Checking the exit code of git diff

git diff-index --quiet HEAD || git commit -m 'bla'

Not produce the correct result if there are differences only between the index and work tree.

Improve Answer:

git diff-index --quiet --cached HEAD || git commit -m 'bla'

Other solution:

git commit -m 'bla' --allow-empty

Not good enough, it would actually create a commit though.

Reference:

• https://stackoverflow.com/questions/8123674/how-to-git-commit-nothing-without-an-error
• https://coderwall.com/p/vkdekq/git-commit-allow-empty