test(git): verify native Windows exited-child termination guard

.github/workflows/git-command-termination-runtime.yml

@@ -0,0 +1,22 @@
+name: Git command termination runtime
+on:
+  pull_request:
+    paths:
+      - 'src/main/git/command-runner/spawned-command-tree-kill*'
+      - '.github/workflows/git-command-termination-runtime.yml'
+  workflow_dispatch:
+permissions:
+  contents: read
+jobs:
+  windows-exit:
+    runs-on: windows-latest
+    timeout-minutes: 20
+    env:
+      ORCA_BACKGROUND_LAUNCH: '1'
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          persist-credentials: false
+      - uses: ./.github/actions/install-node-dependencies
+      - name: Verify exited native child does not trigger taskkill
+        run: node node_modules/vitest/vitest.mjs run --config config/vitest.config.ts src/main/git/command-runner/spawned-command-tree-kill.test.ts

src/main/git/command-runner/spawned-command-tree-kill.test.ts

@@ -1,4 +1,6 @@
 import { ChildProcess } from 'node:child_process'
+import { once } from 'node:events'
+import { spawnProcess } from '../../../shared/child-process/run-process'
 import type * as NodeChildProcess from 'node:child_process'
 import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 
@@ -92,4 +94,29 @@ describe('Git command tree termination', () => {
     expect(child.kill).toHaveBeenCalledOnce()
     expect(spawnMock).not.toHaveBeenCalled()
   })
+  it.skipIf(originalPlatform !== 'win32').each([0, 128])(
+    'does not taskkill an actual native Windows child after exit %i',
+    async (exitCode) => {
+      const original = await vi.importActual<typeof NodeChildProcess>('node:child_process')
+      spawnMock.mockImplementation((program, args, options) => {
+        if (program !== process.execPath) {
+          throw new Error('Unexpected external process in native exit probe')
+        }
+        return original.spawn(program, args, options)
+      })
+      const child = spawnProcess({
+        program: process.execPath,
+        args: ['-e', `process.exit(${exitCode})`]
+      })
+      const closed = once(child, 'close')
+      await once(child, 'exit')
+      expect(child.exitCode).toBe(exitCode)
+      expect(child.pid).toBeGreaterThan(0)
+      spawnMock.mockClear()
+      await killSpawnedCommandTree(child)
+      expect(spawnMock).not.toHaveBeenCalled()
+      expect(admitMock).not.toHaveBeenCalled()
+      await closed
+    }
+  )
 })