Git history for a selected file (#864)

[navn-r]

Added history context menu button in file browser

• Emits a new signal in Git Model
• Navigates to Git Panel, and switches to History Tab

Displays Single File History in History Tab

• Clicking the Discard file history button 'reverts' the history tab back to its usual repo history
• Each commit node is now hoverable, and on click will open the diff
• It will not have a hover effect and will disable its hover+click functionality if the file is binary

TODO:

• Styling: the FileItem in the history panel should be styled
• The diff file context menu item should be available for modified file
• Add/Update/Fix tests

Fixes #864

[github-actions]

👈 Launch a binder notebook on branch MLH-Fellowship/jupyterlab-git/feat/selected-file-history

[fcollonval]

Thanks a lot @navn-r This is great!

I commented in the code as much as possible. One UI comment - reusing the FileItem component to display the file name at the history top is a good idea. It will probably require some styling to highlight it compare to the history list (a different background color maybe).

[fcollonval]

Thanks for quickly applying the suggestion.

Remaining points I see:

• Styling: the FileItem in the history panel should be styled
  • to stand out of the history commit list
  • to not be hidden when the user scrolls on the commits list (maybe making it sticky would work)
  • Not applying style through the style props (see comment in code)
• The diff file context menu item should be available for modified file (it is not currently). For such case it will be good to add a history item that allow to display uncommited changes (you can have a look at how VS Code is doing it in its timeline panel).
• Correct the tests and add new ones

[navn-r]

Progress Update

From this recent push... (styled and sticky selected file + Uncommitted changes commit node)

Besides adding/fixing tests, these are the only things left, as requested by @adammclaurin:

• Handle history edge case for Ignored files

From @fcollonval:

It maybe interesting to update the current ignored files when the filebrowser path changes (hmm some polling will probably be needed too as files can be added, renamed or deleted). Maybe listening to fileChanged and pathChanged signals can be enough

• Select two arbitrary commits and view their diff (Select for compare & Compare with selected from VSCode)
• Pending discussion on how to handle this Need to separate issue+PR for this

---

Tiny Update from me:

I figured just adding a 'no history found' default to the side bar requires less effort yet delivers the same end-user value, compared to watching for the ignored files then trying to hide the history context button.

[fcollonval]

Thanks for the update.

Select two arbitrary commits and view their diff (Select for compare & Compare with selected from VSCode)

I would left this one out for a follow-up PR. This brings in already a big change.

For how to do it (in the single file history view), using a context menu would be nice and/or a visual check box on the commit info top right - but this maybe complex because we need to enforce two nodes selection only and there is the notion of what are the reference and challenger.

[fcollonval]

I figured just adding a 'no history found' default to the side bar requires less effort yet delivers the same end-user value, compared to watching for the ignored files then trying to hide the history context button.

👍

We can open a new issue with enhancement proposal to deal with ignored files.

[fcollonval]

Almost there @navn-r

I have some suggestions to improve readability. You need also to rebase the PR and to fix the tests.

I opened the follow-up issues: #984 and #985

[fcollonval]

Thanks @navn-r

Could you please add a Python unit test that check the git command executed and the parsing of the output?

The best starting point for that would be to duplicate jupyterlab_git/tests/test_detailed_log.py and apply it to the single file case.

[fcollonval]

Thanks a lot @navn-r

[krassowski]

Translation missing?

[fcollonval]

Thanks @krassowski