git-pullme

#!/bin/bash
#
# This will fetch and merge only the branch you're currently in, avoiding
# fetches that you aren't interested in and possibly avoiding "non-fast-forward"
# messages on pushes
#

function usage() {
    echo "Usage: git pullme [-r | --no-rebase]" >&2
}

# Default is that we will allow a rebase
rebase_ok=yes

GETOPT=$(getopt -u -o hr --long no-rebase -- "$@")
if [[ $? != 0 ]]; then
    usage
    exit 1
fi
set -- $GETOPT

while [[ 0 != $# ]]; do
    case "$1" in
        -r|--no-rebase)
            rebase_ok=no
            ;;
        -h)
            usage
            exit 0
            ;;
        --)
            shift
            break
            ;;
        *)
            echo "Unrecognized option ($1)??" >&2
            usage
            exit 1
            ;;
    esac
    shift
done

ref=$(git symbolic-ref HEAD 2>/dev/null)
branch=${ref##refs/heads/}

if [[ -z $branch ]]; then
    echo "Not on any branch that I can find!"
    exit 1
fi

remote=$(git config --get "branch.$branch.remote")
merge_ref=$(git config --get "branch.$branch.merge")
merge=${merge_ref##refs/heads/}

if [[ -z $remote || -z $merge ]]; then
    echo 'Your branch is not tracking a remote branch.  Consider using "git corb"'
    exit 1
fi

echo "] git fetch $remote $merge:refs/remotes/$remote/$merge"
git fetch $remote $merge:refs/remotes/$remote/$merge
echo

behind=$(git rev-list "$branch..$remote/$merge" 2>/dev/null | wc -l)
ahead=$(git rev-list "$remote/$merge..$branch" 2>/dev/null | wc -l)
local_merges=$(git rev-list --parents "$remote/$merge..$branch" | awk 'NF > 2 {print}' | wc -l)

# If we are behind the remote, we'll need to merge
if [[ $behind -gt 0 ]]; then
    # If we are ahead of the remote, it's a diverge
    if [[ $ahead -gt 0 ]]; then
        # If our changes contain no merges, and we are allowed to rebase, we will do that,
        # avoiding superfluous merges
        if [[ $rebase_ok = yes && $local_merges = 0 ]]; then
            echo "Your local commits do not contain any merges, rebasing on $remote/$merge"
            echo "] git rebase $remote/$merge"
            git rebase "$remote/$merge"
        # Otherwise, we must merge
        else
            echo "] git merge $remote/$merge"
            git merge "$remote/$merge"
        fi
    # We're behind only, do a merge
    else
        echo "] git merge $remote/$merge"
        git merge "$remote/$merge"
    fi
else
    echo "Already up-to-date."
fi