Validation

Configure test, lint, and compile commands for change verification.

Validation commands verify that changes work correctly. Nella can run tests, lints, and compile checks after the AI agent makes changes.

Validation Configuration

The validation object accepts three optional commands:

Property	Type	Required	Description
test	string	No	Command to run tests (e.g., npm test)
lint	string	No	Command to run lints (e.g., npm run lint)
compile	string	No	Command to run type checking (e.g., tsc --noEmit)

Basic Configuration

const validation = {
  test: 'npm test',
  lint: 'npm run lint',
  compile: 'tsc --noEmit',
};

Framework Examples

Node.js / npm

const validation = {
  test: 'npm test',
  lint: 'npm run lint',
  compile: 'npm run typecheck',
};

pnpm

const validation = {
  test: 'pnpm test',
  lint: 'pnpm lint',
  compile: 'pnpm typecheck',
};

Yarn

const validation = {
  test: 'yarn test',
  lint: 'yarn lint',
  compile: 'yarn typecheck',
};

Python / pytest

const validation = {
  test: 'pytest',
  lint: 'ruff check .',
  compile: 'mypy .',
};

Go

const validation = {
  test: 'go test ./...',
  lint: 'golangci-lint run',
  compile: 'go build ./...',
};

Rust

const validation = {
  test: 'cargo test',
  lint: 'cargo clippy',
  compile: 'cargo check',
};

Validation Results

Nella returns detailed results for each validation command:

## Validation Results

✅ All validations passed

### Test
- Command: `npm test`
- Status: ✅ Passed
- Duration: 4.2s

### Lint
- Command: `npm run lint`
- Status: ✅ Passed
- Duration: 1.1s

### Compile
- Command: `tsc --noEmit`
- Status: ✅ Passed
- Duration: 2.8s

Failed Validation

When a validation fails, Nella includes the error output:

## Validation Results

❌ 1 of 3 validations failed

### Test
- Command: `npm test`
- Status: ❌ Failed (exit code 1)
- Duration: 3.5s
- Output:
  FAIL src/auth.test.ts
    ✕ should authenticate valid user (15ms)

  Expected: true
  Received: false

### Lint
- Command: `npm run lint`
- Status: ✅ Passed
- Duration: 1.0s

### Compile
- Command: `tsc --noEmit`
- Status: ✅ Passed
- Duration: 2.6s

Advanced Configuration

Targeted Tests

Run only relevant tests instead of the full suite:

// Run tests for specific file
const validation = {
  test: 'npm test -- --testPathPattern=auth',
};

// Run tests with specific tag
const validation = {
  test: 'npm test -- --grep="authentication"',
};

With Coverage

Include coverage reporting:

const validation = {
  test: 'npm test -- --coverage --coverageThreshold=\'{"global":{"branches":80}}\'',
};

Execution Order

Commands are executed in this order:

1. Test
2. Lint
3. Compile

Best Practices

1. Use fast commands — Validation runs after each change, so keep commands fast
2. Be specific — Target relevant tests instead of running everything
3. Fail fast — Configure tests to stop on first failure when possible
4. Include type checking — Catch type errors before they become runtime issues
5. Keep it simple — Complex validation pipelines slow down the development flow

Next Steps

• See Constraints for defining rules
• See Configuration Overview for the full picture