Following on my last entry, where I built a better pre-commit hook to ensure every commit in my Git history passed make check with flying colors, I realized something today about my good friend, rebase .

…If I have a set of ten commits, and realize the 3rd commit has an oversight I’d like to smooth out, I can make a new commit to fix the problem and then merge it with that old commit, resulting in a nice, clean set of commits for pushing.

…A rewritten commit is really a new commit , which means it hasn’t been tested, may never have existed as a working tree, and certainly isn’t the same as the previous commit, however similar its diff output may be.

… Thus the only way I could use rebase in confidence would be to run the same pre-commit again on every changed commit during the rebase operation — which is something Git doesn’t do.