Testing React Apps: Beginner's Guide to TDD
Testing is crucial for ensuring React apps are stable and bug-free. Popular tools like Jest and React Testing Library make testing React components simple.
Let’s look at how to write great tests for React:
render Component
Render the component into a test environment using render
from React Testing Library:
This renders the component virtually for testing.
Fire Events
Simulate user events like clicks with fireEvent
:
Assertion Matchers
Use matchers like toBeInTheDocument
to make assertions:
Mock Functions
Spy on callbacks with mock functions:
This allows asserting function calls.
Summary
- Use render to mount components
- Fire events to simulate interaction
- Make assertions with matchers
- Spy on callbacks with mock functions
Automated testing results in robust React components you can refactor with confidence.