Rebase from worktree window operates on wrong worktree and wrong branch, causing data loss

[jvillemure]

Type: Bug

Summary

When performing a rebase via VS Code's Source Control UI from a worktree window, three
things went wrong:

1. Wrong branch rebased: I checked out feature/refactoring and asked to rebase it
   onto feature/container-phase0. Instead, VS Code rebased feature/A (a different branch)
   onto feature/container-phase0. In a normal git rebase, the currently checked-out branch
   is the one that gets rebased — VS Code ignored the checked-out branch and rebased the
   worktree's prior branch instead.

2. Operations dispatched to wrong worktrees: Instead of confining all git operations to
   the worktree where I initiated the rebase, VS Code ran checkout, reset, and rebase
   across three different worktrees.

3. Uncommitted changes destroyed: A git reset HEAD was executed in an unrelated
   worktree that had uncommitted work, permanently destroying those changes.

Setup

A single repository with multiple worktrees:

~/repo/                     → main checkout, on branch `development` (had uncommitted changes)
~/repo.worktrees/wt-A/      → worktree on branch `feature/A`
~/repo.worktrees/wt-B/      → worktree on branch `issue/B` (had uncommitted changes)
~/repo.worktrees/wt-C/      → worktree on branch `other-edits`

I had two VS Code windows open:

1. The main repo (~/repo/) on branch development — had uncommitted changes
2. Worktree wt-A (~/repo.worktrees/wt-A/) on branch feature/A

From the wt-A window, I checked out branch feature/refactoring and asked VS Code to
rebase it on top of feature/container-phase0.

What I expected

A standard git rebase feature/container-phase0 while feature/refactoring is checked out:

• The currently checked-out branch (feature/refactoring) gets rebased onto
  feature/container-phase0
• All operations happen within wt-A only
• No other worktree is touched

What actually happened (reconstructed from git reflog)

VS Code did not rebase the checked-out branch. Instead, it scattered operations across
three worktrees and rebased a completely different branch:

Main repo (~/repo/) — should NOT have been touched

Time	Reflog entry
16:24:24	checkout: moving from development to feature/container-phase0
16:25:45	checkout: moving from feature/container-phase0 to development

The main repo HEAD was moved to feature/container-phase0 and back. Any uncommitted
changes that conflicted with this checkout would have been silently dropped.

Worktree wt-A (~/repo.worktrees/wt-A/) — where I initiated the rebase

Time	Reflog entry
16:27:36	checkout: moving from feature/A to feature/container-phase0
16:27:51	pull --autostash origin feature/container-phase0: Fast-forward
16:28:15	checkout: moving from feature/container-phase0 to feature/A
16:30:24	rebase (start): checkout feature/container-phase0
16:30:25	rebase (pick): …
16:30:25	rebase (finish): returning to refs/heads/feature/A

The rebase landed on feature/A — but I had checked out feature/refactoring and
wanted to rebase that branch. VS Code rebased the worktree's prior branch instead of
the branch I actually had checked out. From the rebase's perspective, the "incoming"
commits were picked from the wrong branch entirely.

Worktree wt-B (~/repo.worktrees/wt-B/) — completely unrelated, had uncommitted work

Time	Reflog entry
16:29:27	reset: moving to HEAD ← this destroyed my uncommitted changes
16:29:28	checkout: moving from issue/B to feature/refactoring
16:32:44	checkout: moving from feature/refactoring to issue/B

VS Code ran git reset HEAD and git checkout feature/refactoring in wt-B — a worktree
I was not interacting with at all. The reset: moving to HEAD discarded all uncommitted
modifications in that worktree. It appears VS Code intended to check out feature/refactoring
here rather than rebase it — as if the "rebase" operation was decomposed into a checkout in
one worktree and a rebase in another, with the checkout targeting an arbitrary worktree and
the rebase targeting the wrong branch.

Impact

• Uncommitted changes in wt-B were permanently destroyed (partially recovered via
  VS Code's local Timeline feature, but only up to the last save — any unsaved
  edits between saves were lost)
• The rebase was applied to the wrong branch (feature/A instead of feature/refactoring)
• The main repo HEAD was unexpectedly moved
• The entire operation should have been scoped to a single worktree

Expected behavior

1. A rebase should operate on the currently checked-out branch, consistent with
   how git rebase works on the command line
2. All git operations triggered from a worktree VS Code window should execute exclusively
   within that worktree
3. If VS Code must touch another worktree for any reason, it should detect uncommitted
   changes and refuse/warn before proceeding, or at minimum stash them

Related issues

• If multiple instances of VSCode are opened for different git worktrees, the git editor is opened in the main worktree VSCode instance #290708 — git editor opens in main worktree instead of active worktree (same root cause:
  operations dispatched to wrong worktree)
• git commit with git config core.editor = code --wait opens in window for main git worktree instead of active window #299540 — git commit with core.editor = code --wait opens in wrong window
• After resolving all conflicts during a rebase, continue the rebase #249596 — rebase continuation broken in worktrees
• Git - Support git worktrees in workspace #68038 — original worktree support tracking issue

VS Code version: Code 1.112.0 (07ff9d6, 2026-03-17T18:09:23Z)
OS version: Windows_NT x64 10.0.26200
Modes:
Remote OS version: Linux x64 6.6.87.2-microsoft-standard-WSL2
Remote OS version: Linux x64 6.6.87.2-microsoft-standard-WSL2
Remote OS version: Linux x64 6.6.87.2-microsoft-standard-WSL2
Remote OS version: Linux x64 6.6.87.2-microsoft-standard-WSL2

System Info

Item	Value
CPUs	13th Gen Intel(R) Core(TM) i7-13850HX (28 x 2304)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x10de, DEVICE=0x27bb [NVIDIA RTX 3500 Ada Generation Laptop GPU], DRIVER_VENDOR=NVIDIA, DRIVER_VERSION=32.0.15.8195 ACTIVE GPU1: VENDOR= 0x8086, DEVICE=0xa788 [Intel(R) UHD Graphics], DRIVER_VERSION=32.0.101.7080 GPU2: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.7309 Machine model name: Machine model version: direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off trees_in_viz: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	31.69GB (8.09GB free)
Process Argv	--crash-reporter-id 0ee9c5df-6520-4de7-8875-9c23c4ea84c3
Screen Reader	no
VM	0%

Item	Value
Remote	WSL: Ubuntu
OS	Linux x64 6.6.87.2-microsoft-standard-WSL2
CPUs	13th Gen Intel(R) Core(TM) i7-13850HX (28 x 0)
Memory (System)	15.46GB (8.15GB free)
VM	0%

Item	Value
Remote	WSL: Ubuntu
OS	Linux x64 6.6.87.2-microsoft-standard-WSL2
CPUs	13th Gen Intel(R) Core(TM) i7-13850HX (28 x 0)
Memory (System)	15.46GB (8.16GB free)
VM	0%

Item	Value
Remote	WSL: Ubuntu
OS	Linux x64 6.6.87.2-microsoft-standard-WSL2
CPUs	13th Gen Intel(R) Core(TM) i7-13850HX (28 x 0)
Memory (System)	15.46GB (8.15GB free)
VM	0%

Item	Value
Remote	WSL: Ubuntu
OS	Linux x64 6.6.87.2-microsoft-standard-WSL2
CPUs	13th Gen Intel(R) Core(TM) i7-13850HX (28 x 0)
Memory (System)	15.46GB (8.15GB free)
VM	0%

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