Test Generator

Test Generator

When to use this skill

Activate when the user wants to:

• Create test files for existing source code
• Scaffold test stubs with correct imports and structure
• Add test coverage to an untested module

Instructions

1. Analyze the source file to extract function and class signatures:

   deno run --allow-read scripts/analyze-source.ts <source-file>
   

2. Review the JSON output to understand the public API
3. Generate test stubs:

   deno run --allow-read --allow-write scripts/generate-stubs.ts <source-file> --output <test-file> --framework vitest
   

   Supported frameworks: vitest (default), jest, mocha
4. Fill in the generated test bodies with meaningful assertions
5. Run the tests to verify the stubs compile and the structure is correct

Output format

The analysis script outputs:

{
  "file": "utils.ts",
  "functions": [
    { "name": "formatDate", "params": ["date: Date", "locale?: string"], "returnType": "string", "async": false, "exported": true }
  ],
  "classes": [
    { "name": "UserService", "methods": ["getById", "create", "delete"], "exported": true }
  ]
}

Gotchas

• Deno 2.0+ is required — these scripts do not run under Node.js
• Analysis uses regex-based parsing, not a full TypeScript compiler — some edge cases may be missed
• Generated tests are stubs with placeholder assertions (expect(...).toBeDefined()) — fill in real logic
• For framework-specific patterns (mocking, setup/teardown), read references/TESTING-PATTERNS.md