HighFile-scopeKotlin Plug & play

Kotlin coroutines: use runTest and avoid Thread.sleep

Test suspend code with kotlinx-coroutines-test runTest {} and virtual time (advanceUntilIdle()); do not block with Thread.sleep.

Why this matters

Virtual time makes async tests fast and deterministic.

Side-by-side examples engineers can pattern-match during review.

Avoid

@Test fun loads(){\n Thread.sleep(1000)\n val v = runBlocking { load() }\n assertTrue(v > 0)\n}

Prefer

@Test fun loads() = runTest {
 val v = load()
 advanceUntilIdle()
 assertTrue(v > 0)
}

Good

@Test fun x() = runTest { advanceUntilIdle() }

Bad

Thread.sleep(500); // in test

From the same buckets as this rule.

Critical
No live network or DB in unit tests—use fakes/mocks
Unit tests must stub or fake external HTTP/DB calls; allow real I/O only in integration/e2e tests tagged accordingly.
testing-qualityperformance-efficiency+1
High
Behavioral changes must add or update tests
If files under src/ change behavior, the PR must include tests/ updates or a PR description line no-tests: <reason> explaining why tests are unaffected.
testing-qualitypr-hygiene
High
Block real PAN/SAD in fixtures and test data
Reject PRs adding real PAN/CVV in fixtures, seeds, or mocks. Only use Luhn-valid test PANs from the gateway or opaque tokens (e.g., tok_) and never include CVV. Add a check to fail if a PAN regex is matched. (PCI DSS data minimization)
compliance-pci-dsstesting-quality+1