do not flock until reify

packages/opencode/src/npm/effect.ts

@@ -63,8 +63,17 @@ interface ArboristTree {
   edgesOut: Map<string, { to?: ArboristNode }>
 }
 
+export const layer = Layer.effect(
+  Service,
+  Effect.gen(function* () {
+    const afs = yield* AppFileSystem.Service
+    const global = yield* Global.Service
+    const fs = yield* FileSystem.FileSystem
+    const flock = yield* EffectFlock.Service
+    const directory = (pkg: string) => path.join(global.cache, "packages", sanitize(pkg))
     const reify = (input: { dir: string; add?: string[] }) =>
       Effect.gen(function* () {
+        yield* flock.acquire(`npm-install:${input.dir}`)
         const { Arborist } = yield* Effect.promise(() => import("@npmcli/arborist"))
         const arborist = new Arborist({
           path: input.dir,
@@ -93,15 +102,6 @@ const reify = (input: { dir: string; add?: string[] }) =>
         }),
       )
 
-export const layer = Layer.effect(
-  Service,
-  Effect.gen(function* () {
-    const afs = yield* AppFileSystem.Service
-    const global = yield* Global.Service
-    const fs = yield* FileSystem.FileSystem
-    const flock = yield* EffectFlock.Service
-    const directory = (pkg: string) => path.join(global.cache, "packages", sanitize(pkg))
-
     const outdated = Effect.fn("Npm.outdated")(function* (pkg: string, cachedVersion: string) {
       const response = yield* Effect.tryPromise({
         try: () => fetch(`https://registry.npmjs.org/${pkg}`),
@@ -130,7 +130,6 @@ export const layer = Layer.effect(
 
     const add = Effect.fn("Npm.add")(function* (pkg: string) {
       const dir = directory(pkg)
-      yield* flock.acquire(`npm-install:${dir}`)
 
       const tree = yield* reify({ dir, add: [pkg] })
       const first = tree.edgesOut.values().next().value?.to
@@ -145,8 +144,6 @@ export const layer = Layer.effect(
       )
       if (!canWrite) return
 
-      yield* flock.acquire(`npm-install:${dir}`)
-
       yield* Effect.gen(function* () {
         const nodeModulesExists = yield* afs.existsSafe(path.join(dir, "node_modules"))
         if (!nodeModulesExists) {