Using Promise.all with assertion - promise

I have a small test (Mocha/Chai), which tests that the encryptPass function returns the correct hash:
const assert = require('chai').assert;
const bcrypt = require('bcrypt');
var encryptPass = require('../../shared/helpers/encryptPass.js');
var createUUID = require('../../shared/helpers/createUUID.js');
describe('encryptPass', function() {
it('returns correct password hash', () => {
var pass = createUUID();
var encryptedPass = encryptPass(pass);
Promise.all([pass, encryptedPass]).then(values => {
let [pass, encryptedPass] = values;
var compareResult = bcrypt.compareSync(pass, encryptedPass);
assert.equal(compareResult, true);
});
});
});
My concern is that there is that the assertion is assuming that the Promise.all function will work without throwing an error. How best to handle this?

Just return the promise that results from your test:
it('returns correct password hash', () => {
var pass = createUUID();
var encryptedPass = encryptPass(pass);
// Just return...
return Promise.all([pass, encryptedPass]).then(values => {
let [pass, encryptedPass] = values;
var compareResult = bcrypt.compareSync(pass, encryptedPass);
assert.equal(compareResult, true);
});
});
This will take care of telling Mocha that your test is asynchronous. In your original code, Mocha won't wait for the test to complete. Returning the promise forces it to wait. Secondly, by returning the promise you also control whether the test will be successful or not. If any of the promises passed to Promise.all is rejected, that's a test failure. If the code in your .then handler fails, that's also a test failure. For instance if assert.equal fails, an AssertionError is raised, which results in a promise rejection, which Mocha treats as a failure.

Related

I tried to maka a QUnit async test for checking ajax update

I tried to maka a QUnit async test for checking ajax update.
I read of QUnit.asyncTest here
https://www.sitepoint.com/test-asynchronous-code-qunit/
but if i try this i get a
TypeError: QUnit.asyncTest is not a function
thats the complete source: https://gist.github.com/232457b002e5363439aece7535600356
of course i new by using QUnit and used JavaScript not for long time.
that a snippet of the part where the error happens:
function max() {
var max = -Infinity;
for (var i = 0; i < arguments.length; i++) {
if (arguments[i] > max) {
max = arguments[i];
}
}
return max;
}
// https://www.sitepoint.com/test-asynchronous-code-qunit/
//TypeError: QUnit.asyncTest is not a function
QUnit.asyncTest('max', function (assert) {
expect(1);
window.setTimeout(function() {
assert.strictEqual(max(3, 1, 2), 3, 'All positive numbers');
QUnit.start();
}, 0);
});
this test gives no syntax error but gives old date:
QUnit.test('usersInnerHTMLlength_Is24', function(assert) {
// problem: this not reads the updates done by ajax. means that are old data:
let innerHTMLlength = $("#users").html().toString().length;
assert.equal(innerHTMLlength, 24);
});
May its not possible to check ajax with QUnit?
I thougt this when i have read here:
QUnit testing AJAX calls
I use it inside a Wordpress Plugin
That sitepoint article is very old (by web standards). You'll need to use the newer syntax found on the documentation website:
function someAsyncThing(value) {
return new Promise(function (resolve, reject) {
setTimeout(function() {
if (value > 5) {
resolve(value);
} else {
reject(new Error("bad value"));
}
}, 500);
});
}
QUnit.test( "some async thing success test", function( assert ) {
// This is what tells QUnit the test is asynchronous
// "done" here will be a callback function used later
var done = assert.async();
// Now call your Async code, passing in a callback...
someAsyncThing(10)
.then(function(result) {
// do your assertions once the async function ends...
assert.equal(result, 10)
// Now tell QUnit you're all done with the test
done();
})
// we can pass the "done" callback from above into catch() to force a test failure
.catch(done);
});
QUnit.test( "some async thing FAILURE test", function( assert ) {
var done = assert.async();
someAsyncThing(4)
.then(function() {
done(new Error("we should NOT succeed with a value < 5"));
})
.catch(function(err) {
assert.equal(err.message, "bad value")
});
});

