pytestgen-ai 0.1.0

Auto-generate pytest tests for Python functions using Groq AI

pytestgen-ai

Auto-generate pytest tests for Python functions using Groq AI.

What it does

pytestgen-ai reads your Python files, extracts all public functions using AST parsing, sends each function to Groq AI in parallel, and writes a complete test_<filename>.py file with pytest test cases — including a coverage report.

your code → AST parsing → Groq AI (parallel) → test file → coverage report

Installation

pip install pytestgen-ai

Set your Groq API key (get one free at console.groq.com):

export GROQ_API_KEY=your_key_here

Or create a .env file in your project:

GROQ_API_KEY=your_key_here

Usage

Single file:

pytestgen-ai auth.py

Entire folder:

pytestgen-ai --folder src/

Custom output directory:

pytestgen-ai auth.py --output tests/
pytestgen-ai --folder src/ --output tests/

Example

Given auth.py:

def login(username, password):
    if not username or not password:
        raise ValueError("Username and password required")
    if username == "admin" and password == "secret":
        return True
    return False

Running:

pytestgen-ai auth.py

Output:

Processing: auth.py
  Found 2 function(s): ['login', 'is_strong_password']
  Tests written to: test_auth.py
  Running coverage...

  Name      Stmts   Miss  Cover   Missing
  ----------------------------------------
  auth.py      14      0   100%
  ----------------------------------------
  ✅ All tests passed.

Generated test_auth.py:

import pytest
from auth import login

def test_normal_case_login():
    assert login("admin", "secret") == True

def test_empty_username_login():
    with pytest.raises(ValueError):
        login("", "secret")

def test_invalid_credentials_login():
    assert login("user", "wrong") == False

How it works

1. AST parsing — uses Python's built-in ast module to extract every public function and class from your file
2. External call detection — automatically detects DB calls, requests, and other external dependencies that need mocking
3. File type detection — detects if the file uses DB, Selenium, or requests
4. Groq AI (parallel) — sends all functions to Groq simultaneously using async, so large files generate faster
5. Test file — writes a complete test_<filename>.py ready to run with pytest
6. Coverage — automatically runs pytest --cov and displays the report

Supported file types

File type	Support
Pure functions	✅ Full support
Input validation	✅ Full support
Class methods	✅ Supported — class is imported, methods called via instance
Database (psycopg2, SQLAlchemy)	⚠️ Partial — external calls mocked automatically
requests / httpx	⚠️ Partial — external calls mocked automatically
Selenium	❌ Skipped — browser automation not supported

REST API

pytestgen-ai also ships with a FastAPI endpoint. Install with the optional API dependencies:

pip install pytestgen-ai[api]

Then run:

uvicorn api:app --reload

Upload a .py file via POST /generate and get the generated test content back as JSON.

Interactive docs available at http://127.0.0.1:8000/docs.

Tech stack

• Typer — CLI
• Groq API — AI test generation (llama-3.3-70b-versatile)
• Python AST — function extraction and external call detection
• pytest-cov — coverage reports
• FastAPI — REST API

Limitations

• Works best with pure utility functions and business logic
• Algorithm-heavy code (linked lists, trees, monotonic stacks) may have incorrect expected values in assertions — the AI traces complex pointer logic imperfectly
• Duplicate return values across functions in the same file may cause test confusion
• Generated tests should always be reviewed before committing to production
• Requires a Groq API key (free tier available)

License

MIT