revert a merge code example

Example 1: undo a git merge

git reset --hard HEAD~1
git reset --hard <commit_sha>

Example 2: git revert merge

git revert -m 1 <merge-commit>

Example 3: git undo merge

git reset --hard HEAD~1

Example 4: revert last merge git

git revert -m 1 commit_hash

Example 5: undo merge

// find the commit hash
git log --oneline

git revert -m 1 [commit-hash]

// https://www.datree.io/resources/git-undo-merge