A simple bash function which shows files changes since a specific commit or branch

.bash_alias

# paste this into your shell alias file
#
# Usage:
#     gitchgs  # show all files changed from develop branch
#
#     gitchgs a1b2c3d4 # show all files changed since commit a1b2c3d4
#
#     gitchgs some-branch # show all files changed between branch some-branch and HEAD
#
gitchgs () {
    # get the branch from which you want the diff
    #
    local branch=$1
    
    # is the branch null/empty? if so, subsitute the default "develop" branch
    #
    if [ -z "$branch" ]; then
        branch="develop"
    fi
    
    # show a git diff with filenames only, and showing only modified files (ie.
    # omit deleted files) between $branch and HEAD
    #
    git diff --diff-filter=ACMR --name-only $branch..HEAD

}

I use this shortcut constantly. For example, when I'm about to merge a branch with develop (I use git flow), I will run:

gitchgs | xargs atom

which will open all of the files which have changed in the feature branch in atom (my editor of choice). I then review each of the files before finishing the branch.