What is "Testing Reducers vs. Testing Components" about?

UI tests break when the DOM changes, even when logic is correct. A pure reducer is a plain function -- test it by calling it with inputs and asserting outputs. No render, no selectors needed.

What topics does "Testing Reducers vs. Testing Components" cover?

This article covers: testing react reducer, unit testing react, pure function testing, reducer test vitest, react application logic test, test business logic react.

Testing Reducers vs. Testing Components

Testing UI components is brittle — the test breaks every time the markup changes even when the logic is fine. Pull the logic into pure reducers and test those directly. The tests stay stable, and the coverage that matters actually holds.

June 7, 20261 min read4 / 4

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