I'm getting started with mocha testing framework with NodeJS. Success assertions working fine but if the assertion fails, my test timeouts. For asserting I've tried Should and Expect. For example (async code)
it('should create new user', function(done){
userService.create(user).then(function(model){
expect(model.id).to.be(1); //created user ID
done();
}, done)
});
Here the if model id is not 1 then the test timesout instead of reporting failed assertion. I'm sure I'm doing something wrong. Appreciate your help. Thanks!
Shawn's answer works, but there is a simpler way.
If you return the Promise from your test, Mocha will handle everything for you:
it('should create new user', function() {
return userService.create(user).then(function(model){
expect(model.id).to.be(1); //created user ID
});
});
No done callback needed!
expect is throwing an error that is being caught by the promise. Adding a catch condition that calls done fixes this.
it('should create new user', function(done) {
userService.create(user).then(function(model) {
expect(model.id).to.be(1); //created user ID
done();
}).catch(function(e) {
done(e);
})
});
Looks like done is never called. Besides then, you may also need an else to handle the failure.
Related
So I've tried looking up this bug, but I can't seem to find an answer that caters to my bug. I'm using mocha and chai-http to test some API's. I'm just hitting the endpoints using their corresponding RESTFUL methods (POST, GET, PUT) and checking the response (really straight forward). The problem is, individually my test suites work (if I were to run them one at a time), but when I run them using my gulp command ... I get "callback not a function" for some of the test cases (the ones in the if hook if you're familiar with mocha)
Here's the error I'm getting:
Uncaught TypeError: callback.apply is not a function
at Immediate.<anonymous> (node_modules/mongoose/lib/model.js:3683:16)
at Immediate._onImmediate (node_modules/mongoose/node_modules/mquery/lib/utils.js:137:16)
Here's the structure of my directory that my test cases reside:
test
backend
assignments_tests.js
application_tests.js
courses_test.js
& I have a gulp file with the following:
// Set the environment variable for the test cases to point to production
gulp.task('set-testing-env', function() {
return process.env.NODE_ENV = 'production';
})
// gulp task for backend
gulp.task('test-backend', ['set-testing-env'], function() {
return gulp.src('test/backend/**/*.js', {read: false})
.pipe(mocha({
reporter: 'spec',
timeout: 60000
}))
.on('error', function(err) {
// console.log(err);
process.exit();
});
});
& finally a sample of my test case:
describe("testing GET" ....
before(function(done) {
... setting up stuff here and calling done ...
})
describe("get courses information and courses offered", function() {
it("gets a courses information", function(done) {
const endpoint = test.endpoint + "/courseInfo/" + test.course
chai.request(app)
.get(endpoint)
.end(function(err, res) {
expect(err, "Error hitting endpoint").to.be.null;
expect(res, "Expected data in json format").to.be.json;
expect(res, "Expected status to be 200").to.have.status(200);
expect(res.body, "Expected course info!").to.have.length(1);
expect(res.body[0],"Missing keys").to.have.all.keys(courseInfo);
done();
})
})
})
describe("testing POST" ...
before(function(done) {
... setting up and calling done ...
})
describe(...
it(...)
})
})
I'm not too sure why I'm getting a callback not a function error. :(
Any help would be much appreciated!
Probably in some part of code that you didn't include here you are calling a Mongoose method passing something like too many objects as parameters, like in this question:
Async.each throwing error
One of those objects gets interpreted as a function but cannot be called as such.
This is a common problem but you didn;t include any code that runs Mongoose methods so it's hard to tell if that is the issue here.
I'm writing test cases with mocha in Nodejs and want to reset database data before running the tests. I'm using Knex as query builder for executing queries.
I wrote following logic:
describe('Activities:', function() {
before(funtion(){
activityDBOperations.deleteAll()
.then(function(){
// all records are deleted
});
});
it('it should add a record into Activities table: multiple time activity', function(done) {
activityDBOperations.addRecord(requestParams)
.then(function(data) {
expect(data.length > 0).to.equal(true);
done();
});
});
});
The problem is that test cases start executing and not waiting for deleteAll operation to finish. What I understand is since deleteAll is returning promise, the program execution move forward because of asynchronous nature of promises.
How can I make sure that test cases should run only when deleteAll has finished?
Either provide a callback to your before hook and call it in then:
before(function(done) {
activityDBOperations.deleteAll()
.then(function() {
// all records are deleted
done();
});
});
or, according to Mocha docs, just return a promise from before:
before(function() {
return activityDBOperations.deleteAll();
});
Add return statements so the Promises are actually returned.
I am writing many test cases. In all of them there is a common part (signing in the user and doing some other stuff).
So instead of writing that part in every test, I want a function to call it.
I have tried using .then and .call but it throws error:
.setValue('#signin_email', LogInEmail)
^
SyntaxError: Unexpected token .
How is this thing done?
Do you mean this? http://webdriver.io/guide/usage/customcommands.html
browser.addCommand("LogInEmail", function () {
return browser
.setValue('#signin_email', 'emailaddress')
.setValue('#password', 'password');
});
// to invoke
browser.LogInEmail()
If you want to run your common part before every mocha test then put it in beforeEach() function like this.
describe('some test', function() {
beforeEach(function() {
// your common part here
});
it('it should do something, function() {
...
});
...
it('it should do something else', function() {
...
});
});
When testing async code with Mocha and one of my asserts fails, all Mocha does is to report a timeout error. Is there a way to improve this? How to know what asserts failed and why?
mocha
Contact
#getContacts()
1) should return at least 1 contact
0 passing (3s)
1 failing
1) Contact #getContacts() should return at least 1 contact:
Error: timeout of 3000ms exceeded. Ensure the done() callback is being called in this test.
