Git Filter Branch demo

Wanna see filter branch work?

• clone this repo
• run git blame numbers.txt and see that it is made of two commits
• run git checkout -b filter-branch-demo
• run

  git filter-branch --tree-filter "sed -i '' 's/    /  /' numbers.txt"
  

At this point you can run git blame numbers.txt and see that it is still made of two commits but their hashes have changed. And run git diff master and see that the file whitespace has been changed.

The filter-branch command steps through each commit, applies the filter (in this case the sed command), and stores the result as though that were the original commit.

References

• https://manishearth.github.io/blog/2017/03/05/understanding-git-filter-branch/
• https://git-scm.com/docs/git-filter-branch