`vscode-merge-base` is duplicated sometimes

[nZeus]

Type: Bug

Sometimes the vscode-merge-base setting is added multiple times for the same branch, causing other tools (Nuke) to fail. I guess there is no check here https://github.com/microsoft/vscode/blob/d9909effe9501207aae7846917a559bbcb98948c/extensions/git/src/repository.ts#L1552 if the value has already been set

VS Code version: Code 1.98.2 (Universal) (ddc367ed5c8936efe395cffeec279b04ffd7db78, 2025-03-12T13:32:45.399Z) OS version: Darwin arm64 24.3.0 Modes:

System Info

Item	Value
CPUs	Apple M2 Max (12 x 2400)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on 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 video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	26, 29, 18
Memory (System)	32.00GB (0.08GB free)
Process Argv	/Users/iliatsvetkov/Repos/workflows-2 --crash-reporter-id c0898da9-5733-479d-b3df-367da3b0a819
Screen Reader	no
VM	0%

Extensions (82)

Extension	Author (truncated)	Version
vscode-openapi	42C	4.32.2
Bookmarks	ale	13.5.0
toggle-excluded-files	amo	2.0.0
markdown-checkbox	bie	0.4.0
mermaid-markdown-syntax-highlighting	bpr	1.7.0
vscode-markdownlint	Dav	0.59.0
vscode-eslint	dba	3.0.10
githistory	don	0.6.20
xml	Dot	2.5.1
overtype	DrM	0.5.0
gitlens	eam	16.3.3
EditorConfig	Edi	0.17.2
elm-ls-vscode	elm	2.8.0
vscode-todo-plus	fab	4.19.1
dotnet-test-explorer	for	0.7.8
html-preview-vscode	geo	0.2.5
vscode-github-actions	git	0.27.1
vscode-pull-request-github	Git	0.106.0
gc-excelviewer	Gra	4.2.63
terraform	has	2.34.3
vscode-test-explorer	hbe	2.22.1
vscode-drawio	hed	1.9.0
npm-dependency-links	her	1.3.0
rest-client	hum	0.25.1
latex-workshop	Jam	10.9.0
vscode-edit-csv	jan	0.11.3
svg	joc	1.5.4
vscode-map-preview	jum	0.7.0
favorites	kdc	2.4.5
graphql-for-vscode	kum	1.15.3
contextualduplicate	laf	0.2.0
csharp-colors	log	0.2.1
tgit-cmds	mbi	1.4.2
vscode-github-actions	me-	3.0.1
rainbow-csv	mec	3.18.0
git-graph	mhu	1.30.0
prettify-json	moh	0.0.3
vscode-docker	ms-	1.29.4
blazorwasm-companion	ms-	1.1.4
csdevkit	ms-	1.17.64
csharp	ms-	2.70.15
dotnet-interactive-vscode	ms-	1.0.6177010
dotnet-maui	ms-	1.9.21
vscode-dotnet-runtime	ms-	2.3.0
vscodeintellicode-csharp	ms-	2.2.3
data-workspace-vscode	ms-	0.6.0
mssql	ms-	1.29.1
sql-bindings-vscode	ms-	0.4.0
debugpy	ms-	2025.4.1
isort	ms-	2023.10.1
python	ms-	2025.2.0
vscode-pylance	ms-	2025.3.2
jupyter	ms-	2025.2.0
jupyter-keymap	ms-	1.1.2
jupyter-renderers	ms-	1.1.0
vscode-jupyter-cell-tags	ms-	0.1.9
vscode-jupyter-slideshow	ms-	0.1.6
remote-containers	ms-	0.401.0
remote-wsl	ms-	0.88.5
hexeditor	ms-	1.11.1
powershell	ms-	2025.0.0
test-adapter-converter	ms-	0.2.1
vsliveshare	ms-	1.0.5948
vscode-paste-image	mus	1.0.4
vscode-markdown-plantuml-preview	mym	0.0.2
copy-file-name	nem	1.2.0
vetur	oct	0.37.3
vscode-versionlens	pfl	1.16.3
geo-data-viewer	Ran	2.6.0
vscode-yaml	red	1.17.0
bash-debug	rog	0.3.9
zsh-debug	rog	0.1.3
markdown-preview-enhanced	shd	0.8.18
vscode-taskexplorer	spm	2.13.2
lua	sum	3.13.9
rest-book	tan	6.2.1
pdf	tom	1.2.2
luna-paint	Tyr	0.16.0
hammerspoon	vir	0.5.2
vscode-icons	vsc	12.11.0
markdown-all-in-one	yzh	3.6.3
markdown-editor	zaa	0.1.13

(1 theme extensions excluded)

A/B Experiments

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[RigijAselo]

Is there any update regarding this issue?

[lszomoru]

@nZeus, @RigijAselo, are you able to reproduce this issue? Could you please share steps? Thanks!

[RigijAselo]

For me, it happens "randomly". Last time it happened, I did the following:

• Pulled a branch dev locally.
• Created a new branch derived-from-dev
• Pushed the new branch to origin
• I started the nuke build, got an error, and checked the config file in the .git directory.

I have done these steps multiple times, and they only happened twice.

[lszomoru]

@RigijAselo, I am pushing a change that should resolve the issue. Please let me know if you are still able to reproduce the issue after installed the VS Code Insides that will be released on Monday.

[connor4312]

@lszomoru are there any steps for this?

[blueboxes]

I am still seeing this issue. I cannot pin down how to recreate it though.

[lszomoru]

@blueboxes, what version of VS Code are you using? When you repro the issue can you please share the contents of the git output window?

[blueboxes]

I am using VS Code Insiders most of the time and a combination of command line GIT and VS code git tooling.

The issue only seems to affect NUKE, using git comands seems not to be blocked by the issue.

If I look at the config file, I see it seems to duplicate many branch entries not just one.

If I manually edit the config file in the .git folder it resolves the issue.

Its hard to spot when it first happens, just notice it next time I do a NUKE build

[blueboxes]

@lszomoru I have managed to recreate the issue !!!!

If I clone a repo and do not change the branch or interact with GIT in anyway.

Next ask Github Co-Pilot (I was in Agent mode with Claude) to make a file edit it updates the config file in the .git folder adding duplicate vscode-merge-base This happens before I click accept edits but even after accepting edits it does not fix it.

This is not an issue for using VS code; however, NUKE builds error when it gets into this state.

[lszomoru]

@blueboxes, took another look at the code and I was able to reproduce the issue locally. I have pushed a fix for the issue which should hopefully address the issue and will be available in VS Code Insiders starting next week. Having said that, please note that running git config add with the same key will result in duplicate keys so duplicate keys is something that git allows in the config file. Ideally, NUKE should also handle duplicate keys more gracefully.

[lszomoru]

@blueboxes, I was wondering if you could verify this issue. Thanks!

[blueboxes]

All looks good now thank you

[alexr00]

Also looks good to me!