npm install --save-dev @testing-library/angular
yarn add --dev @testing-library/angular
You want to write maintainable tests for your Angular components. As a part of this goal, you want your tests to avoid including implementation details of your components and rather focus on making your tests give you the confidence for which they are intended. As part of this, you want your testbase to be maintainable in the long run so refactors of your components (changes to implementation but not functionality) don't break your tests and slow you and your team down.
Angular Testing Library is a very lightweight solution for testing Angular
components. It provides light utility functions on top of
DOM Testing Library
in a way that encourages better testing practices. Its primary guiding principle
So rather than dealing with instances of rendered Angular components, your tests
will work with actual DOM nodes. The utilities this library provides facilitate
querying the DOM in the same way the user would. Finding form elements by their
label text (just like a user would), finding links and buttons from their text
(like a user would). It also exposes a recommended way to find elements by a
data-testid as an "escape hatch" for elements where the text content and label
do not make sense or is not practical.
This library encourages your applications to be more accessible and allows you to get your tests closer to using your components the way a user will, which allows your tests to give you more confidence that your application will work when a real user uses it.
Angular Testing Library:
- Re-exports the
fireEventutility functions from
DOM Testing Library.
- Encapsulates the
fireEventfunctions of your component to automatically call
detectChanges()after an event occurs
- Is test framework agnostic, it runs on every test framework