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

An alternative to testing whether the output of git status --porcelain is empty is to test each condition you care about separately. One might not always care, for example, if there are untracked files in the output of git status.

For example, to see if there are any local unstaged changes, you can look at the return code of:

git diff --exit-code

To check if there are any changes that are staged but not committed, you can use the return code of:

git diff --cached --exit-code

Finally, if you want to know about whether there are any untracked files in your working tree that aren't ignored, you can test whether the output of the following command is empty:

git ls-files --other --exclude-standard --directory

Update: You ask below whether you can change that command to exclude the directories in the output. You can exclude empty directories by adding --no-empty-directory, but to exclude all directories in that output I think you'll have to filter the output, such as with:

git ls-files --other --exclude-standard --directory | egrep -v '/$'

The -v to egrep means to only output lines that don't match the pattern, and the pattern matches any line that ends with a /.

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).

If you are like me, you want to know if there are:

1) changes to existing files 2) newly added files 3) deleted files

and specifically do not want to know about 4) untracked files.

This should do it:

git status --untracked-files=no --porcelain

Here's my bash code to exit the script if the repo is clean. It uses the short version of the untracked files option:

[[ -z $(git status -uno --porcelain) ]] && echo "this branch is clean, no need to push..." && kill -SIGINT $$;