fix+refactor(vcs): fix HEAD filter bug and effectify VcsService (#17829)

packages/opencode/test/file/watcher.test.ts

@@ -2,10 +2,10 @@ import { $ } from "bun"
 import { afterEach, describe, expect, test } from "bun:test"
 import fs from "fs/promises"
 import path from "path"
-import { ConfigProvider, Deferred, Effect, Fiber, Layer, ManagedRuntime, Option } from "effect"
+import { Deferred, Effect, Fiber, Option } from "effect"
 import { tmpdir } from "../fixture/fixture"
+import { watcherConfigLayer, withServices } from "../fixture/instance"
 import { FileWatcher, FileWatcherService } from "../../src/file/watcher"
-import { InstanceContext } from "../../src/effect/instances"
 import { Instance } from "../../src/project/instance"
 import { GlobalBus } from "../../src/bus/global"
 
@@ -16,35 +16,21 @@ const describeWatcher = FileWatcher.hasNativeBinding() && !process.env.CI ? desc
 // Helpers
 // ---------------------------------------------------------------------------
 
-const configLayer = ConfigProvider.layer(
-  ConfigProvider.fromUnknown({
-    OPENCODE_EXPERIMENTAL_FILEWATCHER: "true",
-    OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER: "false",
-  }),
-)
-
 type BusUpdate = { directory?: string; payload: { type: string; properties: WatcherEvent } }
 type WatcherEvent = { file: string; event: "add" | "change" | "unlink" }
 
-/** Run `body` with a live FileWatcherService. Runtime is acquired/released via Effect.scoped. */
+/** Run `body` with a live FileWatcherService. */
 function withWatcher<E>(directory: string, body: Effect.Effect<void, E>) {
-  return Instance.provide({
+  return withServices(
     directory,
-    fn: () =>
-      Effect.gen(function* () {
-        const ctx = Layer.sync(InstanceContext, () =>
-          InstanceContext.of({ directory: Instance.directory, project: Instance.project }),
-        )
-        const layer = Layer.fresh(FileWatcherService.layer).pipe(Layer.provide(ctx), Layer.provide(configLayer))
-        const rt = yield* Effect.acquireRelease(
-          Effect.sync(() => ManagedRuntime.make(layer)),
-          (rt) => Effect.promise(() => rt.dispose()),
-        )
-        yield* Effect.promise(() => rt.runPromise(FileWatcherService.use((s) => s.init())))
-        yield* ready(directory)
-        yield* body
-      }).pipe(Effect.scoped, Effect.runPromise),
-  })
+    FileWatcherService.layer,
+    async (rt) => {
+      await rt.runPromise(FileWatcherService.use((s) => s.init()))
+      await Effect.runPromise(ready(directory))
+      await Effect.runPromise(body)
+    },
+    { provide: [watcherConfigLayer] },
+  )
 }
 
 function listen(directory: string, check: (evt: WatcherEvent) => boolean, hit: (evt: WatcherEvent) => void) {

packages/opencode/test/fixture/instance.ts

@@ -0,0 +1,47 @@
+import { ConfigProvider, Layer, ManagedRuntime } from "effect"
+import { InstanceContext } from "../../src/effect/instance-context"
+import { Instance } from "../../src/project/instance"
+
+/** ConfigProvider that enables the experimental file watcher. */
+export const watcherConfigLayer = ConfigProvider.layer(
+  ConfigProvider.fromUnknown({
+    OPENCODE_EXPERIMENTAL_FILEWATCHER: "true",
+    OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER: "false",
+  }),
+)
+
+/**
+ * Boot an Instance with the given service layers and run `body` with
+ * the ManagedRuntime. Cleanup is automatic — the runtime is disposed
+ * and Instance context is torn down when `body` completes.
+ *
+ * Layers may depend on InstanceContext (provided automatically).
+ * Pass extra layers via `options.provide` (e.g. ConfigProvider.layer).
+ */
+export function withServices<S>(
+  directory: string,
+  layer: Layer.Layer<S, any, InstanceContext>,
+  body: (rt: ManagedRuntime.ManagedRuntime<S, never>) => Promise<void>,
+  options?: { provide?: Layer.Layer<never>[] },
+) {
+  return Instance.provide({
+    directory,
+    fn: async () => {
+      const ctx = Layer.sync(InstanceContext, () =>
+        InstanceContext.of({ directory: Instance.directory, project: Instance.project }),
+      )
+      let resolved: Layer.Layer<S> = Layer.fresh(layer).pipe(Layer.provide(ctx)) as any
+      if (options?.provide) {
+        for (const l of options.provide) {
+          resolved = resolved.pipe(Layer.provide(l)) as any
+        }
+      }
+      const rt = ManagedRuntime.make(resolved)
+      try {
+        await body(rt)
+      } finally {
+        await rt.dispose()
+      }
+    },
+  })
+}

