test-generator

# test-generator

Generate comprehensive, idiomatic tests for any function, class, module, or API endpoint. test-generator understands your code's intent and produces tests that cover happy paths, edge cases, error conditions, and boundary values — across every major testing framework.

## What It Does

test-generator performs deep code analysis to produce tests that actually matter:

- **Coverage-driven generation**: Analyzes branches, conditions, and return paths to maximize coverage
- **Edge case discovery**: Integer overflows, null/undefined inputs, empty collections, maximum length strings, concurrent access patterns
- **Mock generation**: Auto-generates mocks for external dependencies, HTTP clients, databases, and file system calls
- **Fixture creation**: Generates realistic test data and factory functions based on type signatures
- **Assertion quality**: Uses framework-idiomatic matchers (toBe, assertEqual, assert_eq) with meaningful failure messages
- **Test naming**: Descriptive test names following the "should X when Y" convention
- **Framework detection**: Auto-detects the testing framework in use from package.json, pyproject.toml, Cargo.toml, or go.mod

## Installation

```bash
anvil skill install test-generator
```

## Usage

### Generate Tests for a File
```
/test-generator ./src/auth/jwt.ts
```

### Generate Tests for a Specific Function
```
/test-generator ./src/utils/parser.ts --function parseUserInput
```

### Generate Integration Tests
```
/test-generator ./src/routes/users.ts --type integration
```

### Generate E2E Tests with Playwright
```
/test-generator ./src/pages/Login.tsx --type e2e --framework playwright
```

### Generate Tests with Specific Coverage Target
```
/test-generator ./src/lib/ --coverage 90
```

### Generate for a Python Module
```
/test-generator app/services/auth.py --framework pytest
```

## Supported Frameworks

| Language | Frameworks |
|----------|------------|
| JavaScript/TypeScript | Jest, Vitest, Mocha, Jasmine |
| Python | Pytest, unittest, nose2 |
| Go | testing, testify, ginkgo |
| Rust | cargo test, rstest, proptest |
| E2E | Playwright, Cypress, Selenium |

## Configuration Options

| Option | Description | Default |
|--------|-------------|---------|
| `--type` | unit, integration, e2e | unit |
| `--framework` | Override auto-detected framework | auto |
| `--coverage` | Target coverage percentage | 80 |
| `--mocks` | Mock strategy: auto, manual, none | auto |
| `--output` | Output file path | <file>.test.ts |
| `--watch` | Watch mode: re-generate on source change | false |

## Requirements

- Source file or directory to generate tests for
- Compatible test framework installed in the project