Test-driven development skill for writing unit tests, generating test fixtures and mocks, analyzing coverage gaps, and guiding red-green-refactor workflows across Jest, Pytest, JUnit, Vitest, and Mocha. Use when the user asks to write tests, improve test coverage, practice TDD, generate mocks or stubs, or mentions testing frameworks like Jest, pytest, or JUnit. Handles test generation from source code, coverage report parsing (LCOV/JSON/XML), quality scoring, and framework conversion for TypeScript, JavaScript, Python, and Java projects.
Test-driven development skill for generating tests, analyzing coverage, and guiding red-green-refactor workflows across Jest, Pytest, JUnit, and Vitest.
test_generator.py with requirementsnpm test -- --coverage)coverage_analyzer.py on LCOV/JSON/XML reporttdd_workflow.py --phase red to validatetdd_workflow.py --phase green to validateInput source function (math_utils.py):
def divide(a: float, b: float) -> float:
if b == 0:
raise ValueError("Cannot divide by zero")
return a / b
Command:
python scripts/test_generator.py --input math_utils.py --framework pytest
Generated test output (test_math_utils.py):
import pytest
from math_utils import divide
class TestDivide:
def test_divide_positive_numbers(self):
assert divide(10, 2) == 5.0
def test_divide_negative_numerator(self):
assert divide(-10, 2) == -5.0
def test_divide_float_result(self):
assert divide(1, 3) == pytest.approx(0.333, rel=1e-3)
def test_divide_by_zero_raises_value_error(self):
with pytest.raises(ValueError, match="Cannot divide by zero"):
divide(10, 0)
def test_divide_zero_numerator(self):
assert divide(0, 5) == 0.0
Command:
python scripts/coverage_analyzer.py --report lcov.info --threshold 80
Sample output:
Coverage Report — Overall: 63% (threshold: 80%)
P0 — Critical gaps (uncovered error paths):
auth/login.py:42-58 handle_expired_token() 0% covered
payments/process.py:91-110 handle_payment_failure() 0% covered
P1 — High-value gaps (core logic branches):
users/service.py:77 update_profile() — else branch 0% covered
orders/cart.py:134 apply_discount() — zero-qty guard 0% covered
P2 — Low-risk gaps (utility / helper functions):
utils/formatting.py:12 format_currency() 0% covered
Recommended: Generate tests for P0 items first to reach 80% threshold.
| Tool | Purpose | Usage |
|---|---|---|
test_generator.py | Generate test cases from code/requirements | python scripts/test_generator.py --input source.py --framework pytest |
coverage_analyzer.py | Parse and analyze coverage reports | python scripts/coverage_analyzer.py --report lcov.info --threshold 80 |
tdd_workflow.py | Guide red-green-refactor cycles | python scripts/tdd_workflow.py --phase red --test test_auth.py |
fixture_generator.py | Generate test data and mocks | python scripts/fixture_generator.py --entity User --count 5 |
Additional scripts: framework_adapter.py (convert between frameworks), metrics_calculator.py (quality metrics), format_detector.py (detect language/framework), output_formatter.py (CLI/desktop/CI output).
For Test Generation:
For Coverage Analysis:
For TDD Workflow:
| Scope | Details |
|---|---|
| Unit test focus | Integration and E2E tests require different patterns |
| Static analysis | Cannot execute tests or measure runtime behavior |
| Language support | Best for TypeScript, JavaScript, Python, Java |
| Report formats | LCOV, JSON, XML only; other formats need conversion |
| Generated tests | Provide scaffolding; require human review for complex logic |
When to use other tools: