git-workshop/01_essentials/03-branching

Module 03: Branching Basics

Learning Objectives

In this module, you will:

• Understand what a branch is in Git
• Create new branches using git branch or git switch -c
• Switch between branches using git switch
• View all branches with git branch
• Understand that branches allow parallel development

Challenge

Setup

Run the setup script to create your challenge environment:

.\setup.ps1

This will create a challenge/ directory with a Git repository that has some initial commits on the main branch.

Your Task

Your goal is to create a feature branch, make commits on it, and understand how branches work independently.

Steps:

1. Create a new branch called feature-login
2. Switch to the new branch
3. Create a new file login.py with some login functionality
4. Commit the new file to your feature branch
5. Make another change to login.py and commit it
6. Switch back to the main branch and observe that login.py doesn't exist there

Suggested Approach:

1. Navigate to the challenge directory: cd challenge
2. View existing branches: git branch
3. Create and switch to new branch: git switch -c feature-login
4. Create login.py with any content you like
5. Stage and commit: git add login.py and git commit -m "Add login functionality"
6. Modify login.py, then commit again
7. Switch back to main: git switch main
8. Run ls (or check your file explorer) and notice that login.py doesn't exist on main!
9. Switch back to feature-login: git switch feature-login
10. Run ls (or check your file explorer) again and see that login.py is back!

Important Notes:

• Use git switch to change branches
• git switch -c <name> creates and switches in one command
• Branches are independent - files in one branch don't affect another until you merge
• You can switch between branches as many times as you want

Key Concepts

• Branch: A lightweight movable pointer to a commit. Branches allow you to work on different features independently.
• HEAD: A pointer to the current branch you're working on. When you switch branches, HEAD moves.
• main/master: The default branch name in Git (main is the modern convention, master is older).
• Feature Branch: A branch created to develop a specific feature, separate from the main codebase.

Useful Commands

git branch                   # List all branches (* shows current)
git branch <name>            # Create a new branch
git switch <branch>          # Switch to an existing branch
git switch -c <name>         # Create and switch to new branch
git switch -                 # Switch back to previous branch
git branch -d <name>         # Delete a branch (we won't use this yet)

Verification

Once you've completed the challenge, verify your solution:

.\verify.ps1

The verification script will check that you've created the branch, made commits, and that the branches are independent.

Need to Start Over?

If you want to reset the challenge and start fresh:

.\reset.ps1

This will remove the challenge directory and run the setup script again, giving you a clean slate.