Also works in .zshrc

.bashrc

# Start working on a pull request, this requires a .git/user-repo file
# containing the string "user/repository"
pr () {
    if [[ ! -r .git/user-repo ]]; then
        echo "Need to setup user/repo" >&2
        return 1
    fi
    local user_repo=$(< .git/user-repo)
    local pr_num=$1
    if [[ -z $pr_num ]]; then
        echo "Need the pull request number" >&2
        return 1
    fi
    local branch=merge-pr-$pr_num
    if [[ -e .git/refs/heads/$branch ]]; then
        echo "Already working on pull request $pr_num, delete branch '$branch' and try again" >&2
        return 1
    fi
    (
    set -e
    local user_repo=$(< .git/user-repo)
    git checkout -b $branch
    curl "https://github.com/$(< .git/user-repo)/pull/$pr_num.patch" 2> /dev/null | git am --3way
    )
}

# Finish working on a pull request, besides the .git/user-repo file,
# this requires a .git/ghtok file containing the oauth token for accessing the
# repository
mpr () {
    if [[ ! -r .git/user-repo ]]; then
        echo "Need to setup user/repo" >&2
        return 1
    fi
    local user_repo=$(< .git/user-repo)

    local ghtok=
    if [[ -r .git/ghtok ]]; then
        ghtok=$(< .git/ghtok)
    elif [[ -n "$GITHUB_TOKEN" ]]; then
        echo "Couldn't find github token at .git/ghtok, using env \
            variable GITHUB_TOKEN" >&2
        ghtok="$GITHUB_TOKEN"
    else
        echo "Couldn't find neither .git/ghtok nor GITHUB_TOKEN, exiting" >&2
        return 1
    fi

    local pr_num=$1
    if [[ -z $pr_num ]]; then
        echo "Need the pull request number" >&2
        return 1
    fi

    local branch=merge-pr-$pr_num
    if [[ ! -e .git/refs/heads/$branch ]]; then
        echo "Not working on $pr_num" >&2
        return 1
    fi
    (
    set -e
    echo "Will push commits and comment/close on PR $pr_num"
    git checkout master
    echo "Retrieving the PR title..."
    local sed="sed"
    if [[ `uname` == 'Darwin' ]]; then
        export sed="gsed"
    fi

    # check if this is a prefixed PR ([RFC], [WIP], ...)
    local pr_meta="$(curl https://api.github.com/repos/$user_repo/issues/$pr_num 2> /dev/null)"
    local pr_title=
    if egrep -q '^\[\w+\]' <<< $pr_meta; then
        local pr_title="$($sed -n -e 's/.*"title":\s\+"\([^"]\+\)".*/\1/g' -e 's/^\[\(\w\+\)]\s*\(.\+\)/\2/p' <<< $pr_meta)"
    else
        local pr_title="$($sed -n -e 's/.*"title":\s\+"\([^"]\+\)".*/\1/p' <<< $pr_meta)"
    fi

    git merge --no-ff -m "Merge pull request #$pr_num '$pr_title'" $branch
    git branch -D $branch
    git log --graph --decorate --pretty=oneline --abbrev-commit --all --max-count=20
    echo "Continue with the merge?[y/N]"
    local confirm
    read confirm
    if [[ $confirm != "y" ]]; then
        echo "Merge cancelled" >&2
        git reset --hard HEAD~1
        exit 1
    fi
    git push
    curl \
        -X POST \
        -H "Authorization: token $ghtok"  \
        -d '{"body": ":+1: merged, thanks"}' \
        "https://api.github.com/repos/$user_repo/issues/$pr_num/comments" > /dev/null
    curl \
        -X PATCH \
        -H "Authorization: token $ghtok"  \
        -d '{"state": "closed"}' \
        "https://api.github.com/repos/$user_repo/issues/$pr_num" > /dev/null
    echo "Done"
    )
}