Add vitest layer api (#3689)

.changeset/dull-laws-joke.md

@@ -0,0 +1,44 @@
+---
+"@effect/vitest": patch
+---
+
+add layer api to `@effect/vitest`
+
+This allows you to share a `Layer` between multiple tests, optionally wrapping
+the tests in a `describe` block.
+
+```ts
+import { expect, layer } from "@effect/vitest"
+import { Context, Effect, Layer } from "effect"
+
+class Foo extends Context.Tag("Foo")<Foo, "foo">() {
+  static Live = Layer.succeed(Foo, "foo")
+}
+
+class Bar extends Context.Tag("Bar")<Bar, "bar">() {
+  static Live = Layer.effect(
+    Bar,
+    Effect.map(Foo, () => "bar" as const)
+  )
+}
+
+layer(Foo.Live)("layer", (it) => {
+  it.effect("adds context", () =>
+    Effect.gen(function* () {
+      const foo = yield* Foo
+      expect(foo).toEqual("foo")
+    })
+  )
+
+  it.layer(Bar.Live)("nested", (it) => {
+    it.effect("adds context", () =>
+      Effect.gen(function* () {
+        const foo = yield* Foo
+        const bar = yield* Bar
+        expect(foo).toEqual("foo")
+        expect(bar).toEqual("bar")
+      })
+    )
+  })
+})
+```

packages/vitest/src/index.ts

@@ -3,6 +3,7 @@
  */
 import type * as Duration from "effect/Duration"
 import type * as Effect from "effect/Effect"
+import type * as Layer from "effect/Layer"
 import type * as Scope from "effect/Scope"
 import type * as TestServices from "effect/TestServices"
 import * as V from "vitest"
@@ -47,7 +48,26 @@ export namespace Vitest {
       cases: ReadonlyArray<T>
     ) => <A, E>(name: string, self: TestFunction<A, E, R, Array<T>>, timeout?: number | V.TestOptions) => void
   }
+
+  /**
+   * @since 1.0.0
+   */
+  export interface Methods<R = never> extends API {
+    readonly effect: Vitest.Tester<TestServices.TestServices | R>
+    readonly live: Vitest.Tester<R>
+    readonly flakyTest: <A, E, R2>(
+      self: Effect.Effect<A, E, R2>,
+      timeout?: Duration.DurationInput
+    ) => Effect.Effect<A, never, R2>
+    readonly scoped: Vitest.Tester<TestServices.TestServices | Scope.Scope | R>
+    readonly scopedLive: Vitest.Tester<Scope.Scope | R>
+    readonly layer: <R2, E>(layer: Layer.Layer<R2, E, R>) => {
+      (f: (it: Vitest.Methods<R | R2>) => void): void
+      (name: string, f: (it: Vitest.Methods<R | R2>) => void): void
+    }
+  }
 }
+
 /**
  * @since 1.0.0
  */
@@ -73,6 +93,56 @@ export const live: Vitest.Tester<never> = internal.live
  */
 export const scopedLive: Vitest.Tester<Scope.Scope> = internal.scopedLive
 
+/**
+ * Share a `Layer` between multiple tests, optionally wrapping
+ * the tests in a `describe` block if a name is provided.
+ *
+ * @since 1.0.0
+ *
+ * ```ts
+ * import { expect, layer } from "@effect/vitest"
+ * import { Context, Effect, Layer } from "effect"
+ *
+ * class Foo extends Context.Tag("Foo")<Foo, "foo">() {
+ *   static Live = Layer.succeed(Foo, "foo")
+ * }
+ *
+ * class Bar extends Context.Tag("Bar")<Bar, "bar">() {
+ *   static Live = Layer.effect(
+ *     Bar,
+ *     Effect.map(Foo, () => "bar" as const)
+ *   )
+ * }
+ *
+ * layer(Foo.Live)("layer", (it) => {
+ *   it.effect("adds context", () =>
+ *     Effect.gen(function* () {
+ *       const foo = yield* Foo
+ *       expect(foo).toEqual("foo")
+ *     })
+ *   )
+ *
+ *   it.layer(Bar.Live)("nested", (it) => {
+ *     it.effect("adds context", () =>
+ *       Effect.gen(function* () {
+ *         const foo = yield* Foo
+ *         const bar = yield* Bar
+ *         expect(foo).toEqual("foo")
+ *         expect(bar).toEqual("bar")
+ *       })
+ *     )
+ *   })
+ * })
+ * ```
+ */
+export const layer: <R, E>(
+  layer_: Layer.Layer<R, E>,
+  memoMap?: Layer.MemoMap
+) => {
+  (f: (it: Vitest.Methods<R>) => void): void
+  (name: string, f: (it: Vitest.Methods<R>) => void): void
+} = internal.layer
+
 /**
  * @since 1.0.0
  */
@@ -82,12 +152,12 @@ export const flakyTest: <A, E, R>(
 ) => Effect.Effect<A, never, R> = internal.flakyTest
 
