sinon-stub-superagent-promise
v0.0.12
Published
Superagent Bluebird Promise stubbing for Sinon.JS
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sinon-stub-superagent-bluebird-promise V 0.0.11
This package was inspired by sinon-stub-promise in order to test superagent-bluebird-promise. That makes testing of promises easier when stubbing with Sinon.JS. This library ensures stubbed promises are evaluated synchronously, so that no special async tricks are required for testing.
Installation
Install with npm: npm install --save-dev sinon-stub-superagent-bluebird-promise
In node, you can initialize with sinon:
var sinon = require('sinon');
var sinonStubPromise = require('sinon-stub-superagent-bluebird-promise');
sinonStubSuperagentBluebirdPromise(sinon);
Or in the browser, you can just include
node_modules/sinon-stub-superagent-bluebird-promise/index.js
(assumes sinon is available on
window object).
Example
// Code under test
function getValuesByParams(params) {
var request = require('superagent-bluebird-promise');
return request
.get('http://someurl.com/?params=' + params)
.set({'accept': 'application/vnd.someApp.v2+json'})
.then(doSomething)
.catch((e) => {
console.error(e);
});
}
// Test
var sinon = require('sinon');
var sinonStubSuperAgentPromise = require('sinon-stub-superagent-bluebird-promise');
describe('stubbing a superagent promise', function() {
var getStub;
beforeEach(function() {
getStub = sinon.stub().returnsPromise();
getStub.resolves({ body: someData });
serviceWeWantToTest = proxyquire('../app/services/someService.js', {
'superagent-bluebird-promise': {
get: getStub
}
});
});
it('can resolve', function() {
promise.resolves('resolve value')
var testObject = {};
doSomethingWithAPromise(promise, testObject);
expect(testObject.resolved).to.eql('resolve value');
});
it('can reject', function() {
promise.rejects('reject value')
var testObject = {};
doSomethingWithAPromise(promise, testObject);
expect(testObject.rejected).to.eql('reject value');
});
}
Why?
I've look around and could only find the sinon-stub-promise and start changing it so I realize I should create a new package.
[sinon-as-promised](https://www.npmjs.com/package/sinon-as-promised), uses a
promise under the hood to achieve the stubbing. The issue with this, is that
the promise is evaluated asynchronously, so the test code has to deal with that
by delaying the assertion until the promise has a chance to run.
Additionally, sinon-as-promised requires you to call either `stub.resolves()`
or `stub.rejects()` before it will setup the stub as a "thenable" object (one
that has `then` and `catch` on it). The trouble with this is that if you are
testing conditional branches (e.g. test what happens when promise succeeds,
then test what happens when promise fails), you have to either resolve or
reject the promise for the code under test to pass.
Stability?
This is not a [Promises/A+](https://promisesaplus.com/) compliant library. We
built it to support how we are currently using promises. There is a test suite
that will grow over time as we identify any short comings of this library.