How to check if there's nothing to be committed in the current branch?

Question

The goal is to get an unambiguous status that can be evaluated in a shell command.

I tried git status but it always returns 0, even if there are items

Answer 1

Not pretty, but works:

git status | grep -qF 'working directory clean' || echo "DIRTY"

Not sure whether the message is locale dependent, so maybe put a LANG=C in front.

Answer 2

The return value of git status just tells you the exit code of git status, not if there are any modifications to be committed.

If you want a more computer-readable version of the git status output, try

git status --porcelain

See the description of git status for more information about that.

Sample use (script simply tests if git status --porcelain gives any output, no parsing needed):

if [ -n "$(git status --porcelain)" ]; then
  echo "there are changes";
else
  echo "no changes";
fi

Please note that you have to quote the string to test, i.e. the output of git status --porcelain. For more hints about test constructs, refer to the Advanced Bash Scripting Guide (Section string comparison).

Answer 3

From the git source code there is a sh script which includes the following.

require_clean_work_tree () {
    git rev-parse --verify HEAD >/dev/null || exit 1
    git update-index -q --ignore-submodules --refresh
    err=0

    if ! git diff-files --quiet --ignore-submodules
    then
        echo >&2 "Cannot $1: You have unstaged changes."
        err=1
    fi

    if ! git diff-index --cached --quiet --ignore-submodules HEAD --
    then
        if [ $err = 0 ]
        then
            echo >&2 "Cannot $1: Your index contains uncommitted changes."
        else
            echo >&2 "Additionally, your index contains uncommitted changes."
        fi
        err=1
    fi

    if [ $err = 1 ]
    then
        test -n "$2" && echo >&2 "$2"
        exit 1
    fi
}

This sniplet shows how its possible to use git diff-files and git diff-index to find out if there are any changes to previously known files. It does not however allow you to find out if a new unknown file has been added to the working tree.