git.rebasewhensync setting attempts a rebase when there is nothing to pull

[Shaddix]

Type: Bug

1. Use git.rebasewhensync: true.
2. Create branch 'test' from Master, commit something to branch 'test'
3. Commit something to Master
4. Switch to branch 'test'
5. Merge changes from Master to 'test' branch. Merge-commit is created
6. Press 'Sync' button. EXPECTED: changes are pushed, Merge commit is preserved ACTUAL: rebase is performed, Merge commit is not present

For me this seems like a duplicate of #149124

VS Code version: Code 1.73.1 (6261075646f055b99068d3688932416f2346dd3b, 2022-11-09T04:27:29.066Z) OS version: Windows_NT x64 10.0.22000 Modes: Sandboxed: No

System Info

|Item|Value| |---|---| |CPUs|Intel(R) Core(TM) i7-10700K CPU @ 3.80GHz (16 x 3792)| |GPU Status|2d_canvas: enabled
canvas_oop_rasterization: disabled_off
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_renderer: enabled_on
video_decode: enabled
video_encode: enabled
vulkan: disabled_off
webgl: enabled
webgl2: enabled
webgpu: disabled_off| |Load (avg)|undefined| |Memory (System)|31.82GB (6.53GB free)| |Process Argv|--crash-reporter-id 29c5a4ee-6c8e-43e6-b5dc-b3efa808b624| |Screen Reader|no| |VM|0%|

Extensions (15)

Extension|Author (truncated)|Version ---|---|--- vscode-pull-request-azdo|ank|0.0.25 vscode-css-modules|cli|0.4.2 csharpier-vscode|csh|1.3.5 vscode-eslint|dba|2.2.6 gitlens|eam|13.1.1 prettier-vscode|esb|9.10.3 dotnet|for|0.0.4 dotnet-test-explorer|for|0.7.8 vscode-scss|mrm|0.10.0 vscode-docker|ms-|1.23.1 csharp|ms-|1.25.2 playwright|ms-|1.0.1 remote-containers|ms-|0.262.3 remote-wsl|ms-|0.72.0 vscode-jest|Ort|4.6.0

A/B Experiments

``` vsliv368:30146709 vsreu685:30147344 python383:30185418 vspor879:30202332 vspor708:30202333 vspor363:30204092 vslsvsres303:30308271 pythonvspyl392:30443607 vserr242cf:30382550 pythontb:30283811 vsjup518:30340749 pythonptprofiler:30281270 vshan820:30294714 vstes263:30335439 vscoreces:30445986 pythondataviewer:30285071 vscod805cf:30301675 binariesv615:30325510 bridge0708:30335490 bridge0723:30353136 cmake_vspar411:30581797 vsaa593cf:30376535 pythonvs932:30410667 cppdebug:30492333 vsclangdc:30486549 c4g48928:30535728 dsvsc012:30540252 azure-dev_surveyone:30548225 pyindex848cf:30577861 nodejswelcome1:30587005 2e4cg342:30602488 gswce1:30612156 3d0df643:30613357 dbltrim-noruby:30604474 89544117:30613380 ```

Log of git commands when pressing 'Sync'

``` 2022-12-05 12:06:53.725 [info] > git log --oneline --cherry feature/36965-add-is-current-property...feature/36965-add-is-current-property@{upstream} -- [36ms] 2022-12-05 12:06:55.026 [info] > git ls-files --stage -- ***.ci\azure-pipelines.yml [25ms] 2022-12-05 12:06:55.055 [info] > git cat-file -s d2b5b12bec057ef5202fc2f8a8962c7b59a54d8a [27ms] 2022-12-05 12:06:55.099 [info] > git show --textconv :.ci/azure-pipelines.yml [35ms] 2022-12-05 12:06:55.308 [info] > git pull -r origin feature/36965-add-is-current-property [1579ms] 2022-12-05 12:06:55.308 [info] From https://dev.azure.com/**** * branch feature/36965-add-is-current-property -> FETCH_HEAD Rebasing (1/1) Successfully rebased and updated refs/heads/feature/36965-add-is-current-property. 2022-12-05 12:06:56.552 [info] > git ls-files --stage -- ***\.ci\azure-pipelines.yml [24ms] 2022-12-05 12:06:56.583 [info] > git cat-file -s d2b5b12bec057ef5202fc2f8a8962c7b59a54d8a [28ms] 2022-12-05 12:06:56.627 [info] > git show --textconv :.ci/azure-pipelines.yml [37ms] 2022-12-05 12:06:57.202 [info] > git push origin feature/36965-add-is-current-property:feature/36965-add-is-current-property [1891ms] 2022-12-05 12:06:57.202 [info] To https://dev.azure.com/*** 26dd442..c95e2aa feature/36965-add-is-current-property -> feature/36965-add-is-current-property ```

[ekrapfl]

I'll chime in that this is a pretty big issue. It can cause some weird issues in a scenario like so:

• I have a PR of branch feature into branch main.
• Branch main has been updated, and there are now conflicts with feature.
• I merge main into feature to resolve the conflicts (this is sometimes a simpler option than rebasing feature onto main)
• I try to sync, and VS Code ends up forcing me to resolve the conflicts again.
• It also ends up as a single commit, rather than the two (one being a merge commit) that I would have expected.
• It messes up some git PR tooling because it thinks the files from the original branch are in the PR, but they actually haven't been changed (I am referring to Azure DevOps for my example).

[lszomoru]

@Shaddix, @ekrapfl, apologies for not getting back to you on this until now. By default, when performing a rebase, git will ignore the local merge commits and drop them from the todo list as documented here. I believe that the ask here is to have the ability (probably trough a setting) to control how merge commits are being handled during a rebase operation.

[Shaddix]

yep. I just tested my situation, and saw that currently the following was run by VSCode git pull --tags -r origin vs-rebase-test If I manually run git pull --tags --rebase=merges origin vs-rebase-test then everything is ok.

So basically having a setting that controls the parameter of --rebase option would fix that for me

[ipcjs]

Set git.rebaseWhenSync to false and configure git config pull.rebase merges. This can temporarily prevent the issue.

[Shaddix]

@ipcjs but what happens in this case if I'm on develop branch, I have some local commits, and remote have some new commits as well? In this case when I press 'sync' button I'd expect a rebase, but my guess I will get a merge commit, no?

[ipcjs]

@Shaddix you will get a rebase https://git-scm.com/docs/git-pull#Documentation/git-pull.txt---rebasefalsetruemergesinteractive

[Shaddix]

thanks! gonna try