How can I fetch an unmerged pull request for a branch I don't own?

Question

I need to pull in a specific pull request (that hasn\'t been processed into the main stream yet) in the NServiceBus repo:

https://github.com/johnsimons/NServiceBus/c

Answer 1

You can do this:

1) Add the upstream remote:

git remote add upstream git@github.com:Particular/NServiceBus.git

2) After that, you can checkout any pull request to a new branch per its ID:

git fetch upstream pull/PULL_REQUEST_ID/head:NEW_BRANCH_NAME

Then you'll have a branch named NEW_BRANCH_NAME containing the PR code.

Adding an alias:

If you do this as often as me, you may want to setup some aliases for it. I have this in my .gitconfig:

[alias]
    fetch-pr = "!f(){\
        [ -z \"$1\" ] && { echo Usage: git fetch-pr PULL_REQUEST_ID [REMOTE_NAME] [NEW_BRANCH_NAME]; exit 1; }; \
        remote=${2:-origin}; \
        branch=${3:-pr-$1}; \
        git fetch $remote \"pull/$1/head:$branch\"; \
        }; f "
    pr = "!f(){\
        branch=${3:-pr-$1}; \
        git fetch-pr \"$@\"; \
        git switch $branch; \
        }; f "

With the above, I can do:

git fetch-pr 123              # fetch PR #123 into branch pr-123
git fetch-pr 123 some-branch  # fetch PR #123 into some-branch
git pr 123                    # fetch and switch to the branch