Unit testing Javascript applications with qunit and sinon
Training goals
- Introduction to the tools (QUnit, Sinon)
- Overview of the test runner (Karma)
- How we integrate testing into a build
Qunit
TDD style testing framework that groups tests into modules and uses assertions to pass/fail tests.
QUnit running in the browser.
Assertion Types
| Truthiness | |
assert.ok(value)
|
Boolean(value) === true
|
assert.notOk(value)
|
Boolean(value) === false
|
| Equality | |
assert.equal(value1, value2)
|
value1 == value2
|
assert.strictEqual(value1, value2)
|
value1 === value2
|
assert.notEqual(value1, value2)
|
value1 != value2
|
assert.notStrictEqual(value1, value2)
|
value1 !== value2
|
assert.deepEqual(value1, value2)
|
angular.equals(value1, value2)*
|
Assertion Types (continued)
| Equality | |
assert.notDeepEqual(value1, value2)
|
!angular.equals(value1, value2)*
|
| Exceptions | |
assert.throws(func, Error)
|
function func() { throw new Error; }
|
sinon.js
Test spies, stubs, and additional assertions for dependencies used within your test.
sinon spies
- When you want to inspect the inputs and return values of a function.
- Validating your call stack
- Keep them within the object / class under test
sinon stubs
- When you want to inspect the inputs and return values of a function with predetermined behaviors.
- Use for calls out to dependencies
- Resources
- Services
- Really anything that is not the object / class under test.
sinon matchers
- Indicate a level of specificity for matching values
- Fuzzy or strict matching
- Good for matching objects
- Good for matching types like Array, RegExp, and Object
- Good for testing truthy / falsy values
Karma
A pluggable, framework-agnostic test runner with support for multiple browsers and devices.
Karma monitoring multiple browsers.
final thoughts
- Writing good tests is like writing good code - it takes practice and patterns
- 100% coverage is NOT the goal
- Stability is the goal
- Tests help to define your interface
Questions?
Unit Testing JavaScript Applications with QUnit and Sinon
By Eric Adams
Unit Testing JavaScript Applications with QUnit and Sinon
Intro to the tools used and why they're used.
