Skip to main content

4.1 Practical

Branching, merging, and pull requests

In this practical, you’ll create a new branch, make some changes, and then merge those changes back using GitHub’s web interface.

Our branching workflow

Remember the branching process:

  • We create a new branch from main (git branch <branch-name>)
  • We switch to our new branch (git checkout <branch-name> or git switch <branch-name>)
  • We make changes, add, and commit as usual
  • We *push our branch to GitHub (git push origin <branch-name>)
  • We create a pull request on GitHub to merge our changes
  • We merge the pull request and delete the branch

Step 1: Create and switch to a new branch

  1. Check your current branch and status:

    git status
git branch

  2. Create a new branch called feature-bio:

    git branch feature-bio

  3. Switch to your new branch:

    git checkout feature-bio

    Or use the newer syntax:

    git switch feature-bio

  4. Verify you’re on the new branch:

    git branch

    You should see an asterisk () next to feature-bio*

TipShortcut!

You can create and switch to a new branch in one command: git checkout -b feature-bio or git switch -c feature-bio

Step 2: Make changes on your branch

  1. Create a new file called about.md:

    touch about.md

  2. Edit the file and add some content about yourself:

    # About Me

## Bio
Write a few sentences about yourself here.

## Research Interests
- List your research areas
- Or hobbies if you prefer!

## Fun Fact
Share something interesting about yourself.

  3. Add and commit your changes:

    git add about.md
git commit -m "Add personal bio page"

Step 3: Push your branch to GitHub

  1. Push your branch to GitHub:

    git push origin feature-bio

  2. Check the output - git will give you a link to create a pull request!

Step 4: Create a pull request on GitHub

  1. Go to your repository on GitHub in your browser

  2. You should see a yellow banner saying “Compare & pull request” - click it!

    If you don’t see it:

    • Click the “Branch” dropdown and select feature-bio
    • Click “Contribute” → “Open pull request”

  3. Fill in the pull request details:

    • Title: Something descriptive like “Add personal bio page”
    • Description: Explain what changes you made
    • Review the changes in the “Files changed” tab

  4. Click “Create pull request”

Step 5: Review and merge the pull request

  1. Review your pull request:
    • Check the “Files changed” tab to see your modifications
    • Look at the “Checks” (if any are running)
  2. Merge the pull request:
    • Click “Merge pull request”
    • Click “Confirm merge”
    • Optionally click “Delete branch” to clean up

Step 6: Update your local repository

  1. Switch back to main branch:

    git checkout main

  2. Pull the latest changes:

    git pull origin main

  3. Verify your changes are now in main:

    ls
cat about.md

  4. Clean up your local branch (optional):

    git branch -d feature-bio
  • Use git branch to list all branches
  • Use git branch <name> to create a new branch
  • Use git checkout <name> or git switch <name> to switch branches
  • Use git push origin <branch-name> to push a branch to GitHub
  • Always create pull requests for important changes - even when working alone!
  • Pull requests provide a record of what changed and why

Challenge: Try it again!

Create another branch, make different changes (maybe edit your README.md), and go through the pull request process again!