 /** @ignored */
-const methods = { effect, live, flakyTest, scoped, scopedLive } as const
+const methods = { effect, live, flakyTest, scoped, scopedLive, layer } as const
 
 /**
  * @since 1.0.0
  */
-export const it: API & typeof methods = Object.assign(V.it, methods)
+export const it: Vitest.Methods = Object.assign(V.it, methods)
 
 /**
  * @since 1.0.0

packages/vitest/src/internal.ts

@@ -11,31 +11,28 @@ import * as Fiber from "effect/Fiber"
 import { flow, identity, pipe } from "effect/Function"
 import * as Layer from "effect/Layer"
 import * as Logger from "effect/Logger"
-import * as Runtime from "effect/Runtime"
 import * as Schedule from "effect/Schedule"
-import type * as Scope from "effect/Scope"
+import * as Scope from "effect/Scope"
 import * as TestEnvironment from "effect/TestContext"
 import type * as TestServices from "effect/TestServices"
 import * as Utils from "effect/Utils"
 import * as V from "vitest"
 import type * as Vitest from "./index.js"
 
-/** @internal */
-const runTest = (ctx: Vitest.TaskContext) => <E, A>(effect: Effect.Effect<A, E>) =>
+const runPromise = (ctx?: Vitest.TaskContext) => <E, A>(effect: Effect.Effect<A, E>) =>
   Effect.gen(function*() {
     const exitFiber = yield* Effect.fork(Effect.exit(effect))
-    const runtime = yield* Effect.runtime()
 
-    ctx.onTestFinished(() =>
+    ctx?.onTestFinished(() =>
       Fiber.interrupt(exitFiber).pipe(
         Effect.asVoid,
-        Runtime.runPromise(runtime)
+        Effect.runPromise
       )
     )
 
     const exit = yield* Fiber.join(exitFiber)
     if (Exit.isSuccess(exit)) {
-      return () => {}
+      return () => exit.value
     } else {
       const errors = Cause.prettyErrors(exit.cause)
       for (let i = 1; i < errors.length; i++) {
@@ -47,6 +44,10 @@ const runTest = (ctx: Vitest.TaskContext) => <E, A>(effect: Effect.Effect<A, E>)
     }
   }).pipe(Effect.runPromise).then((f) => f())
 
+/** @internal */
+const runTest = (ctx?: Vitest.TaskContext) => <E, A>(effect: Effect.Effect<A, E>) =>
+  runPromise(ctx)(Effect.asVoid(effect))
+
 /** @internal */
 const TestEnv = TestEnvironment.TestContext.pipe(
   Layer.provide(Logger.remove(Logger.defaultLogger))
@@ -98,6 +99,71 @@ const makeTester = <R>(
   return Object.assign(f, { skip, skipIf, runIf, only, each })
 }
 
