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Fix: Prevent flaky tests with random values in parametrize #3

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Merged
MKaczkow merged 2 commits into from
Apr 26, 2026
Merged

Fix: Prevent flaky tests with random values in parametrize #3

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183866a
fix: seed random generator to prevent flaky parametrized tests
denini08 Apr 21, 2026
f7bf7a7
fix: seed before test run to prevent flaky parametrized tests
denini08 Apr 21, 2026
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15 changes: 6 additions & 9 deletions testing/pytest/test_employee_pytest.py
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Original file line number Diff line number Diff line change
Expand Up @@ -3,6 +3,11 @@
import pytest
from employee import Employee

# seeded at import time so parametrize decorator gets deterministic values (avoid )
# without seed, random.randint() produces different values each run (flaky tests)
_rng = random.Random(42)
_random_test_cases = [(_rng.randint(0, 100),) * 2 for _ in range(9)]


# pytest doesn't require TestCase to inherit from anything
class EmployeeTestCase:
Expand Down Expand Up @@ -40,15 +45,7 @@ def test_pay(employee):
(100, 100),
(1999, 1999),
(2022, 2022),
tuple([random.randint(0, 100)] * 2),
tuple([random.randint(0, 100)] * 2),
tuple([random.randint(0, 100)] * 2),
tuple([random.randint(0, 100)] * 2),
tuple([random.randint(0, 100)] * 2),
tuple([random.randint(0, 100)] * 2),
tuple([random.randint(0, 100)] * 2),
tuple([random.randint(0, 100)] * 2),
tuple([random.randint(0, 100)] * 2),
*_random_test_cases,
],
)
def test_very_simple(given_value, expected_value):
Expand Down
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