After update to v3.9.1.37, “Show the diff” feature is unusable (VS 2017)

[HamRusTal]

I was using v3.9.0.0 in VS 15.9.7 (configured for C++ development) and everything worked great (thanks!).
Yesterday, VS auto-updated Git-related extensions (GitHub and GitDiffMargin), and after that whenever I open the Diff from GitDiffMargin's pop-up Actions menu, it shows as if the original file is empty and the entire text is added anew (both for C# and C++ projects). VS's built-in Diff (opened from Team Explorer - Changes) works fine as before. Uninstalling and reinstalling GitDiffMargin does not help.

[laurentkempe]

Thanks @HamRusTal to report that, I htink I just reproduced that this morning on my machine!

I will have a look asap, hopefully this evening!

[HamRusTal]

just reproduced that this morning on my machine!

Great!

I will have a look asap, hopefully this evening!

Looking forward to your findings!

P.S.
Is this screenshot from VS 2019? In VS 2017, I don't have the vertical scrollbar in the left pane. Or is it the language (C#) that makes the difference?

[laurentkempe]

Is this screenshot from VS 2019? In VS 2017, I don't have the vertical scrollbar in the left pane. Or is it the language (C#) that makes the difference?

Yeah it is VS 2019

[HamRusTal]

In the meantime, is there any API in the Visual Studio for the extension to open exactly the Git Diff window/pane which opens from “Team Explorer - Changes”?
Why:

1. It has a nicer looking tab name (e.g. “Diff - MyFile.cpp;HEAD vs. MyFile.cpp”).
2. It handles encoding properly (e.g. try diffing UTF-8-encoded file containing Chinese characters).
3. Also, I noticed that GitDiffMargin was diffing against a wrong “version” in a somewhat convoluted set-up (I'll report separately once I can reproduce it reliably).

[laurentkempe]

I identified the issue but I cannot make sense of it!
The issue is that relativepath on this line of GitCommands is of the form "path\file.cs" and the indexer is having file indexed with "path/file.cs" so changing the code to var indexEntry = repo.Index[relativePath.Replace("\\", "/")]; fix it.

What makes no sense to me is that this GitDiffMargin code didn't change since last release and looking at the code of LibGit2Sharp it is the same!
@jcansdale any idea? or @ethomson

[laurentkempe]

In the meantime, is there any API in the Visual Studio for the extension to open exactly the Git Diff window/pane which opens from “Team Explorer - Changes”?

Pls @HamRusTal open an other issue so that we do mix topics, thx

[ethomson]

LibGit2Sharp did change its behavior at some point, but I don't remember when. (Many years ago.) If you moved from a very old version to something more recent then that could indefed be the culprit.

[laurentkempe]

Thanks for the super fast answer @ethomson
I moved from v0.24.1 from Mar 12, 2018 to https://github.com/libgit2/libgit2sharp/releases/tag/v0.26 from 13 days ago!
I looked at the LibGit2Sharp code and it seems that nothing changed in that area since at least two years!

[ethomson]

Yes, I'm also surprised by this.

[HamRusTal]

open an other issue so that we do mix topics, thx

@laurentkempe Why I asked this here is because if there is such an API, it might make sense to use that instead of fixing your own implementation of the same functionality (which is not quite on par yet).

[laurentkempe]

@HamRusTal We are using the same VS API to show the diff and it is those are the same windows

See at the top the one from Changes and at the bottom the one from GitDiffMargin

1. It has a nicer looking tab name (e.g. “Diff - MyFile.cpp;HEAD vs. MyFile.cpp”).
   The name is different because we build our own caption!

2. It handles encoding properly (e.g. try diffing UTF-8-encoded file containing Chinese characters).
It is true that there is from time to time an encoding issue when used through GitDiffMargin, this I have seen myself!

3. Also, I noticed that GitDiffMargin was diffing against a wrong “version” in a somewhat convoluted set-up (I'll report separately once I can reproduce it reliably).
I am looking forward to see your issue report cause I never have seen that myself

[HamRusTal]

We are using the same VS API to show the diff and it is those are the same windows

Great! I'll file the issues separately (sooner or later).

[HamRusTal]

It works as before now, thank you!