fix(subprocess): hide Windows child windows

packages/subprocess/subprocess-local/README.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/subprocess/subprocess-local/README.md
-README.md: dd9edbc99578f5411fad993cf88f93429dc9cab2
-README.zh.md: 7bb43f7bbce5ef6b128edc9ef2104d35a5887845
+README.md: b0c96119d6e390afb30a6339d45d4ce186cd67de
+README.zh.md: 817e6ae149ea8d6c6062c7262ec374e259e530ef

packages/subprocess/subprocess-local/README.md

@@ -25,7 +25,7 @@ Mount `dsh-subprocess-local` in any composition that runs child processes on the
 <a id="use-this-package"></a>
 ## Use this package
 
-Mount the provider beside its consumers and start processes exactly as the subprocess service specifies; this package decides only how those processes run on the host.
+Mount the provider beside its consumers and start processes exactly as the subprocess service specifies; this package decides only how those processes run on the host. On Windows, non-terminal children start with their console windows hidden so background commands do not take focus.
 
 ### Mounting the provider
 

packages/subprocess/subprocess-local/README.zh.md

@@ -25,7 +25,7 @@ kind: "package-reference"
 <a id="use-this-package"></a>
 ## 使用本包
 
-把提供方与它的消费方挂载在同一组合中，并完全按子进程服务的规定启动进程；本包只决定这些进程在宿主机上如何运行。
+把提供方与它的消费方挂载在同一组合中，并完全按子进程服务的规定启动进程；本包只决定这些进程在宿主机上如何运行。在 Windows 上，非终端子进程会隐藏其控制台窗口，因此后台命令不会抢占焦点。
 
 ### 挂载提供方
 

packages/subprocess/subprocess-local/src/spawn.ts

@@ -7,7 +7,7 @@
  * @module dsh-subprocess-local/spawn
  */
 
-import { type ChildProcess, spawn, spawnSync } from 'node:child_process'
+import { type ChildProcess, type SpawnOptions, spawn, spawnSync } from 'node:child_process'
 import type { Readable } from 'node:stream'
 import { randomBytes } from 'node:crypto'
 import { closeSync, mkdtempSync, openSync, unlinkSync, writeSync } from 'node:fs'
@@ -26,6 +26,12 @@ import type {
 } from '@deepseek-ai/dsh-subprocess'
 import { linuxProcessGroupHasLiveMembers } from './process-inspector.ts'
 
+type SpawnProcess = (
+  program: string,
+  args: readonly string[],
+  options: SpawnOptions,
+) => ChildProcess
+
 /**
  * Build a child environment: explicit caller entries override the scrubbed
  * parent base using the target platform's environment-key semantics. A string
@@ -48,6 +54,8 @@ export function childEnv(extra?: Readonly<NodeJS.ProcessEnv>): NodeJS.ProcessEnv
 
 /** Injectable knobs so tests can exercise spill and platform behavior deterministically. */
 export interface SpawnInternals {
+  /** Node process spawner used by focused option tests. */
+  spawn?: SpawnProcess
   /** Directory for spill files (defaults to the OS temp dir). */
   spillDir?: string
   /** Windows tree-termination runner (defaults to `taskkill /PID <pid> /T /F`). */
@@ -329,6 +337,7 @@ export function spawnSubprocess(spec: SubprocessSpawnSpec, internals: SpawnInter
   }
   const spillDir = internals.spillDir ?? privateSpillDir()
   const platform = internals.platform ?? process.platform
+  const spawnProcess = internals.spawn ?? spawn
   const taskkill = internals.taskkill ?? taskkillProcessTree
   const linuxGroupHasLiveMembers = internals.linuxProcessGroupHasLiveMembers ?? linuxProcessGroupHasLiveMembers
 
@@ -347,7 +356,7 @@ export function spawnSubprocess(spec: SubprocessSpawnSpec, internals: SpawnInter
   const stdinMode = spec.stdio.stdin
 
   const env = childEnv(spec.env)
-  const child = spawn(program, args, {
+  const child = spawnProcess(program, args, {
     cwd: spec.cwd,
     env,
     stdio: [
@@ -358,6 +367,7 @@ export function spawnSubprocess(spec: SubprocessSpawnSpec, internals: SpawnInter
     // `detached` gives teardown a tree root on POSIX (its own process group);
     // Windows terminates by root pid through taskkill /T instead.
     detached: platform !== 'win32',
+    windowsHide: platform === 'win32',
   })
 
   const collectStream = (mode: SubprocessOutputMode, stream: Readable | null, label: string): OutputCollector | undefined => {

packages/subprocess/subprocess-local/tests/spawn.spec.ts

@@ -1,3 +1,4 @@
+import { spawn as nodeSpawn } from 'node:child_process'
 import { mkdtempSync, readFileSync, statSync, unlinkSync } from 'node:fs'
 import { tmpdir } from 'node:os'
 import { dirname, join } from 'node:path'
@@ -631,6 +632,30 @@ describe('stdio dispositions', () => {
 })
 
 describe('windows tree semantics (injected platform)', () => {
+  it('hides the child window without changing output, exit, stdio, or tree-root options', async () => {
+    let options: Parameters<typeof nodeSpawn>[2]
+    const result = await finish(spawnSubprocess(spec('echo hello'), {
+      spillDir,
+      platform: 'win32',
+      spawn: (program, args, spawnOptions) => {
+        options = spawnOptions
+        return nodeSpawn(program, args, spawnOptions)
+      },
+    }))
+
+    expect(options!).toMatchObject({
+      windowsHide: true,
+      detached: false,
+      stdio: ['ignore', 'pipe', 'pipe'],
+    })
+    expect(result).toMatchObject({
+      exitCode: 0,
+      signal: null,
+      stdout: { text: 'hello\n', truncated: false },
+      stderr: { text: '', truncated: false },
+    })
+  })
+
   it('host-exit termination routes through taskkill immediately', async () => {
     const killed: number[] = []
     const running = spawnSubprocess(spec('exec sleep 60', { graceMs: 60_000 }), {