Execute function if and only if a certain amount of time has elapsed since subscription with RxJS

I am making an API call through an Observable. If this API call takes more than 200ms, I would like to show a loading screen (by assigning 'true' to my 'loading' variable), otherwise I don't want to show anything, in order to avoid a blink on screen.
Is there an RxJS operator capable of doing this ?
this.apiService.get(`/api/someEndpoint`)
// I hope for something like
.triggerIfAtLeastThisAmountOfTimeHasElapsed(200, () => {
this.loading = true;
})
.subscribe(response => {
// Process the response
this.loading = false;
});
There are many ways to do this so you can use for example this:
const api = this.apiService.get(`/api/someEndpoint`);
const loading = Observable
.timer(1000)
.do(() => loading = true) // show loading
.ignoreElements(); // or `filter(() => false)
Observable.merge(api, loading)
.take(1)
.subscribe(() => loading = false);
Along the same lines of Martin's response, this is an example that should simulate your context
const obs1 = Observable.timer(200).take(1);
const apiSubject = new Subject<string>();
const apiObs = apiSubject.asObservable();
const apiExecutionElapsed = 1000;
const obs3 = Observable.merge(obs1, apiObs);
let loading = undefined;
obs3.subscribe(
data => {
console.log(data);
if (loading === undefined && data === 0) {
loading = true;
} else {
loading = false;
}
console.log('loading', loading);
},
console.error,
() => {
loading = false;
console.log('loading', loading);
}
)
setTimeout(() => {
apiSubject.next('I am the result of the API');
apiSubject.complete()}, apiExecutionElapsed)
If the execution of the api (apiExecutionElapsed) takes longer than the configured timer (200 ms in this case) you see the loading flag to become first true and then false. Otherwise it remains always false.

Jasmine - Multiple it's, one asynchronous call

Scenario
I'm trying to do multiple it specs on a single external load rather than have the external data loaded EVERY time.
Question
How can I do this with a single call of getExternalValue while still keeping my it definitions?
Ideas
Currently I'm doing all the expects in a single it block. I've also thought about storing the loaded value before my tests but then I'd have to find another way to make jasmine wait until the value is loaded.
Code
function getExternalValue(callback) {
console.log("getting external value");
setTimeout(function() {
callback(true);
}, 2000);
return false;
}
describe("mjaTestLambda()", function() {
it("is truthy", function(done) {
let truthy;
truthy = getExternalValue(function(bool) {
truthy = bool;
expect(truthy).toBeTruthy();
done();
});
});
it("is falsy", function(done) {
let truthy;
truthy = getExternalValue(function(bool) {
truthy = bool;
expect(!truthy).toBeFalsy();
done();
});
});
});
How can I do this with a single call of getExternalValue while still
keeping my it definitions?
Use beforeEach() or beforeAll() to get the resolved value. Personally I suggest beforeEach() as it will reset the value for each test and helps ensure a clean setup for each one.
I noticed your function has a callback parameter. Async/await is a useful pattern that works best when (1) you're writing async/await functions or (2) your functions return a Promise. If you need to keep the callback parameter, let me know and I'll update the following:
// returns Promise
function getExternalValue() {
return new Promise((resolve, reject) => {
console.log("getting external value");
setTimeout(() => {
resolve(true);
}, 2000);
});
}
describe("mjaTestLambda()", () => {
let value;
beforeAll(() => {
return getExternalValue()
.then((v) => { value = v; });
});
it("is truthy", () => {
expect(v).toBeTruthy();
});
it("is not falsy", () => {
expect(!v).toBeFalsy();
});
});

