Rig.TUnit.Caching.Fusion 0.1.0-beta.2

Rig.TUnit.Caching.Fusion

FusionCache provider — L1 in-memory + optional L2 distributed + backplane, with fail-safe, eager refresh, and tag invalidation.

What this package is

The Rig.TUnit adapter for FusionCache. FusionCacheFixture configures an IFusionCache with production-shape defaults (fail-safe enabled, eager-refresh at 80 % TTL, 60 s default duration) and exposes FailSafeHelper + EagerRefreshHelper — pure decision-logic predicates that tests use to assert the cache should apply fail-safe or trigger an eager refresh, without racing the scheduler.

No container required — FusionCache is in-process. For the L2 distributed tier, pair with Rig.TUnit.Caching.Redis.

When to use it

• Testing services that use FusionCache in production.
• Verifying fail-safe fallback triggers when the underlying loader throws.
• Asserting eager-refresh enters the right window near TTL expiry.
• Not for: plain IMemoryCache — use Rig.TUnit.Caching.Memory.

Prerequisites

• .NET 10 SDK
• ZiggyCreatures.FusionCache 2.x (transitive)

Quick start

using Rig.TUnit.Caching.Fusion.Fixtures;

await using var fx = new FusionCacheFixture();
await fx.InitializeAsync();

var key = $"k-{Guid.NewGuid():N}";
var value = await fx.Cache.GetOrSetAsync<string>(key, async (_, _) =>
{
 await Task.Yield();
 return "computed";
});

Options

Section name: RigTUnit:FusionCache.

Fixture + helper APIs

• Rig.TUnit.Caching.Fusion.Fixtures.FusionCacheFixture
• Rig.TUnit.Caching.Fusion.Options.FusionCacheFixtureOptions
• Rig.TUnit.Caching.Fusion.Builder.FusionCacheRigBuilder
• Rig.TUnit.Caching.Fusion.Helpers.FailSafeHelper
• Rig.TUnit.Caching.Fusion.Helpers.EagerRefreshHelper

Per-test isolation

Per-fixture IFusionCache instance — each test owns its own cache graph. No state is shared across tests by default; pairing with the Redis L2 backplane adds the Redis key-prefix isolation pattern.

Parallelism + performance

• Zero container startup.
• GetOrSetAsync warm hit: ~500 ns.
• Stampede coalescing: ~50 µs for first-loader dogpile test.
• Safe under full parallelism.

Troubleshooting

• Fail-safe does not fire — check IsFailSafeEnabled = true AND FailSafeMaxDuration > 0 AND the loader threw (a null return is not a failure).
• Eager refresh fires too often — test's synthetic clock is running real wall time; wrap with ClockControl from Rig.TUnit.Caching to freeze.

See .

Provider quirks + edge cases

• FusionCache's adaptive caching can return a stale value even when the loader succeeded — by design (for fail-safe). Tests asserting "always fresh" must disable it.
• Eager refresh is fire-and-forget; the current caller still gets the cached value while a background refresh runs. Tests racing this boundary must poll, not assume.

Benchmarks

See ; baseline in benchmarks/baseline-005.json.

Related docs

• Family base:

License

MIT. See .