Code:
var assert = require("assert");
var contact = require("../lib/contact.js");
var chai = require('chai');
var should = chai.should();
describe('Contact', function() {
describe('#getContacts()', function() {
it('should return at least 1 contact', function(done) {
contact.getContacts().then(function(contacts) {
assert.equal(4,2)
done()
});
})
})
});
The issue is that the assertion fails, which throws an exception. This causes the promise to be rejected, but there isn't anyone to notice. Your code only checks if the promise succeeds. If you return the promise, then mocha will check for it and fail the test if the promise is rejected.
So you want
it('should return at least 1 contact', function() {
return contact.getContacts().then(function(contacts) {
assert.equal(4,2);
});
});
You should return the promise like this:
it('should return at least 1 contact', function() {
return contact.getContacts().then(function(contacts) {
assert.equal(4,2);
});
});
It seems like when the assert throws an error that error is swallowed and never shown and also the code after assert throws is skipped.
Try like this (catching the reject):
it('should return at least 1 contact', function(done) {
contact.getContacts().then(function(contacts) {
assert.equal(4,2)
done()
}).then(null, function (err) {
console.error(err);
done(err);
});
})
Or instead of then(null, rejectFunc) use catch(rejectFunc) with libs like bluebird.
Also the answer by idbehold is great. I didn't know yet that mocha supports promises directly and I always use the done param knowing if I have a timeout without a stack trace there was a swallowed error in this test.
In my node application I'm using mocha to test my code. While calling many asynchronous functions using mocha, I'm getting timeout error (Error: timeout of 2000ms exceeded.). How can I resolve this?
var module = require('../lib/myModule');
var should = require('chai').should();
describe('Testing Module', function() {
it('Save Data', function(done) {
this.timeout(15000);
var data = {
a: 'aa',
b: 'bb'
};
module.save(data, function(err, res) {
should.not.exist(err);
done();
});
});
it('Get Data By Id', function(done) {
var id = "28ca9";
module.get(id, function(err, res) {
console.log(res);
should.not.exist(err);
done();
});
});
});
You can either set the timeout when running your test:
mocha --timeout 15000
Or you can set the timeout for each suite or each test programmatically:
describe('...', function(){
this.timeout(15000);
it('...', function(done){
this.timeout(15000);
setTimeout(done, 15000);
});
});
For more info see the docs.
I find that the "solution" of just increasing the timeouts obscures what's really going on here, which is either
Your code and/or network calls are way too slow (should be sub 100 ms for a good user experience)
The assertions (tests) are failing and something is swallowing the errors before Mocha is able to act on them.
You usually encounter #2 when Mocha doesn't receive assertion errors from a callback. This is caused by some other code swallowing the exception further up the stack. The right way of dealing with this is to fix the code and not swallow the error.
When external code swallows your errors
In case it's a library function that you are unable to modify, you need to catch the assertion error and pass it onto Mocha yourself. You do this by wrapping your assertion callback in a try/catch block and pass any exceptions to the done handler.
it('should not fail', function (done) { // Pass reference here!
i_swallow_errors(function (err, result) {
try { // boilerplate to be able to get the assert failures
assert.ok(true);
assert.equal(result, 'bar');
done();
} catch (error) {
done(error);
}
});
});
This boilerplate can of course be extracted into some utility function to make the test a little more pleasing to the eye:
it('should not fail', function (done) { // Pass reference here!
i_swallow_errors(handleError(done, function (err, result) {
assert.equal(result, 'bar');
}));
});
// reusable boilerplate to be able to get the assert failures
function handleError(done, fn) {
try {
fn();
done();
} catch (error) {
done(error);
}
}
Speeding up network tests
Other than that I suggest you pick up the advice on starting to use test stubs for network calls to make tests pass without having to rely on a functioning network. Using Mocha, Chai and Sinon the tests might look something like this
describe('api tests normally involving network calls', function() {
beforeEach: function () {
this.xhr = sinon.useFakeXMLHttpRequest();
var requests = this.requests = [];
this.xhr.onCreate = function (xhr) {
requests.push(xhr);
};
},
afterEach: function () {
this.xhr.restore();
}
it("should fetch comments from server", function () {
var callback = sinon.spy();
myLib.getCommentsFor("/some/article", callback);
assertEquals(1, this.requests.length);
this.requests[0].respond(200, { "Content-Type": "application/json" },
'[{ "id": 12, "comment": "Hey there" }]');
expect(callback.calledWith([{ id: 12, comment: "Hey there" }])).to.be.true;
});
});
See Sinon's nise docs for more info.
If you are using arrow functions:
it('should do something', async () => {
// do your testing
}).timeout(15000)
A little late but someone can use this in future...You can increase your test timeout by updating scripts in your package.json with the following:
"scripts": {
"test": "test --timeout 10000" //Adjust to a value you need
}
Run your tests using the command test
For me the problem was actually the describe function,
which when provided an arrow function, causes mocha to miss the
timeout, and behave not consistently. (Using ES6)
since no promise was rejected I was getting this error all the time for different tests that were failing inside the describe block
so this how it looks when not working properly:
describe('test', () => {
assert(...)
})
and this works using the anonymous function
describe('test', function() {
assert(...)
})
Hope it helps someone, my configuration for the above:
(nodejs: 8.4.0, npm: 5.3.0, mocha: 3.3.0)
My issue was not sending the response back, so it was hanging. If you are using express make sure that res.send(data), res.json(data) or whatever the api method you wanna use is executed for the route you are testing.
Make sure to resolve/reject the promises used in the test cases, be it spies or stubs make sure they resolve/reject.