Implementation:Cypress io Cypress Vitest Config

Knowledge Sources	Cypress
Domains	Testing, Development
Last Updated	2026-02-12 00:00 GMT

Overview

Concrete Vitest configuration for running unit tests across the Cypress monorepo with per-package configs aggregated at the root level.

Description

The root vitest.config.ts (L1-17) uses Vitest's workspace feature to aggregate all per-package configurations. It defines test.projects pointing to all package-level vitest configs ({packages,tooling,scripts}/*/vitest.config.{ts,mjs}). V8 coverage provider generates clover-format reports.

Usage

Run vitest from the repository root for the full test suite, or from a specific package directory for package-level tests.

Code Reference

Source Location

• Repository: cypress-io/cypress
• File: vitest.config.ts
• Lines: L1-17

Signature

import { defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    projects: [
      '{packages,tooling,scripts}/*/vitest.config.{ts,mjs}',
      'cli/vitest.config.*',
    ],
    coverage: {
      provider: 'v8',
      reporter: ['clover'],
    },
    reporters: ['default', 'junit'],
  },
})

Import

# Run all tests
npx vitest

# Run with coverage
npx vitest --coverage

# Run specific package tests
npx vitest --project @packages/config

I/O Contract

Inputs

Name	Type	Required	Description
Test files	*.spec.ts	Yes	Test specification files across packages
Per-package configs	vitest.config.ts	Yes	Package-level Vitest configurations

Outputs

Name	Type	Description
Test results	stdout	Pass/fail counts per package
JUnit XML	file	JUnit report for CI integration
Coverage report	clover XML	V8 code coverage in clover format

Usage Examples

Running Tests

# Run full test suite
npx vitest

# Run in watch mode during development
npx vitest --watch

# Run with coverage
npx vitest --coverage

# Run specific package
cd packages/config && npx vitest

Related Pages

Implements Principle

• Principle:Cypress_io_Cypress_Test_Suite_Execution