Understanding the Command 'git worktree' (with examples)

The git worktree command is a powerful feature within Git that allows users to manage multiple working trees simultaneously attached to the same Git repository. This capability enables developers to maintain different branches or work on separate features, bug fixes, or experiments independently, reducing the need to constantly switch between branches and stash changes. By using git worktree, developers can streamline workflows, improve productivity, and avoid disruption due to constant context switching.

Use case 1: Create a new directory with the specified branch checked out into it

Code:

git worktree add path/to/directory branch

Motivation: In a collaborative development environment, it’s common to work on multiple features or bug fixes simultaneously. By checking out a specified branch into a new directory, you can keep your current working environment undisturbed. This is useful for keeping the main workspace productive while exploring new ideas or tackling issues on separate branches.

Explanation: This command creates a new working directory at the specified path (path/to/directory) and checks out the existing branch (branch) into it. This allows you to work on different branches without having to change the context of your main repository directory, supporting parallel development efforts.

Example Output:

Preparing worktree (checking out 'branch')
HEAD is now at [commit_hash] Commit message description

Use case 2: Create a new directory with a new branch checked out into it

Code:

git worktree add path/to/directory -b new_branch

Motivation: This use case is particularly helpful when you need to start developing a new feature or experiment with new ideas without affecting your current branch. By creating a new branch and checking it out into a separate directory, you ensure that the integrity and state of your existing branches remain untouched.

Explanation: This command initializes a new directory (path/to/directory) and creates (-b) a new branch (new_branch) within it. The -b flag is crucial here, instructing Git to create the new branch before checking it out into the specified directory. This setup encourages isolated branching for experimental or new feature development purposes.

Example Output:

Preparing worktree (new branch 'new_branch')
Branch 'new_branch' set up to track remote branch 'new_branch' from 'origin'.

Use case 3: List all the working directories attached to this repository

Code:

git worktree list

Motivation: Over time, with multiple worktrees attached to a single repository, it’s essential to have a command that can quickly give an overview of all active worktrees. This use case is helpful for managing and organizing these worktrees, allowing you to see which branches are simultaneously being worked on.

Explanation: The git worktree list command provides a list of all directories that are currently attached to the repository, detailing information like the path to the directory, the branch checked out, and the associated commit. This comprehensive view aids in understanding the different directions the codebase is currently taking.

Example Output:

/path/to/first_worktree                   [branch_a] dfd9a24 Last commit message A
/path/to/second_worktree                  [branch_b] e3b0c44 Last commit message B

Use case 4: Remove a worktree (after deleting worktree directory)

Code:

git worktree prune

Motivation: Over time, you may find that some worktrees are no longer needed, perhaps after a feature is merged or a bug is fixed. Managing storage and repository clutter becomes necessary. The git worktree prune command is particularly useful for cleaning up references to deleted worktree directories, ensuring the repository remains manageable and that obsolete configurations do not linger.

Explanation: The git worktree prune command cleans up working tree administrative data. After manually removing the directory of a worktree, this command updates the Git repository to remove references to that worktree. It’s a housekeeping step that keeps Git’s internal structure consistent with your current file structure.

Example Output:

Pruning worktree: /path/to/deleted_worktree

Conclusion

The git worktree command is a versatile tool that provides significant advantages in Git-based development workflows. By managing multiple working trees tied to the same repository, developers can enhance productivity, streamline concurrent workflows, and maintain a clean and organized development environment. Each use case presented above demonstrates unique capabilities of git worktree, illustrating its role in modern software development practices.