git-undo

Remove the most recent commit

$ git undo

$ git undo [3]

git undo [commit-ish]
git undo [--hard | --soft | --mixed]

commit-ish
    Optional. When used without --hard, --soft, or --mixed options, this specifies the commit to revert. It can be a commit hash, a branch name, or a relative reference like HEAD~1. If omitted, git undo defaults to reverting the last commit (HEAD).

--hard
    Optional. When specified, performs a destructive undo by resetting the branch to the commit immediately preceding HEAD (HEAD~1), equivalent to git reset --hard HEAD~1. This permanently discards all uncommitted changes in the working directory and staging area. This option is mutually exclusive with commit-ish.

--soft
    Optional. When specified, performs an undo by resetting the branch to HEAD~1, equivalent to git reset --soft HEAD~1. This moves the branch pointer but keeps the changes that were in the undone commit(s) in the staging area (index). This option is mutually exclusive with commit-ish.

--mixed
    Optional. When specified, performs an undo by resetting the branch to HEAD~1, equivalent to git reset --mixed HEAD~1. This is the default behavior for git reset. It moves the branch pointer and keeps the changes from the undone commit(s) in the working directory as unstaged changes. This option is mutually exclusive with commit-ish.

git-undo is a convenience command, often provided by third-party Git utility collections like git-extras, designed to simplify common "undo" operations in a Git repository. It typically acts as a wrapper around more fundamental Git commands such as git revert and git reset. By default, when invoked without specific options, it often performs a non-destructive undo, similar to git revert HEAD, creating a new commit that reverses the changes of the last commit. However, it also provides options, such as --hard, --soft, or --mixed, to invoke git reset for more aggressive undo actions, allowing users to move the branch pointer and discard changes in the working directory or staging area. Its primary purpose is to abstract away the complexity of choosing the correct underlying Git command for various undo scenarios, making it quicker and easier for users to revert or reset their repository state.

git-undo is not a standard command included with Git; it typically needs to be installed as part of a third-party package like git-extras or implemented as a custom shell alias/script.
The --hard option is destructive: it will permanently discard uncommitted changes and move the branch pointer, leading to potential data loss if not used carefully.
Its exact behavior can vary slightly depending on the specific implementation (e.g., from git-extras vs. a custom script), so it's always good to understand what it does under the hood.

To revert the last commit, creating a new commit that undoes its changes:
git undo

To revert a specific commit identified by its hash:
git undo 1a2b3c4d

To reset the branch to the previous commit, discarding all local uncommitted changes (use with caution, this is destructive):
git undo --hard

To reset the branch to the previous commit, keeping the changes from that commit in the staging area:
git undo --soft

To reset the branch to the previous commit, keeping the changes from that commit in the working directory as unstaged changes:
git undo --mixed

The concept of a simple "undo" command in Git arose from the common need to quickly reverse recent changes without needing to remember the intricacies of git revert or git reset. While not part of the core Git distribution, various third-party projects and individual users have created versions of git-undo to streamline workflows. A notable implementation is found within git-extras, a popular collection of community-contributed Git utilities, which integrates git-undo as a convenient wrapper around frequently used undo operations. Its development is driven by the desire to make Git more approachable for everyday tasks.

git-revert(1), git-reset(1), git-restore(1), git-checkout(1)