Testing conventions

Purpose

These conventions keep the client-rewrite suite deterministic, reproducible, and portable across implementations.

Test locations

Test type	Location	Naming
JVM unit and contract tests	`app/src/test/`	`*Test.kt`
Shared deterministic fakes and fixtures	`app/src/test/**/testsupport/`	Descriptive fixture name
Robolectric tests	`app/src/test/`	`*RobolectricTest.kt`
Android instrumented tests	`app/src/androidTest/`	`*InstrumentedTest.kt`
Coverage-tool tests	`tools/coverage/`	`test_*.py`
Interoperability fixtures	`app/src/test/resources/contracts/`	Protocol and version in filename

Required behavior

Tests must not use arbitrary sleeps. Advance a fake clock or coroutine test scheduler instead.
Tests must not require public relays, internet access, Bluetooth hardware, or a user's persisted data.
Time, randomness, dispatchers, storage, and transports must be injectable in code exercised by state-machine tests.
Randomized failures must print a reproduction seed. Use TEST_SEED for a specific replay.
Mutable byte arrays returned by fixtures and fakes must be defensively copied.
Negative security tests must assert fail-closed behavior.
Protocol round trips must be paired with literal golden vectors for critical externally visible formats.
Asynchronous tests must have a deterministic completion condition and a bounded timeout.
A fixed bug must retain its smallest reproducing input as a regression test.

Naming

Test names should describe observable behavior:

kotlin

@Test
fun `replayed ciphertext is rejected without advancing receive state`() {
    // ...
}

Avoid names tied to private methods or temporary implementation structure.

Fixtures and seeds

Reusable Kotlin fixtures live under com.bitchat.android.testsupport. ReproducibleTestSeed resolves TEST_SEED and provides a reproduction hint:

TEST_SEED=12345 ./gradlew clientRewriteContractTest

Never use production keys, contact information, messages, or other user data in fixtures.

Coverage

Run the full report and non-regression floor:

./gradlew clientRewriteContractTest

Reports are written to:

app/build/reports/jacoco/jacocoTestReport/jacocoTestReport.xml
app/build/reports/jacoco/jacocoTestReport/html/

Check executable production lines changed from the base branch:

COVERAGE_BASE_REF=origin/main ./gradlew checkChangedLineCoverage

Generated resource classes, Compose-generated singleton classes, platform bridges, and vendored Noise code are excluded from first-party coverage metrics.

Quarantine and skips

A flaky test must be fixed, not silently retried.
A temporary quarantine must include an issue and removal condition.
Unexpected skips fail review. Existing skips must be restored or replaced by equivalent coverage.