git rev-list

List revisions (commits) in reverse chronological order. More information: https://git-scm.com/docs/git-rev-list.

git rev-list HEAD

git rev-list -n 1 HEAD -- path/to/file

git rev-list --since='2019-12-01 00:00:00' branch_name

git rev-list --merges commit

git rev-list tag_name..HEAD --count