git-expert

name	git-expert
description	Provides expert guidance on advanced Git concepts, commands, and best practices. Use for complex version control scenarios, Git internals, recovery from mistakes, and optimizing Git workflows.

Git Expert

This skill offers in-depth knowledge and practical advice for navigating complex Git scenarios, understanding Git's underlying mechanics, and effectively recovering from common version control challenges.

Core Principle

"Master Git to master your codebase. Understand the 'why' behind the 'what' to wield version control with confidence."

When to Use This Skill

Use this skill when you need to:

• Perform advanced Git operations like rebasing, cherry-picking, or bisecting.
• Understand core Git concepts such as the staging area, HEAD, and different merge strategies.
• Recover from Git mistakes (e.g., lost commits, accidental resets).
• Optimize your Git workflow or troubleshoot complex repository states.
• Clean up commit history or manage large files within Git.
• Set up custom Git configurations or hooks.

Key Concepts

• Three States of a File: Working Directory, Staging Area (Index), Git Directory (Committed).
• Git Objects: Blobs, Trees, Commits, Tags – how Git stores your data.
• Pointers and References (Refs): Branches, HEAD, and how they navigate your commit history.
• Fast-Forward vs. Three-Way Merge: Understanding different merge strategies.

Workflows & Commands

This skill guides you through advanced Git scenarios. Refer to the bundled reference files for detailed explanations and command examples.

1. Advanced Git Commands

Explore powerful commands that go beyond basic commit, push, and pull:

• git rebase: For linearizing history and integrating changes.
• git cherry-pick: To apply specific commits across branches.
• git reflog: Your safety net for recovering lost work.
• git bisect: For efficiently finding the commit that introduced a bug.
• git filter-repo: For rewriting repository history (e.g., removing large files).
• Git Hooks: Custom scripts to automate actions at specific points in the Git workflow.

Reference: See ADVANCED-GIT-COMMANDS.md for detailed usage.

2. Git Core Concepts

Gain a deeper understanding of how Git works internally:

• The three states of a file and their implications.
• How Git stores data as objects.
• The role of pointers like HEAD and branches.
• The origin remote and how it connects your local repo to GitHub.
• Detailed breakdown of merge strategies.

Reference: See GIT-CONCEPTS.md for conceptual explanations.

3. Git Recovery: Undoing Mistakes

Learn how to safely undo changes and recover from common Git blunders:

• Discarding changes in the working directory or staging area.
• Amending the last commit.
• Undoing (resetting) commits locally.
• Reverting commits (creating new commits to undo previous ones, safe for shared history).
• Using git reflog as a powerful recovery tool.
• Stashing changes when switching contexts.

Reference: See GIT-RECOVERY.md for step-by-step recovery procedures.

Power Move

"Before making any potentially destructive changes (like git reset --hard or git rebase), always perform a git reflog and save its output. This provides a safety net for almost any recovery scenario."

Troubleshooting

• "Detached HEAD" state: Understand that HEAD is pointing directly to a commit, not a branch. Create a new branch if you want to make new commits from this point.
• Merge Conflicts: Refer to references/git-recovery.md for resolution strategies, and advanced techniques might involve git mergetool.
• "Rewriting history" warnings: Remember that operations like rebase and amend change commit hashes. Avoid these on shared branches unless absolutely necessary and coordinated with your team.