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Sarj Standards

Python · testing

no-sleep-in-test-body

python:no-sleep-in-test-body

Tests should synchronize on observable state instead of waiting a fixed duration.

Code
SARJ031
Default
error
Fix
none
Languages
python

Why

A fixed nonzero sleep makes test reliability and runtime depend on machine and CI timing.

Fix

Await the operation, wait on an event, or poll the expected condition with a bounded timeout.

Before / after

Executed by this rule’s unit tests.

Before

Test waits a fixed duration

tests/test_worker.py · focus
import asyncio

async def test_worker_finishes():
    start_worker()
    await asyncio.sleep(0.1)
    assert worker_finished()

After

Test waits for the completion signal

tests/test_worker.py · focus
async def test_worker_finishes():
    finished = start_worker()
    await finished.wait()
    assert worker_finished()

Limits

  • Only test paths and calls resolved to imported `time.sleep` or `asyncio.sleep` are analyzed.
  • Zero, computed, helper-owned, and bounded polling-loop sleeps are excluded.