+/** @internal */
+export const layer = <R, E>(layer_: Layer.Layer<R, E>, memoMap?: Layer.MemoMap): {
+  (f: (it: Vitest.Vitest.Methods<R>) => void): void
+  (name: string, f: (it: Vitest.Vitest.Methods<R>) => void): void
+} =>
+(
+  ...args: [name: string, f: (it: Vitest.Vitest.Methods<R>) => void] | [f: (it: Vitest.Vitest.Methods<R>) => void]
+) => {
+  memoMap = memoMap ?? Effect.runSync(Layer.makeMemoMap)
+  const scope = Effect.runSync(Scope.make())
+  const runtimeEffect = Layer.toRuntimeWithMemoMap(layer_, memoMap).pipe(
+    Scope.extend(scope),
+    Effect.orDie,
+    Effect.cached,
+    Effect.runSync
+  )
+
+  const it: Vitest.Vitest.Methods<R> = Object.assign(V.it, {
+    effect: makeTester<TestServices.TestServices | R>((effect) =>
+      Effect.flatMap(runtimeEffect, (runtime) =>
+        effect.pipe(
+          Effect.provide(runtime),
+          Effect.provide(TestEnv)
+        ))
+    ),
+    scoped: makeTester<TestServices.TestServices | Scope.Scope | R>((effect) =>
+      Effect.flatMap(runtimeEffect, (runtime) =>
+        effect.pipe(
+          Effect.scoped,
+          Effect.provide(runtime),
+          Effect.provide(TestEnv)
+        ))
+    ),
+    live: makeTester<R>((effect) =>
+      Effect.flatMap(
+        runtimeEffect,
+        (runtime) => Effect.provide(effect, runtime)
+      )
+    ),
+    scopedLive: makeTester<Scope.Scope | R>((effect) =>
+      Effect.flatMap(runtimeEffect, (runtime) =>
+        effect.pipe(
+          Effect.scoped,
+          Effect.provide(runtime)
+        ))
+    ),
+    flakyTest,
+    layer<R2, E2>(nestedLayer: Layer.Layer<R2, E2, R>) {
+      return layer(Layer.provideMerge(nestedLayer, layer_), memoMap)
+    }
+  })
+
+  if (args.length === 1) {
+    V.beforeAll(() => runPromise()(Effect.asVoid(runtimeEffect)))
+    V.afterAll(() => runPromise()(Scope.close(scope, Exit.void)))
+    return args[0](it)
+  }
+
+  return V.describe(args[0], () => {
+    V.beforeAll(() => runPromise()(Effect.asVoid(runtimeEffect)))
+    V.afterAll(() => runPromise()(Scope.close(scope, Exit.void)))
+    return args[1](it)
+  })
+}
+
 /** @internal */
 export const effect = makeTester<TestServices.TestServices>(Effect.provide(TestEnv))
 

packages/vitest/test/index.test.ts

@@ -1,5 +1,5 @@
-import { expect, it } from "@effect/vitest"
-import { Effect } from "effect"
+import { afterAll, describe, expect, it, layer } from "@effect/vitest"
+import { Context, Effect, Layer } from "effect"
 
 it.live(
   "live %s",
@@ -85,3 +85,66 @@ it.scopedLive("interrupts on timeout", (ctx) =>
     )
     yield* Effect.sleep(1000)
   }), { timeout: 100, fails: true })
+
+class Foo extends Context.Tag("Foo")<Foo, "foo">() {
+  static Live = Layer.succeed(Foo, "foo")
+}
+
+class Bar extends Context.Tag("Bar")<Bar, "bar">() {
+  static Live = Layer.effect(Bar, Effect.map(Foo, () => "bar" as const))
+}
+
+layer(Foo.Live)("layer", (it) => {
+  it.effect("adds context", () =>
+    Effect.gen(function*() {
+      const foo = yield* Foo
+      expect(foo).toEqual("foo")
+    }))
+
+  it.layer(Bar.Live)("nested", (it) => {
+    it.effect("adds context", () =>
+      Effect.gen(function*() {
+        const foo = yield* Foo
+        const bar = yield* Bar
+        expect(foo).toEqual("foo")
+        expect(bar).toEqual("bar")
+      }))
+  })
+
+  it.layer(Bar.Live)((it) => {
+    it.effect("without name", () =>
+      Effect.gen(function*() {
+        const foo = yield* Foo
+        const bar = yield* Bar
+        expect(foo).toEqual("foo")
+        expect(bar).toEqual("bar")
+      }))
+  })
+
+  describe("release", () => {
+    let released = false
+    afterAll(() => {
+      expect(released).toEqual(true)
+    })
+
+    class Scoped extends Context.Tag("Scoped")<Scoped, "scoped">() {
+      static Live = Layer.scoped(
+        Scoped,
+        Effect.acquireRelease(
+          Effect.succeed("scoped" as const),
+          () => Effect.sync(() => released = true)
+        )
+      )
+    }
+
+    it.layer(Scoped.Live)((it) => {
+      it.effect("adds context", () =>
+        Effect.gen(function*() {
+          const foo = yield* Foo
+          const scoped = yield* Scoped
+          expect(foo).toEqual("foo")
+          expect(scoped).toEqual("scoped")
+        }))
+    })
+  })
+})