From 96ba61f7e69035fefd044caa7a674ddd06eaa043 Mon Sep 17 00:00:00 2001
From: Neil <4138956+nwparker@users.noreply.github.com>
Date: Sat, 5 Sep 2026 17:50:48 -0700
Subject: [PATCH] Preserve preparation ownership until Git removal starts

---
 ...rktree-create-preparation-real-git.test.ts | 33 +++++++++++++++++++
 src/main/git/worktree-create-preparation.ts   | 18 +++++-----
 src/shared/git-binary-compatibility.test.ts   | 10 ++++++
 3 files changed, 52 insertions(+), 9 deletions(-)

diff --git a/src/main/git/worktree-create-preparation-real-git.test.ts b/src/main/git/worktree-create-preparation-real-git.test.ts
index c281c6d637e..5dac51c5fcd 100644
--- a/src/main/git/worktree-create-preparation-real-git.test.ts
+++ b/src/main/git/worktree-create-preparation-real-git.test.ts
@@ -55,6 +55,39 @@ afterEach(async () => {
 })
 
 describe('prepared worktree creation with real Git', () => {
+  it('retains preparation ownership when the removal command cannot start', async () => {
+    const fixture = await createRepo()
+    const repoPath = await realpath(fixture.repoPath)
+    const root = await realpath(fixture.root)
+    const preparedPath = join(root, WORKTREE_CREATE_PREPARATION_DIRECTORY, 'owned-removal')
+    await mkdir(join(root, WORKTREE_CREATE_PREPARATION_DIRECTORY), { recursive: true })
+    const lockReason = createWorktreePreparationLockReason('removal-failure')
+    await prepareWorktreeCreateCheckout(repoPath, preparedPath, 'main', lockReason)
+    const original = gitRunner.gitExecFileAsync
+    const spy = vi.spyOn(gitRunner, 'gitExecFileAsync').mockImplementation((args, options) => {
+      if (args.includes('remove') && args.includes(preparedPath)) {
+        return Promise.reject(new Error('injected removal launch failure'))
+      }
+      return original(args, options)
+    })
+    try {
+      await expect(discardPreparedWorktree(repoPath, preparedPath)).rejects.toThrow(
+        'injected removal launch failure'
+      )
+      const remaining = await listWorktrees(repoPath, { includeCreatePreparations: true })
+      const prepared = remaining.find((worktree) =>
+        areWorktreePathsEqual(worktree.path, preparedPath)
+      )
+      expect(prepared).toBeDefined()
+      expect(prepared?.lockReason).toBe(lockReason)
+      expect(await readFile(join(preparedPath, 'version.txt'), 'utf8')).toBe('one\n')
+    } finally {
+      spy.mockRestore()
+      await discardPreparedWorktree(repoPath, preparedPath)
+    }
+    expect(existsSync(preparedPath)).toBe(false)
+  })
+
   it('creates and finalizes while dead-owner reclamation is stalled', async () => {
     const fixture = await createRepo()
     const repoPath = await realpath(fixture.repoPath)
diff --git a/src/main/git/worktree-create-preparation.ts b/src/main/git/worktree-create-preparation.ts
index 78713957690..0f27f045287 100644
--- a/src/main/git/worktree-create-preparation.ts
+++ b/src/main/git/worktree-create-preparation.ts
@@ -45,16 +45,16 @@ async function performDiscardPreparedWorktree(
     timeout: options.timeout ?? WORKTREE_REMOVAL_REGISTRATION_TIMEOUT_MS
   }
   try {
+    // Preserve the ownership lock if removal cannot start; Git 2.25 supports locked removal.
     await gitExecFileAsync(
-      [...windowsLongPathGitArgs(repoPath), 'worktree', 'unlock', worktreePath],
-      cleanupGitOptions
-    )
-  } catch {
-    // It may be unlocked already or only partially registered.
-  }
-  try {
-    await gitExecFileAsync(
-      [...windowsLongPathGitArgs(repoPath), 'worktree', 'remove', '--force', worktreePath],
+      [
+        ...windowsLongPathGitArgs(repoPath),
+        'worktree',
+        'remove',
+        '--force',
+        '--force',
+        worktreePath
+      ],
       cleanupGitOptions
     )
   } finally {
diff --git a/src/shared/git-binary-compatibility.test.ts b/src/shared/git-binary-compatibility.test.ts
index fb8161b9f90..e11fa6ed2c4 100644
--- a/src/shared/git-binary-compatibility.test.ts
+++ b/src/shared/git-binary-compatibility.test.ts
@@ -204,6 +204,16 @@ describeBinaryCompatibility('real Git binary compatibility', () => {
     await rm(join(repoPath, 'deferred-trash'), { recursive: true, force: true })
   })
 
+  it('removes locked prepared worktrees without a separate unlock', async () => {
+    await runGit(['worktree', 'add', '--detach', '--no-checkout', 'compat-discard', 'HEAD'])
+    await runGit(['-C', 'compat-discard', 'reset', '--hard', 'HEAD'])
+    await runGit(['worktree', 'lock', '--reason', 'owned preparation', 'compat-discard'])
+    await runGit(['worktree', 'remove', '--force', '--force', 'compat-discard'])
+    expect((await runGit(['worktree', 'list', '--porcelain'])).stdout).not.toContain(
+      'compat-discard'
+    )
+  })
+
   it('supports prepared worktree creation and finalization', async () => {
     await runGit(['worktree', 'add', '--detach', '--no-checkout', 'compat-prepared', 'HEAD'])
     await runGit(['-C', 'compat-prepared', 'reset', '--hard', 'HEAD'])