Suggest an editImprove this articleRefine the answer for “What is component testing?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**Component testing** is checking individual UI components in isolation to make sure they render correctly, handle data and respond to user actions. **Key point:** this approach lets you find errors at the earliest level, before the component is integrated into larger screens and scenarios.Shown above the full answer for quick recall.Answer (EN)ImageComponent testing is checking **individual UI components in isolation** to make sure they render correctly, handle data and respond to user actions. This approach lets you find errors at the earliest level, before the component is integrated into larger screens and scenarios. --- ### **The task of component testing** Guarantee that a specific component: - renders with the correct content - correctly changes state on actions (click, input, etc.) - correctly displays different input data (props, state) - calls the right functions or events --- ### **What is usually checked** - correct text, markup and elements in the DOM - reactions to user actions - state changes - correct output for different props - correct rendering in different states (loading, error, empty, success) --- ### **Where it is used** - React - Vue - Angular - Any modern UI frameworks --- ### **Summary** Component testing provides **reliability and predictability of the UI at the level of the interface's building blocks**, before these blocks are assembled into full user scenarios.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.