feat(kotest): typesafe Kotest scenario DSL integration

[wilmveel]

What

New src:integration:kotest module that emits a typesafe Kotest scenario DSL next to the generated Kotlin models, via the IR KotestDslExtension. Endpoints, channels, and types each get a block-style entry point read through the generated name. Every builder entry point returns a Gen<…> — compose it into checkAll, or call()/send()/draw() a single value out of it:

// endpoint — request { } returns Gen<Request>; call() draws one and sends it
val response = CreateProduct.generate.request {
    body { sku = Arb.constant("SKU-001"); price = Arb.constant(29.95) }
}.call()

// channel — message { } returns Gen<Payload>; send() draws one and publishes it
Queue.generate.message { eventType = Arb.constant(CampaignEventType.ENDED) }.send()
Queue.generate.listen { expecting { event -> event.eventType shouldBe CREATED } }

// type — Gen<T> for a standalone record
val gen: Gen<TodoDto> = TodoDto.generate { name = Arb.constant("milk") }

// draw one value to inspect (response builders, or any of the above)
val canned: CreateProduct.Response201 = CreateProduct.generate.response201 { body = Arb.constant(p) }.draw()

Fields are pinned with kotest Gens; un-set fields are drawn by the Wirespec generator. call()/send() draw seeded by the per-test ambient RandomSource (installed by the endpoint/channel extensions), which also resolves the transport.

Shared builders

Every record has one reusable <Type>Builder, referenced by endpoint request bodies, channel payloads, and <Type>.generate alike rather than replicated per operation. Nested record fields expose a <field>Block { … } sub-block that opens the nested type's builder, so overrides compose to any depth.

<Type>.generate is a companion-object extension mirroring the endpoint/channel <X>.generate. Generated records have no companion, so the extension injects an empty companion object into each — the generate logic stays in the kotest package, keeping the model dependency-free.

Spring bridge

Both test extensions are framework-agnostic (no Spring/DI dependency); the module carries no Spring on its classpath:

• WirespecEndpointExtension — supply an endpoint context eagerly (WirespecEndpointContext, or transportation + serialization), or use the factory form: suspend factories for Wirespec.Transportation + Wirespec.Serialization, resolved per test.
• WirespecChannelExtension — the same, plus a managed overload for a stateful transport: suspend factories it builds once, resets per test (reset), and closes after the spec. A same-named generic factory keeps reset = { it.clear() } cast-free.

Each has a same-named factory function alongside its constructors, so named arguments (serialization = …, transport(ation) = …) select the factory form unambiguously. A caller wires its framework in those factories — the example resolves the server port, Wirespec.Serialization bean, and Kafka bootstrap servers from the Spring test context via testContextManager(). The managed channel extension builds its transport per spec (keyed by Spec), so a single instance is safe to register suite-wide.

The example registers everything once in a single io.kotest.provided.ProjectConfig — SpringExtension plus the two wirespec extensions — so specs carry no extension wiring (no @ApplyExtension, no in-body extension(...), no per-app subclass or @TestConfiguration bean); they just declare @SpringBootTest / @EmbeddedKafka.

Build wiring

• Register src:integration:kotest in settings.gradle.kts; add kotest-property + kotlinx-coroutines-core to the catalog.
• Move the generated Wirespec.kt runtime to commonMain so this KMP module can reference the Wirespec.* interfaces from its own commonMain.

Example & testing

• examples/gradle-kotest — end-to-end Spring + embedded-Kafka app driving the DSL against a live server and a real broker.
• KotestDslExtensionTest asserts the emitted DSL (Gen<> entry points, builder dedup, companion injection); the generated output was also compiled with kotlinc against the real runtime for a flat and a nested/channel spec.

🤖 Generated with Claude Code

[wilmveel]

isAsync

[wilmveel]

isAsync

[jerrevanveluw]

Is the example added to the pipeline?

[wilmveel]

use reserved keword from emitter

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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