Chai is a BDD/TDD assertion library for Node.js and browsers that can be used with any Javascript testing framework.
Chai is a bdd/tdd assertion library for node.js and browser that can be used with any javascript testing framework.
Questions tagged [chai]
2953 questions
336
votes
7 answers
Mocha / Chai expect.to.throw not catching thrown errors
I'm having issues getting Chai's expect.to.throw to work in a test for my node.js app. The test keeps failing on the thrown error, but If I wrap the test case in try and catch and assert on the caught error, it works.
Does expect.to.throw not work…
doremi
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277
votes
7 answers
chai test array equality doesn't work as expected
Why does the following fail?
expect([0,0]).to.equal([0,0]);
and what is the right way to test that?
kannix
- 5,107
- 6
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237
votes
7 answers
In mocha testing while calling asynchronous function how to avoid the timeout Error: timeout of 2000ms exceeded
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…
sachin
- 13,605
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202
votes
3 answers
What is the difference between “assert”, “expect”, and “should” in Chai?
What is the difference between assert, expect, and should? When to use what?
assert.equal(3, '3', '== coerces values to strings');
var foo = 'bar';
expect(foo).to.equal('bar');
foo.should.equal('bar');
Manu
- 3,979
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172
votes
4 answers
How do I properly test promises with mocha and chai?
The following test is behaving oddly:
it('Should return the exchange rates for btc_ltc', function(done) {
var pair = 'btc_ltc';
shapeshift.getRate(pair)
.then(function(data){
expect(data.pair).to.equal(pair);
…
chovy
- 72,281
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169
votes
8 answers
Getting a UnhandledPromiseRejectionWarning when testing using mocha/chai
So, I'm testing a component that relies on an event-emitter. To do so I came up with a solution using Promises with Mocha+Chai:
it('should transition with the correct event', (done) => {
const cFSM = new CharacterFSM({}, emitter, transitions);
…
Jzop
- 1,735
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135
votes
3 answers
When should you use render and shallow in Enzyme / React tests?
prior to posting this question, I tried to search in sqa stackexchange but I found no post about shallow and render there, so I hope someone can help me out here.
When should I use shallow and render in testing react components?
Based on the airbnb…
Cyval
- 2,429
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135
votes
10 answers
Mocha API Testing: getting 'TypeError: app.address is not a function'
My Issue
I've coded a very simple CRUD API and I've started recently coding also some tests using chai and chai-http but I'm having an issue when running my tests with $ mocha.
When I run the tests I get the following error on the shell:
TypeError:…
charliebrownie
- 5,777
- 10
- 35
- 55
108
votes
3 answers
Testing for errors thrown in Mocha
I'm hoping to find some help with this problem. I'm trying to write tests for an application I am writing. I have distilled the problem in to the following sample code. I want to test that an error was thrown. I'm using Testacular as a test…
Chris Neitzer
- 1,183
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- 7
105
votes
9 answers
Chai: how to test for undefined with 'should' syntax
Building on this tutorial testing an angularjs app with chai, I want to add a test for an undefined value using the "should" style. This fails:
it ('cannot play outside the board', function() {
scope.play(10).should.be.undefined;
});
with error…
thebenedict
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90
votes
6 answers
Nice way to get rid of no-unused-expressions linter error with chai
In my Chai tests I often find myself wanting to use their assertions that are something like .to.be.empty, .to.be.true e.t.c., because I find them to be cleaner to read than .to.be.length(1) or .to.be.equal(true). However, this breaks my linter (I'm…
Ben Hare
- 4,365
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84
votes
1 answer
Mocha not exiting after test
I'm starting with tests in Node. Using mocha, chai and nock (to intercept external HTTP api calls).
I have written 3 tests, all of them are a pass, however, when I added the 3rd test, mocha stopped exiting after running the tests, with no error or…
Fede E.
- 2,118
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82
votes
3 answers
How to unit test a method of react component?
I am trying to unit test my reactjs component:
import React from 'react';
import Modal from 'react-modal';
import store from '../../../store'
import lodash from 'lodash'
export class AddToOrder extends React.Component {
constructor(props)…
bier hier
- 20,970
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81
votes
15 answers
Verify that an exception is thrown using Mocha / Chai and async/await
I'm struggling to work out the best way to verify that a promise is rejected in a Mocha test while using async/await.
Here's an example that works, but I dislike that should.be.rejectedWith returns a promise that needs to be returned from the test…
plexer
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78
votes
9 answers
How can I check that two objects have the same set of property names?
I am using node, mocha, and chai for my application. I want to test that my returned results data property is the same "type of object" as one of my model objects (Very similar to chai's instance). I just want to confirm that the two objects have…
dan27
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