refactor(core): move mercurial vcs into internal plugin (#44993)

packages/core/src/plugin/internal.ts

@@ -83,6 +83,7 @@ import { ProviderPlugins } from "./provider.js"
 import { WebSearchPlugins } from "./websearch/index.js"
 import { PluginRuntime } from "./runtime.js"
 import { SkillPlugin } from "./skill.js"
+import { VcsHgPlugin } from "./vcs/hg.js"
 import { SystemPromptPlugin } from "./system-prompt.js"
 import { VariantPlugin } from "./variant.js"
 import { VcsGitPlugin } from "./vcs/git.js"
@@ -241,6 +242,7 @@ const pre = [
   PlanPlugin.Plugin,
   CommandPlugin.Plugin,
   SkillPlugin.Plugin,
+  VcsHgPlugin.Plugin,
   ...SystemPromptPlugin.Plugins,
   ModelsDevPlugin,
   ...ProviderPlugins,

packages/core/src/plugin/vcs/hg.ts

@@ -1,13 +1,15 @@
-export * as VcsHg from "./hg.js"
+export * as VcsHgPlugin from "./hg.js"
 
 import path from "path"
 import { Effect } from "effect"
 import { ChildProcess } from "effect/unstable/process"
+import { define } from "@opencode-ai/plugin/effect/plugin"
 import { FileDiff } from "@opencode-ai/schema/file-diff"
 import { FileStatus, Info, Mode } from "@opencode-ai/schema/vcs"
 import { FSUtil } from "@opencode-ai/util/fs-util"
 import { AppProcess } from "@opencode-ai/util/process"
-import type { Adapter, DiffOptions } from "../vcs.js"
+import { Location } from "../../location.js"
+import type { Adapter, DiffOptions } from "../../vcs.js"
 import {
   addPatch,
   chunksByFile,
@@ -17,14 +19,40 @@ import {
   MAX_PATCH_BYTES,
   MAX_TOTAL_PATCH_BYTES,
   PATCH_CONTEXT_LINES,
-} from "./patch.js"
+} from "../../vcs/patch.js"
+
+export const Plugin = define({
+  id: "opencode.vcs.hg",
+  effect: Effect.fn("VcsHgPlugin")(function* (ctx) {
+    const location = yield* Location.Service
+    if (location.vcs?.type !== "hg") return
+
+    const processes = yield* AppProcess.Service
+    const fs = yield* FSUtil.Service
+    const adapter = make(processes, fs, {
+      directory: location.directory,
+      worktree: location.project.directory,
+    })
+
+    yield* ctx.vcs.transform((draft) => {
+      draft.add({
+        id: "hg",
+        name: "Mercurial",
+        info: () => adapter.info(),
+        branches: (input) => adapter.branches({ search: input.search, limit: input.limit }),
+        status: () => adapter.status(),
+        diff: (input) => adapter.diff(input.mode, { context: input.context }),
+      })
+    })
+  }),
+})
 
 /**
  * Mercurial adapter for the Vcs service. `hg diff --git` emits git-format
  * patches for tracked changes; untracked (`?`) and missing (`!`) files never
  * appear in `hg diff`, so their patches are synthesized from file contents.
  */
-export function make(
+function make(
   proc: AppProcess.Interface,
   fs: FSUtil.Interface,
   input: { directory: string; worktree: string },

packages/core/src/vcs.ts

@@ -10,10 +10,8 @@ import { VcsEvent } from "@opencode-ai/schema/vcs-event"
 import { makeLocationNode } from "@opencode-ai/util/effect/app-node"
 import { FSUtil } from "@opencode-ai/util/fs-util"
 import { Location } from "./location.js"
-import { AppProcess } from "@opencode-ai/util/process"
 import { Bus } from "./bus.js"
 import { State } from "./state.js"
-import { VcsHg } from "./vcs/hg.js"
 import { emptyPatch, MAX_TOTAL_PATCH_BYTES, PATCH_CONTEXT_LINES } from "./vcs/patch.js"
 
 export { BranchList, FileStatus, Info, Mode }
@@ -43,24 +41,14 @@ interface Data {
 
 export class Service extends Context.Service<Service, Interface>()("@opencode/Vcs") {}
 
