🌿 Branching¶

Branching allows you to work on multiple versions of your code simultaneously, enabling parallel development and experimentation.

✅ What is a Branch?¶

A branch is an independent line of development. Think of it as a parallel workspace where you can make changes without affecting other work.

main (production) ────●──────────────●────
                     │
feature/login (branch)●──●──●─────

✅ Why Use Branches?¶

Isolate features - Work on new features without breaking production
Bug fixes - Fix urgent bugs without disturbing ongoing work
Experiments - Try new ideas safely; discard if they don't work
Code review - Prepare branches for review before merging
Releases - Maintain separate release branches

✅ Default Branch¶

Traditionally called master, now commonly called main. This is your main production-ready branch.

✅ Listing Branches¶

# List all local branches
git branch

# List all branches (including remote)
git branch -a

# List branches with latest commit info
git branch -v

# Show branches in color and with merge status
git branch --color

✅ Creating Branches¶

# Create a new branch but stay on current branch
git branch feature-login

# Create and switch to the new branch
git checkout -b feature-login

# Or with git switch (newer command)
git switch -c feature-login

# Create branch from a specific commit
git branch feature-login abc1234

# Create branch from a specific tag
git branch v2.0 v2.0.0

✅ Switching Branches¶

# Switch to an existing branch
git checkout feature-login

# Or with git switch (newer command, Git 2.23+)
git switch feature-login

# Switch to the previous branch
git checkout -

# Or
git switch -

Important: Switching branches updates your working directory to match the target branch's files. Uncommitted changes may block switching.

✅ Renaming Branches¶

# Rename current branch
git branch -m new-name

# Rename a specific branch
git branch -m old-name new-name

# Renaming while checked out
git branch -m feature-login feature-auth

✅ Deleting Branches¶

# Delete a local branch (must be merged or safe to delete)
git branch -d feature-login

# Force delete a branch (even if not merged)
git branch -D feature-login

# Delete a remote branch
git push origin --delete feature-login

# Or push with : syntax
git push origin :feature-login

✅ Tracking Branches¶

A tracking branch connects a local branch to a remote branch:

# Create branch that tracks a specific remote branch
git checkout -b local-name origin/remote-name

# Set tracking for existing branch
git branch --set-upstream-to=origin/main main

# Show tracking info
git branch -vv

✅ Viewing Branch History¶

# Show commits in current branch only
git log main..feature-login

# Show commits in both branches
git log --oneline --graph --all

# Show differences between branches
git diff main feature-login

# Show files changed between branches
git diff --name-only main feature-login

✅ HEAD Reference¶

HEAD points to your current location:

# HEAD usually points to a branch
HEAD -> main -> commit

# Detached HEAD: points directly to a commit
HEAD -> commit (not a branch)

# See what HEAD points to
git symbolic-ref HEAD

# See what commit HEAD points to
git rev-parse HEAD

✅ Detached HEAD State¶

When HEAD points directly to a commit (not a branch), you're in "detached HEAD" state:

# Checkout a specific commit (detached HEAD)
git checkout abc1234

# Make changes and create a new branch
git checkout -b hotfix

# Now HEAD -> hotfix -> commit (normal state)

Use cases: - Inspecting old commits - Creating branches from specific points - Testing specific states

✅ Branch Naming Conventions¶

Pattern	Purpose	Example
`feature-*`	New features	`feature-login`, `feature-dark-mode`
`bugfix-*`	Bug fixes	`bugfix-memory-leak`
`hotfix-*`	Urgent production fixes	`hotfix-critical-security`
`release-*`	Release preparation	`release-v2.1`
`fix-*`	Simple fixes	`fix-typo`, `fix-formatting`
`refactor-*`	Code refactoring	`refactor-auth-module`
`test-*`	Experimental	`test-new-algorithm`
`docs-*`	Documentation	`docs-api-guide`

✅ Typical Branch Workflow¶

# 1. Start on main
git checkout main
git pull origin main

# 2. Create feature branch
git checkout -b feature-user-profile

# 3. Make changes and commits
git add .
git commit -m "Add user profile page"

# 4. Merge back to main (when done)
git checkout main
git merge feature-user-profile

# 5. Delete feature branch
git branch -d feature-user-profile

✅ Comparing Branches¶

# Show commits in branch A not in branch B
git log branchB..branchA

# Show commits unique to each branch
git log --left-right branchB...branchA

# View file changes between branches
git diff main feature-login

# View file content at a branch
git show feature-login:app.py

✅ Saving Work When Switching¶

If you have uncommitted changes:

# Stash changes temporarily
git stash

# Switch branches
git checkout main

# Work on main...

# Return to feature branch
git checkout feature-login

# Restore stashed changes
git stash pop

✅ Best Practices¶

Short-lived branches - Keep branches small and focused
Descriptive names - Use clear, purposeful branch names
Clean up - Delete merged branches regularly
Update frequently - Rebase or merge main into your branch often
Atomic commits - Make small, focused commits on branches
No commits on main - Keep main clean; do work on branches

🔍 Key Takeaways¶

Branches enable parallel development without conflicts
git branch creates, lists, renames, and deletes branches
git checkout or git switch changes your current branch
Feature branches should be short-lived and focused
Use consistent naming conventions
Clean up merged branches to keep your repository clean

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