Git

Introduction Git is a version control system that tracks changes in code and helps developers collaborate efficiently. GitHub is an online platform that hosts Git repositories, making it easier to share code, manage projects, and work on open-source projects. Getting Started Initial Configuration git config --global user.name "your-name" git config --global user.email "your-email" git config --global core.editor "code" # Set default editor git config --list # View all configurations Creating Repositories git init # Initialize a new repository git clone <repo-url> # Clone an existing repository git clone <repo-url> <folder-name> # Clone into specific folder Basic Workflow Staging Changes git status # Check current status git add <file> # Stage a specific file git add . # Stage all files git add *.js # Stage all JavaScript files git rm <file> # Remove file and stage deletion git mv <old-name> <new-name> # Rename file and stage change Committing Changes git commit -m "Describe your changes here" git commit -am "Add and commit tracked files" git commit --amend -m "Update last commit message" git commit --amend --no-edit # Add staged changes to last commit Viewing History git log # View commit history git log --oneline # Compact commit history git log --graph --oneline --all # Visual branch history git log -p # Show changes in each commit git log -n 5 # Show last 5 commits git show <commit-hash> # Show specific commit details git diff # Show unstaged changes git diff --staged # Show staged changes git diff <branch1> <branch2> # Compare branches Branching & Merging Managing Branches git branch # List all local branches git branch -a # List all branches (local and remote) git branch <branch-name> # Create a new branch git checkout <branch-name> # Switch to a branch git checkout -b <branch-name> # Create and switch to new branch git switch <branch-name> # Modern way to switch branches git switch -c <branch-name> # Create and switch to new branch git branch -d <branch-name> # Delete branch (safe) git branch -D <branch-name> # Force delete branch git branch -m <new-name> # Rename current branch Merging git merge <branch-name> # Merge branch into current branch git merge --no-ff <branch-name> # Merge with merge commit git merge --squash <branch-name> # Squash commits before merging git merge --abort # Abort merge in case of conflicts Rebasing git rebase <branch-name> # Rebase current branch git rebase -i HEAD~3 # Interactive rebase last 3 commits git rebase --continue # Continue after resolving conflicts git rebase --abort # Abort rebase operation Working with Remotes Remote Management git remote # List remote connections git remote -v # List remotes with URLs git remote add origin <repo-url> # Add remote repository git remote set-url origin <new-url> # Change remote URL git remote rename <old-name> <new-name> # Rename remote git remote remove <remote-name> # Remove remote git remote show origin # Show remote details Syncing with Remotes git fetch # Download remote changes (no merge) git fetch origin # Fetch from specific remote git fetch --all # Fetch from all remotes git pull # Fetch and merge remote changes git pull --rebase # Fetch and rebase instead of merge git push # Push changes to remote git push -u origin <branch-name> # Push and set upstream git push origin --delete <branch-name> # Delete remote branch git push --force # Force push (use with caution!) git push --force-with-lease # Safer force push git push --tags # Push all tags to remote Undoing Changes Working Directory & Staging git checkout -- <file> # Discard changes in working directory git restore <file> # Modern way to discard changes git restore --staged <file> # Unstage file git reset <file> # Unstage file (keep changes) git reset --hard # Discard all local changes git clean -fd # Remove untracked files and directories git clean -n # Preview files to be removed Commits git reset --soft HEAD~1 # Undo last commit (keep changes staged) git reset --mixed HEAD~1 # Undo last commit (keep changes unstaged) git reset --hard HEAD~1 # Undo last commit (discard changes) git reset --hard <commit-hash> # Reset to specific commit git revert <commit-hash> # Create new commit that undoes changes git revert HEAD # Revert last commit Stashing Temporary Storage git stash # Stash current changes git stash save "message" # Stash with description git stash list # List all stashes git stash show # Show latest stash changes git stash show stash@{0} # Show specific stash git stash apply # Apply latest stash (keep in list) git stash apply stash@{2} # Apply specific stash git stash pop # Apply latest stash and remove from list git stash drop # Delete latest stash git stash drop stash@{1} # Delete specific stash git stash clear # Delete all stashes git stash branch <branch-name> # Create branch from stash Tagging Version Marking git tag # List all tags git tag <tag-name> # Create lightweight tag git tag -a v1.0 -m "Version 1.0" # Create annotated tag git tag -a v1.0 <commit-hash> -m "Tag old commit" # Tag specific commit git show <tag-name> # Show tag details git push origin <tag-name> # Push specific tag git push origin --tags # Push all tags git tag -d <tag-name> # Delete local tag git push origin --delete <tag-name> # Delete remote tag Advanced Features Submodules git submodule add <repo-url> <path> # Add submodule git submodule init # Initialize submodules git submodule update # Update submodules git submodule update --init --recursive # Initialize and update all git submodule foreach git pull origin main # Update all submodules git submodule deinit <path> # Deinitialize submodule git rm <submodule-path> # Remove submodule Cherry-Picking git cherry-pick <commit-hash> # Apply specific commit to current branch git cherry-pick <hash1> <hash2> # Apply multiple commits git cherry-pick --continue # Continue after resolving conflicts git cherry-pick --abort # Abort cherry-pick operation Searching & Finding git grep "search-term" # Search in working directory git grep "search-term" <branch-name> # Search in specific branch git log -S "search-term" # Find commits with specific content git log --grep="pattern" # Search commit messages git bisect start # Start binary search for bug git bisect bad # Mark current commit as bad git bisect good <commit-hash> # Mark commit as good git bisect reset # End bisect session git blame <file> # Show who changed each line git reflog # Show reference logs (recover lost commits) Aliases git config --global alias.co checkout # Create alias git config --global alias.br branch git config --global alias.st status git config --global alias.unstage 'reset HEAD --' git config --global alias.last 'log -1 HEAD' git config --global alias.visual 'log --graph --oneline --all' GitHub-Specific Features Pull Requests & Collaboration # Fetch PR for local testing git fetch origin pull/123/head:pr-123 git checkout pr-123 # Working with forks git remote add upstream <original-repo-url> git fetch upstream git merge upstream/main GitHub CLI (gh) gh repo clone <repo-name> # Clone repository gh pr create # Create pull request gh pr list # List pull requests gh pr checkout <pr-number> # Checkout pull request gh issue create # Create issue gh issue list # List issues Practical Example: Push a Project to GitHub Configure Git: git config --global user.name "your-name" git config --global user.email "your-email" Initialize repository: git init Link to GitHub: git remote add origin <repo-url> Stage and commit: git add . git commit -m "Initial commit" Push to GitHub: git push -u origin main Your project is now live on GitHub! ...