command to squash up to last 3 commits into a single commit code example

Example 1: squash commit history git

# THIS TURNS YOUR WHOLE COMMIT HISTORY INTO ONE SINGLE COMMIT!
# BE CAREFUL!

git rebase --root -i

# In your editor, for each commit except the top, change `pick` to `squash`

Example 2: squash 3 commit

$ git rebase -i HEAD~3