Pulls in updates from the remote tracking branch of the specified branch (defaults to current branch), rebasing them on top of the current branch and preserving merge commits.

git-up.sh

#!/bin/bash
set -e
orig_head=$(git rp HEAD)
branch=${1:-$(git rev-parse --abbrev-ref HEAD)}
remote=$(git config "branch.$branch.remote")
tracking_branch=$(git rev-parse --abbrev-ref --symbolic-full-name $branch@{u})

git fetch $remote
git rebase --preserve-merges $tracking_branch

if [ "$orig_head" == $(git rp HEAD) ]; then
    echo No update
else
    echo
    git clog $orig_head..$tracking_branch
    echo
fi