packages/opencode/test/project/vcs.test.ts

@@ -0,0 +1,117 @@
+import { $ } from "bun"
+import { afterEach, describe, expect, test } from "bun:test"
+import fs from "fs/promises"
+import path from "path"
+import { Layer, ManagedRuntime } from "effect"
+import { tmpdir } from "../fixture/fixture"
+import { watcherConfigLayer, withServices } from "../fixture/instance"
+import { FileWatcher, FileWatcherService } from "../../src/file/watcher"
+import { Instance } from "../../src/project/instance"
+import { GlobalBus } from "../../src/bus/global"
+import { Vcs, VcsService } from "../../src/project/vcs"
+
+// Skip in CI — native @parcel/watcher binding needed
+const describeVcs = FileWatcher.hasNativeBinding() && !process.env.CI ? describe : describe.skip
+
+// ---------------------------------------------------------------------------
+// Helpers
+// ---------------------------------------------------------------------------
+
+function withVcs(
+  directory: string,
+  body: (rt: ManagedRuntime.ManagedRuntime<FileWatcherService | VcsService, never>) => Promise<void>,
+) {
+  return withServices(
+    directory,
+    Layer.merge(FileWatcherService.layer, VcsService.layer),
+    async (rt) => {
+      await rt.runPromise(FileWatcherService.use((s) => s.init()))
+      await rt.runPromise(VcsService.use((s) => s.init()))
+      await Bun.sleep(200)
+      await body(rt)
+    },
+    { provide: [watcherConfigLayer] },
+  )
+}
+
+type BranchEvent = { directory?: string; payload: { type: string; properties: { branch?: string } } }
+
+/** Wait for a Vcs.Event.BranchUpdated event on GlobalBus */
+function nextBranchUpdate(directory: string, timeout = 5000) {
+  return new Promise<string | undefined>((resolve, reject) => {
+    const timer = setTimeout(() => {
+      GlobalBus.off("event", on)
+      reject(new Error("timed out waiting for BranchUpdated event"))
+    }, timeout)
+
+    function on(evt: BranchEvent) {
+      if (evt.directory !== directory) return
+      if (evt.payload.type !== Vcs.Event.BranchUpdated.type) return
+      clearTimeout(timer)
+      GlobalBus.off("event", on)
+      resolve(evt.payload.properties.branch)
+    }
+
+    GlobalBus.on("event", on)
+  })
+}
+
+// ---------------------------------------------------------------------------
+// Tests
+// ---------------------------------------------------------------------------
+
+describeVcs("Vcs", () => {
+  afterEach(() => Instance.disposeAll())
+
+  test("branch() returns current branch name", async () => {
+    await using tmp = await tmpdir({ git: true })
+
+    await withVcs(tmp.path, async (rt) => {
+      const branch = await rt.runPromise(VcsService.use((s) => s.branch()))
+      expect(branch).toBeDefined()
+      expect(typeof branch).toBe("string")
+    })
+  })
+
+  test("branch() returns undefined for non-git directories", async () => {
+    await using tmp = await tmpdir()
+
+    await withVcs(tmp.path, async (rt) => {
+      const branch = await rt.runPromise(VcsService.use((s) => s.branch()))
+      expect(branch).toBeUndefined()
+    })
+  })
+
+  test("publishes BranchUpdated when .git/HEAD changes", async () => {
+    await using tmp = await tmpdir({ git: true })
+    const branch = `test-${Math.random().toString(36).slice(2)}`
+    await $`git branch ${branch}`.cwd(tmp.path).quiet()
+
+    await withVcs(tmp.path, async () => {
+      const pending = nextBranchUpdate(tmp.path)
+
+      const head = path.join(tmp.path, ".git", "HEAD")
+      await fs.writeFile(head, `ref: refs/heads/${branch}\n`)
+
+      const updated = await pending
+      expect(updated).toBe(branch)
+    })
+  })
+
+  test("branch() reflects the new branch after HEAD change", async () => {
+    await using tmp = await tmpdir({ git: true })
+    const branch = `test-${Math.random().toString(36).slice(2)}`
+    await $`git branch ${branch}`.cwd(tmp.path).quiet()
+
+    await withVcs(tmp.path, async (rt) => {
+      const pending = nextBranchUpdate(tmp.path)
+
+      const head = path.join(tmp.path, ".git", "HEAD")
+      await fs.writeFile(head, `ref: refs/heads/${branch}\n`)
+
+      await pending
+      const current = await rt.runPromise(VcsService.use((s) => s.branch()))
+      expect(current).toBe(branch)
+    })
+  })
+})