Your First Repository

Create a Git repository with git init, look inside the .git folder, and learn to read git status

Make a project folder

Let’s create the project we’ll use for the rest of the course: the code for a small two-wheeled robot. Open a terminal and run:

mkdir pico-bot
cd pico-bot

mkdir makes a new folder and cd moves into it. Everything from now on happens inside pico-bot.

Turn it into a repository

To tell Git to start tracking this folder, run:

git init

Initialized empty Git repository in /home/kev/pico-bot/.git/

That’s it, pico-bot is now a Git repository. Git has created a hidden folder called .git inside it. List everything, including hidden files, to see it:

ls -a

.  ..  .git

The .git folder is where Git keeps every commit, every branch and all its settings for this project. You never need to edit anything inside it. Just know that this folder is the repository: if you delete it, Git forgets the whole history (your normal files stay where they are).

One repository per project

Run git init in the top folder of each project, not in your home folder or your whole Documents folder. If you accidentally run it in the wrong place, just delete the .git folder that it created.

Ask Git what’s going on

The command you’ll use more than any other is git status. It tells you what branch you’re on and what has changed since your last commit. Try it now:

git status

On branch main

No commits yet

nothing to commit (create/copy files and use "git add" to track)

Nothing to see yet, because the folder is empty. Let’s add a file. Create a file called main.py in the pico-bot folder with your editor, and put this in it:

# Pico-Bot: a simple two-wheeled robot
from machine import Pin
import time

led = Pin("LED", Pin.OUT)

print("Pico-Bot starting up")
for _ in range(3):
    led.toggle()
    time.sleep(0.5)

Save it and run git status again:

On branch main

No commits yet

Untracked files:
  (use "git add <file>..." to include in what will be committed)
	main.py

nothing added to commit but untracked files present (use "git add" to track)

Git has noticed main.py, but it’s untracked: Git can see the file, but isn’t saving its history yet. Git never starts tracking a file until you tell it to. In the next module you’ll do exactly that, and make your first commit.

Reading git status

git status is your best friend. Get into the habit of running it before and after every other Git command. It tells you:

• Which branch you’re on
• Untracked files: new files Git isn’t tracking yet
• Changes not staged for commit: tracked files you’ve edited
• Changes to be committed: changes you’ve marked to go in the next commit

Even better, it usually tells you which command to run next, in the brackets.

If you prefer something shorter, try:

git status --short

?? main.py

?? means untracked. You’ll meet other letters such as M (modified) and A (added) soon.

Getting a project that already exists

There’s a second way to get a repository: copy someone else’s with git clone. You’ll use that in module 10, once we’ve covered GitHub. For now, git init is all you need.

Try it yourself

1. Create the pico-bot folder, run git init, and check ls -a shows the .git folder.
2. Create main.py and run git status.
3. Create a second file called README.md containing # Pico-Bot. Run git status --short. How many untracked files are there now?

Common issues

• Problem: fatal: not a git repository (or any of the parent directories): .git
• Solution: cd into your project folder, or run git init if it isn’t a repository yet.

• Why: Git commands only work inside a repository. Git looks for a .git folder in the current folder and every folder above it.

• Problem: git status lists hundreds of files from all over your computer
• Solution: You’ve run git init in your home folder. Delete the .git folder there (rm -rf ~/.git, double-check the path first!) and run git init in the project folder instead.

• Why: Git tracks everything inside the folder where you ran git init.

• Problem: You can’t see the .git folder
• Solution: Use ls -a, or turn on hidden files in your file manager (Cmd + Shift + . on a Mac).
• Why: Names starting with a dot are hidden by default.

Check your understanding

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