Emily Chen·
Realistic test data, no foo/bar - generated the suite I kept putting off
Generate comprehensive unit tests including edge cases, boundary conditions, parameterized tests, and mocking setup from source code.
Unit Test Generator Pro
Act as a test-driven development expert. Generate a complete, production-ready unit test suite for the following code.
**Source Code to Test:**
```
{{source_code}}
```
**Language & Testing Framework:**
{{language_framework}}
**Mocking Framework:**
{{mocking_framework}}
**Coverage Target:**
{{coverage_target}}
Requirements for the test suite:
1. Test every public method with happy path scenarios
2. Include boundary/edge cases (empty input, maximum values, nulls, special characters)
3. Include error cases and exception handling tests
4. Use parameterized tests where appropriate to reduce duplication
5. Mock all external dependencies (databases, APIs, file system, clock)
6. Follow AAA pattern (Arrange-Act-Assert) with clear comments
7. Include test descriptions/docstrings explaining what each test validates
8. Aim for {{coverage_target}}% line coverage minimum
9. Use realistic test data, not foo/bar placeholders
10. Include setup and teardown if needed
Output ONLY the complete test file(s) ready to compile/run. No explanatory text outside code comments.
Ergebnisse
```python
import pytest
from datetime import datetime
from billing import calculate_invoice, InvalidLineItem
class TestCalculateInvoice:
def test_sums_line_items_with_tax(self):
# Arrange
items = [{"price": 1000, "qty": 2}, {"price": 500, "qty": 1}]
# Act
result = calculate_invoice(items, tax_rate=0.19)
# Assert
assert result.total == 2975 # 2500 + 19% tax
@pytest.mark.parametrize("items,expected", [
([], 0), # empty invoice
([{"price": 0, "qty": 5}], 0), # zero-priced item
([{"price": 999_999, "qty": 99}], 98_999_901), # large values
])
def test_edge_case_totals(self, items, expected):
assert calculate_invoice(items, tax_rate=0.0).total == expected
def test_raises_on_negative_quantity(self):
with pytest.raises(InvalidLineItem, match="qty must be positive"):
calculate_invoice([{"price": 100, "qty": -1}], tax_rate=0.0)
def test_uses_injected_clock_for_issued_at(self, mocker):
fixed = datetime(2026, 6, 1, 12, 0)
mocker.patch("billing.now", return_value=fixed)
result = calculate_invoice([{"price": 100, "qty": 1}], tax_rate=0.0)
assert result.issued_at == fixed
```
Modell: Claude Sonnet 4
48 Likes22 SavesScore: 40
4 Kommentare
Marco Rossi·
Sending this debugging, testing one to my whole team.
Luca Brunner·
Ran it on our repo and it worked first try, honestly impressed.
Ryan Mitchell·
How does this hold up under concurrency? Looks thread-safe to me but curious.
Tobias Keller·
The diff summary format is so much easier to scan than a wall of code.