-// Adapter seam: one working-copy implementation per VCS type, selected by the
-// resolved location. Locations without a supported VCS degrade to empty
-// results so callers never need to special-case.
-const adapter = (proc: AppProcess.Interface, fs: FSUtil.Interface, location: Location.Interface) => {
-  const scope = { directory: location.directory, worktree: location.project.directory }
-  if (location.vcs?.type === "hg") return VcsHg.make(proc, fs, scope)
-}
-
 const layer = Layer.effect(
   Service,
   Effect.gen(function* () {
-    const proc = yield* AppProcess.Service
     const fs = yield* FSUtil.Service
     const location = yield* Location.Service
     const bus = yield* Bus.Service
-    const native = adapter(proc, fs, location)
     const vcs = location.vcs
-    const current = { info: native ? yield* native.info() : ({ branch: {} } satisfies Info) }
+    const current: { info: Info } = { info: { branch: {} } }
     const scope = {
       directory: location.directory,
       worktree: location.project.directory,
@@ -102,9 +90,7 @@ const layer = Layer.effect(
       const provider = selected()
       const next: Info = provider
         ? yield* protect(provider, "info", provider.info(scope).pipe(Effect.flatMap(decodeInfo)), { branch: {} })
-        : native
-          ? yield* native.info()
-          : { branch: {} }
+        : { branch: {} }
       const changed = current.info.branch.current !== next.branch.current
       current.info = next
       if (changed) yield* bus.publish(VcsEvent.BranchUpdated, { branch: next.branch.current })
@@ -140,8 +126,7 @@ const layer = Layer.effect(
             provider.branches({ ...scope, ...options }).pipe(Effect.flatMap(decodeBranches)),
             [],
           )
-        if (!native) return []
-        return yield* native.branches(options)
+        return []
       }),
       status: Effect.fn("Vcs.status")(function* () {
         const provider = selected()
@@ -155,12 +140,11 @@ const layer = Layer.effect(
             ),
             [],
           )
-        if (!native) return []
-        return yield* native.status()
+        return []
       }),
       diff: Effect.fn("Vcs.diff")(function* (mode: Mode, options?: DiffOptions) {
         const provider = selected()
-        if (!provider) return native ? yield* native.diff(mode, options) : []
+        if (!provider) return []
         const rows = yield* protect(
           provider,
           "diff",
@@ -189,5 +173,5 @@ const layer = Layer.effect(
 export const node = makeLocationNode({
   service: Service,
   layer: layer,
-  deps: [AppProcess.node, FSUtil.node, Location.node, Bus.node],
+  deps: [FSUtil.node, Location.node, Bus.node],
 })

packages/core/test/vcs-hg.test.ts

@@ -4,21 +4,25 @@ import fs from "fs/promises"
 import path from "path"
 import { Effect, Fiber, Layer, Stream } from "effect"
 import { LayerNode } from "@opencode-ai/util/effect/layer-node"
+import { FSUtil } from "@opencode-ai/util/fs-util"
+import { AppProcess } from "@opencode-ai/util/process"
 import { Bus } from "@opencode-ai/core/bus"
 import { Location } from "@opencode-ai/core/location"
 import { AbsolutePath } from "@opencode-ai/core/schema"
 import { Vcs } from "@opencode-ai/core/vcs"
+import { VcsHgPlugin } from "@opencode-ai/core/plugin/vcs/hg"
 import { FileSystem } from "@opencode-ai/schema/filesystem"
 import { VcsEvent } from "@opencode-ai/schema/vcs-event"
 import { location } from "./fixture/location"
 import { tmpdir } from "./fixture/tmpdir"
 import { it } from "./lib/effect"
+import { host } from "./plugin/host"
 
 const describeHg = Bun.which("hg") ? describe : describe.skip
 
 const provide = (directory: string) =>
   Effect.provide(
-    LayerNode.compile(LayerNode.group([Vcs.node, Bus.node]), [
+    LayerNode.compile(LayerNode.group([Vcs.node, Bus.node, Location.node, AppProcess.node, FSUtil.node]), [
       [
         Location.node,
         Layer.succeed(
@@ -42,7 +46,19 @@ const withTmp = <A, E, R>(f: (directory: string) => Effect.Effect<A, E, R>) =>
 
 const withHg = <A, E, R>(f: (directory: string) => Effect.Effect<A, E, R>) =>
   withTmp((directory) =>
-    Effect.promise(() => hg(directory, "init")).pipe(Effect.andThen(f(directory).pipe(provide(directory)))),
+    Effect.promise(() => hg(directory, "init")).pipe(
+      Effect.andThen(
+        Effect.gen(function* () {
+          const vcs = yield* Vcs.Service
+          const context = host()
+          yield* VcsHgPlugin.Plugin.effect({
+            ...context,
+            vcs: { ...context.vcs, transform: vcs.transform, reload: vcs.reload },
+          })
+          return yield* f(directory)
+        }).pipe(provide(directory)),
+      ),
+    ),
   )
 
 async function hg(directory: string, ...args: string[]) {