Stubs are functions/programs that simulate the behaviors of components/modules. Stubs provide canned answers to function calls made during test cases.
An example can be writing a file, without actually doing so.
var fs = require('fs')
var writeFileStub = sinon.stub(fs, 'writeFile', function (path, data, cb) {
return cb(null)
})
expect(writeFileStub).to.be.called
writeFileStub.restore()
