);
};

I believe I want to make a mock of the database and use that object instead of my db object, but I also want to separate the test logic from the application logic.

I tried variations along the lines of

describe('User', function() {
before(function() {
    mock = sinon.mock(require('../middleware/db'));
})
describe('.save()', function() {
    var uid;
    it('should run save on a user', function() {
        var user = new User ({
            name: 'Test Case 1',
            email: 't1@example.com',
            pass: 'pass',
            img: 'path/to/img.jpg'
        });
        user.save(function(id) {
            id.should.be.ok;
            var uid = id;
        });
    })
    it('should save the user', function() {
        var ret = User.find(uid);
        ret.should.be.ok;
        ret.should.have.property('description');
        ret.name.should.equal('Test Case 1');
        ret.email.should.equal('t1@example.com');
    })
 })

What would be best practices for testing this type of function?

Thanks

score 0 · Answer 1 · answered Apr 17 '16 at 23:10

The actual interaction with the database should not be handled by unit testing but by end to end testing. The best practices for end to end testing with a database are to define a database state which will be loaded into the database before each test.

In terms of unit testing, because this method is a wrapper to call an external module, it's probably enough to defer unit testing to the third party.

Best practice for decoupling queries from testing

1 Answers1