Bulk resolve merge conflicts

Problem

You have a branch that conflicts with master in small but numerous occasions. Manually fixing each would be repetitive. Even running git checkout --theirs -- [filename] on each would be repetitive.

Solution

We need several things here:

1. A way to get a list of all conflicted files

2. A way to interactively filter out the files we don't want (it's unlikely you know exactly which files have trivial diffs beforehand)

3. xargs to pass these into git rebase

A naive approach would be to use the output of git diff. We use the --no-pager option to cat the output for use in pipes.

git --no-pager diff --name-only | fzf | xargs git checkout --theirs --

However, this does not distinguish between regular diffs and conflicts.

Looking at the docs, it seems like adding the --check flag to git diff does what we want. However, --check also flags whitespace markers for some reason, which can add noise, and it adds text after the filename, which must be split out (and I'm bad at awk).

The --diff-filter option is more promising. With --diff-filter=U, we only list unmerged files, and when rebasing, only conflicts are shown.

So, our final solution is:

git --no-pager diff --name-only --diff-filter=U | fzf | xargs git checkout --theirs --

Facebook Pathpicker

There's an interesting file picker tool from Facebook called PathPicker. Rather than operating on lines grep-like tools, fpp parses input and extracts path-like entities. This doesn't filter out non-conflicted diffs, but at least the filenames will be visually organized and sectioned like they are from git status. Thus, our command becomes:

git status | fpp

This approach relies more heavily on a UI, but is simpler.

The nuclear approach

When you are sure that all conflicts are trivial, there is a blunter, simpler solution:

git rebase --abort
git rebase -Xtheirs origin/master

Bonus tip

While figuring this out, I also stumbled across git checkout --conflict, which resets merge conflict markers in case you made a mistake and want to start the resolution from scratch.