There are two projects in this solution.
GitHubProfileDefacer makes fake commits to a git repository following the pattern specified in the file "pattern.txt". The letter X is a placeholder and is ignored.
It can turn this:
XXXXXXXXXXXXXXXXXXXXX XX.XXXXXXX.X...XXXXXX XX.XXX.XXXXXXX.X.XXXX XX...X...X.X...X...XX XX.X.X.XXX.X.X.X.X.XX XX...X.XXX.X...X.X.XX XXXXXXXXXXXXXXXXXXXXX
There are other projects that can also do this, like gitfiti.
GenerateFakeCommitMessages builds fake commit messages using a Markov Model trained on real commit messages. It uses the GitHub API to pull down all commit messages for the most starred 1,000 repositories for a few different languages and then generates probable commit messages based on the Markov Model built using a given language's sample commit messages.
I wrote a blog post about generating the commit messages here. There are sample messages for different languages in the post.