Comprehensive Guide to Essential Git Commands

Git is a powerful version control system widely used by developers to manage code and collaborate on projects. This guide provides a cheat sheet of essential Git commands, categorized for easy reference. Whether you're new to Git or an experienced user, these commands will help streamline your workflow.

Basic Commands

Master Branch

• master: The default development branch.

HEAD

• HEAD: Represents the current commit.
• HEAD^: Parent of HEAD.
• HEAD~4: Fourth ancestor of HEAD.

Branch Navigation

• foo...bar: From branch foo to branch bar.

Help

• git help [command]: Displays help information for a specific command.

Creating Repositories

From Existing Files

• git init: Initializes a new Git repository.

From Existing Repository

• git clone [URL]: Clones an existing repository from a specified URL.

Publishing Changes

Committing Changes

• git commit -a: Commits all changed files.
• git commit -m "[msg]": Commits with a message.
• git commit -am "[msg]": Adds and commits with a message.

Tagging and Remote

• git tag [name]: Tags the current version.
• git remote add origin [URL]: Adds a remote repository.
• git push: Pushes changes to the remote repository.

Updating Repositories

Fetching and Pulling

• git fetch: Fetches from the default upstream.
• git pull: Fetches and merges from the remote repository.

Patching

• git am [patch.mbox]: Applies a patch from a mailbox.
• git apply [patch.diff]: Applies a patch directly.

Viewing Changes

• git status: Shows the status of changes.
• git diff [old] [new]: Shows differences between commits.
• git log [-p] [file | dir]: Shows the commit log.
• git blame [file]: Shows who changed each line.
• git show [id]: Displays commit metadata.
• git shortlog: Provides a summary of commits.
• git tag -l: Lists tags.

Reverting Changes

• git reset --hard: Resets without undo.
• git reset: Resets to the last commit.
• git revert [commit]: Reverts a specific commit.
• git commit --amend: Amends the last commit.
• git checkout [id] [file]: Checks out a file from a specific commit.

Branch Management

• git checkout [branch]: Switches branches.
• git merge [branch]: Merges specified branch into the current branch.
• git branch [branch]: Creates a new branch.
• git branch -d [branch]: Deletes a branch.

Handling Conflicts

• git diff [--base]: Shows base diff.
• git diff --ours: Shows diff from our side.
• git diff --theirs: Shows diff from their side.
• git log --merge: Logs merges.
• gitk --merge: Visual merge tool.

Useful Tools

• git archive: Creates a release tarball.
• git bisect: Binary search for defects.
• git cherry-pick: Takes a single commit.
• git fsck: Checks repository integrity.
• git gc: Compresses metadata.
• git rebase: Forwards local changes.
• git remote add [URL]: Adds a remote URL.
• git stash: Temporarily sets aside changes.

Tracking Files

• git add [files]: Adds files to staging.
• git rm [files]: Removes files.
• git mv [old] [new]: Renames files.
• git ls-files: Lists files in the working directory.

Local Repository Structure

• Working Directory: The directory where you work on files.
• Local Repository: Contains the current branch and other branches.
• Remote Repository: The origin repository for push and pull operations.

Command Flow

1. Create: git init or git clone.
2. Browse: git status, git log, git diff.
3. Change: git add, git commit.
4. Revert: git reset, git checkout.
5. Update: git fetch, git pull.
6. Branch: git branch, git checkout.
7. Commit: git commit.
8. Push: git push.

This guide should serve as a quick reference for essential Git commands. Mastering these commands will enhance your efficiency and collaboration in any Git-based project.