Quality & Testing¶

Failover ships with a layered test strategy. The everyday build stays fast and hermetic; deeper, heavier checks are opt-in so they never slow down day-to-day development.

Two-tier default build¶

Tier	Pattern	Plugin	Context
Unit	`*Test.java`	Surefire	Pure Mockito / JUnit, no Spring context
Integration	`*IT.java`	Failsafe	`@SpringBootTest` against a real H2 database

Integration tests run with failover.store.async=false so writes are synchronous and assertions are deterministic. mvn clean verify runs both tiers — no Docker required.

Opt-in deep checks¶

These were added in the Phase 3 hardening pass (audit findings T-1 to T-4). Each is gated so the default build is unaffected:

Dialect integration tests

Real PostgreSQL / MySQL / MariaDB via Testcontainers, proving the native merge/upsert SQL. Profile dialect-its. (T-1)
Concurrency tests

Contention coverage for multi-tenant store routing and the async executor path. Part of the default build. (T-2)
Architecture tests

ArchUnit rules that enforce the decorator invariants the compiler cannot. Part of the default build. (T-3)
Mutation testing

PIT on the expiry + key boundary logic. Profile mutation. (T-4)

Command summary¶

# Default build — unit + H2 integration tests, no Docker
mvn clean verify

# Dialect ITs against real databases (requires Docker)
mvn -pl failover-store-jdbc -am -Pdialect-its verify

# Mutation testing on failover-core expiry/key packages
mvn -pl failover-core -am -Pmutation test

In CI the two heavy jobs (dialect-its, mutation) run as advisory, non-blocking checks; the H2 build remains the required gate.