git - How to force a merge to succeed when there are conflicts?

Question

I'm trying to merge a pull request that has one conflict in one file (see below). The instructions for merging the pull request are provided by github are as follows. Its important to to perform this merge so the person submitting the pr gets credit for it.

# Step 1: From your project repository, check out a new branch and test the changes.
git checkout -b droark-master master
git pull https://github.com/droark/cryptopp.git master

# Step 2: Merge the changes and update on GitHub.
git checkout master
git merge --no-ff droark-master
git push origin master

I know how to fix the one line in the one conflicting file. What I don't know how to do is make Git perform the merge and stop complaining about broken index files.

How do I make Git perform the merge, ensure the person who provided the pull request gets credit for it, and stop breaking index files?

---

I tried to repair the merge with Git merge errors. One set of errors turns into another set of errors, ad infinitum. I also tried resetting the problem file according to Ignore files during merge with plans to copy/paste the one line needed, but the broken index persists.

This has turned into a complete waste of time, and I am no longer interested in trying to do it Git's way since it wastes so much time. Now I simply want Git to perform the merge and stop breaking index files.

---

Here is the output produced when merging using github's instructions:

$ git pull https://github.com/droark/cryptopp.git master
From https://github.com/droark/cryptopp
 * branch            master     -> FETCH_HEAD
Auto-merging validate.h
Auto-merging validat2.cpp
Auto-merging validat1.cpp
Auto-merging test.cpp
CONFLICT (content): Merge conflict in test.cpp
Auto-merging pubkey.h
Automatic merge failed; fix conflicts and then commit the result.

Answer 1

There's no way to merge without resolving conflicts. Otherwise, how would git know what to merge? You can, however, checkout the version from either branch you're merging using git checkout --ours <filepath> or git checkout --theirs <filepath>. Here's an example:

Suppose you're on the master branch merging in staging:

git checkout master
git merge staging

And git shows a bunch of conflicts:

...
CONFLICT: Readme.md
...

If you want to keep the version of Readme.md that's on master, then you would run:

git checkout --ours Readme.md

Note that since you're on master --ours refers to "this" branch, i.e. master.

Now, you can simply add it to the index to mark it as resolved:

git add Readme.md

This effectively ignores any changes to Readme.md on the staging branch.

You can repeat this process for each file you want to omit from the merge. When you're done, commit as you normally would:

git commit -m "whatever..."

In order to repeat it for all files with conflicts you can do

for f in $(git diff --name-only --diff-filter=U | cat); do
   echo "Resolve conflict in $f ..."
   git checkout --theirs $f
done