How does `git mergetool` work with `git apply -3`?

General
1

I applied a patch with git apply --3way , there were conflicts, I ran git mergetool -t meld , and now I have no idea what I’m looking at.

2

When you apply a patch using git apply --3way and encounter conflicts, Git creates temporary merge files that highlight the conflicting sections. These files are usually named filename.orig , filename.local , and filename.remote .

Using git mergetool:

The git mergetool -t meld command launches a visual diff tool (Meld in this case) to help you resolve the conflicts.

Interpreting the Mergetool Interface:

The interface typically shows three panes:

  1. Original File: This shows the original version of the file before the patch was applied.
  2. Local File: This shows your current version of the file.
  3. Remote File: This shows the version of the file from the remote repository.

The conflicting sections will be highlighted, and you can manually edit the files to resolve the conflicts.

Resolving Conflicts:

  1. Review the Changes: Carefully examine the changes in each pane to understand the differences.
  2. Choose the Correct Version: Decide which version of the conflicting section is correct or if you need to combine elements from both versions.
  3. Make Changes: Edit the files directly in the mergetool interface to resolve the conflicts.
  4. Save and Close: Once you’re satisfied with the changes, save the files and close the mergetool.

Committing the Changes:

After resolving the conflicts, you can commit the changes using:

Bash

git add <filename>
git commit -m "Resolved conflicts"

Additional Tips:

  • If you’re unsure about a conflict, consider consulting with a teammate or referring to the original patch for context.
  • You can use other mergetools like diffmerge, kdiff3, or vimdiff by specifying the appropriate -t option with git mergetool .
  • If you encounter particularly complex conflicts, consider using a graphical Git client that provides a more intuitive interface for resolving them.

By following these steps and understanding the mergetool interface, you should be able to effectively resolve conflicts and continue working on your project.