Regression Test

General

// Definition

A test that verifies previously fixed bugs haven't returned and existing features still work after new changes. Forms the safety net for refactoring and feature work.

// Code Example

CypressPin a fixed bug with a regression test

TypeScript

// Bug #1234 — empty cart crashed the checkout page
it('handles an empty cart gracefully', () => {
  cy.visit('/checkout');
  cy.contains('Your cart is empty').should('be.visible');
  cy.get('[data-testid=continue]').should('be.disabled');
});

// Related terms

Smoke Test
A small, fast test suite that verifies the most critical functionality works after a build — ensures the app is healthy enough for further testing. The first signal in any pipeline.
Retesting
Re-running a test that previously failed, after a fix has been applied, to confirm the original defect is resolved. Distinct from regression testing, which checks unrelated areas.
Test Suite
A collection of related test cases organised for execution together — usually grouped by feature, layer (unit, integration, e2e), or test type (smoke, regression).

Learn more · Software Testing Fundamentals

Chapter 3 · Lesson 2: Smoke, Sanity, and Regression Testing