blame navigation to in-line git diff for current block

[drdozer]

I am trying to resolve a complex regression in a fork of a github project. I have the blame info displayed in the gutter, and I can see a block of blame from the same commit next to a block of code that looks fishy. But I can't display the code from that blame side-by-side with the current code. I can navigate to a diff for the whole patch but that's huge, and covers many files. I just want to see the difference between my code in the current on-disk version and the code from that commit for that block, or for all blocks in this file if that's easier.

[drdozer]

It may be essentially the same feature, or perhaps not, but it would be useful to be able to in the editor (but not on disk) roll back a block or a tab through the git history. So imagine a workflow where

• there is a bug
• I identify a suspicious line
• I display the blame info, and see a block that line sits in
• clicking on the blame gives me the option to display a diff to the right for this block
• the diff has a widget that lets me scroll through the commit history for that block
• the live text also gets a widget so I can add a new column for a new history diff, so I can compare multiple git versions against my live code
• none of this alters the text on disk -- the source is only changed if I edit the text for the local code
• I can pull lines or highlighted blocks from the diff displays back into my live code to back-patch it

I can't find any functionality like this in other editors e.g. vscode.

[drdozer]

VS Code has a git history tab that lets you see diffs between different git commits for a file, but it doesn't have any editing support -- you can't take that diff and then fold this into the version that you are currently editing. The diff view isn't accessible via the blame UX in VS Code.