Jasmine spyOn function call inside function under test

I am trying to use Jasmine to test the following function:
var Pdba = Class.create();
Pdba.prototype = {
getChangeGroup: function(userId) {
var query = 'active=true^u_change_group=true^u_organization=false^';
var exGroup = new CompanyGroup();
var groups = exGroup.getGroupsByQuery(userId, query); //want to spy/mock this call
if (groups.next()) {
return groups.sys_id.toString();
}
return '';
}
type: 'Pdba'
};
I want to SpyOn the getGroupsByQuery() call, so that it doesn't make the actual call. Below is a collection of various things I have been trying, mostly just to see if I can "spy" and see that it has been called, then work on overriding so that I can replace the call with my own data.
describe('my suite of getChangeGroup tests', function() {
var expPdba;
var validUserId = 'user1';
var expGrp;
var ggbqMoc
beforeEach(function() {
expPdba = new global.Pdba();
coGrp = new CompanyGroup();
spyOn(coGrp, 'getGroupsByQuery');
ggbqMoc = jasmine.createSpy('getGroupsByQuery');
});
it('should return \'\' for empty userId', function() {
coPdba.getChangeGroup('');
expect(coGrp.getGroupsByQuery).toHaveBeenCalled();
expect(ggbqMoc).toHaveBeenCalled();
});
});
Is this possible or do I need to change the function under test to take a 'CompanyGroup' as a parameter?
Thank you
I'm assuming you are using jasmine v3. The syntax for creating a spy is pretty weird now- you have to pass a string that refers to the name of the variable you want to create a spy for, and then you pass an array of function names that should be spied on.
Try this:
describe('my suite of getChangeGroup tests', function() {
var expPdba;
var validUserId = 'user1';
var expGrp;
var spy;
beforeEach(function() {
expPdba = new global.Pdba();
coGrp = new CompanyGroup();
spy = jasmine.createSpyObj('coGrp', ['getGroupsByQuery'])
});
it('should return \'\' for empty userId', function() {
coPdba.getChangeGroup('');
expect(coGrp.getGroupsByQuery).toHaveBeenCalled();
expect(spy).toHaveBeenCalled();
});
});

Nativescript - Pass array from home-view-model to home.js

I´m having a hard time understanding how to perform this action(as the title says), and maybe someone could help me understand the process, my code is below:
My home-view-model:
var Observable = require("data/observable").Observable;
var ObservableArray = require("data/observable-array").ObservableArray;
var http = require("http");
function createViewModel() {
http.getJSON("http://myJsonfile").then(function (r) {
var arrNoticias = new ObservableArray(r.data);
return arrNoticias;
}, function (e) {
});
}
exports.createViewModel = createViewModel;
I have done a console.log of the arrNoticias before i have putted it inside a callback function and it returns [object object] etc...and then i have done this:
console.log(arrNoticias.getItem(0).titulo);
and it returns the info i need!.
Then in my home.js file i have this:
var observableModule = require("data/observable")
var ObservableArray = require("data/observable-array").ObservableArray;
var arrNoticias = require('./home-view-model.js');
console.log(arrNoticias.getItem(0).titulo);
and the result in the console is:
TypeError: arrNoticias.getItem is not a function. (In 'arrNoticias.getItem(0)', 'arrNoticias.getItem' is undefined)
My question is, how does this action is perform? passing the data from view-model to the .js file?
Thanks for your time
Regards
As that function send a URL request so probably it's an async function, which is on hold while requesting so that's why you get undefined. Normally, you will want your function that sends a URL request to return a promise. Based on that promise, you will the result as expected after the request is done. So:
function createViewModel() {
return new Promise<>((resolve, reject) => {
http.getJSON("http://myJsonfile").then(function (r) {
var arrNoticias = new ObservableArray(r.data);
resolve(arrNoticias);
}, function(e) {
reject(e);
});
}), (e) => {
console.log(e);
})
}
In home.js:
var homeVM= require('./home-view-model.js');
var arrNoticias;
homeVM.createViewModel().then(function(r) {
arrNoticias = r;
});

Resources