git merge-base

Find a common ancestor of two commits. More information: https://git-scm.com/docs/git-merge-base.

• Print the best common ancestor of two commits:

git merge-base commit_1 commit_2

• Print all best common ancestors of two commits:

git merge-base --all commit_1 commit_2

• Check if a commit is an ancestor of a specific commit:

git merge-base --is-ancestor ancestor_commit commit