When you’re learning Git (or anything for that matter) rapid and cheap testing, feedback, and failure can expedite the learning process from hours to minutes!

When you’re learning and experimenting with Git concepts like:

• Branching,
• Merging,
• Tagging,
• The Working directory,
• The Cache (or Index),
• Reading the Commit History,
• Or basically any Git command or concept

You want to have the freedom to make mistakes, even to the point of corrupting the entire Git repository (repo).

Essentially, a “Git Repo Sandbox” that you can rebuild in seconds.

Here is my code to quickly (re)create said “Git Repo Sandbox” that contains:

• 2 Branches (master and dev)
• 1 Merge

Just copy and paste the following code into your bash prompt and let it rip.

There is a merge-conflict warning but it’s ignored because all we want is our “Git Repo Sandbox” up and running again:

rm -Rf ./git_test #<== be VERY careful with this line
mkdir ./git_test
cd git_test
sleep 1

git init
echo ":)" >> ./script.sh
git add *
git commit -m "Commit message"
echo ":)" >> ./script.sh
git add *
git commit -m "Commit message"
sleep 1

git branch dev
git checkout dev
echo ":)" >> ./script.sh
git add *
git commit -m "Commit message"
echo ":)" >> ./script.sh
git add *
git commit -m "Commit message"
sleep 1

git checkout master
echo ":)" >> ./script.sh
git add *
git commit -m "Commit message"
sleep 1

git merge dev
git add *
git commit -m "Commit message"
sleep 1

git log --oneline --all --graph --decorate

You will get output similar to the following (only difference is commit hashes):

Here’s a live demo on how to use my code. For me, I performed a Right-click on my mouse to paste:

Now you can study and experiment with as many git concepts and commands to your heart’s content. Or at least, what this simple repository will allow.

You don’t have to worry about making a mistake, because if you corrupt everything, just “re-build and reload”.

Love Git Branches But Hate Reading Them?

If you’re using git branching, it can be difficult sometimes to orient yourself within your git repository (repo).

Knowing where you are, where you want to go, and how to get there is next to impossible if you don’t know how to read your commit history (branches)

So I’m going to show you how to read your commit history in this post.

Commits

Here’s your first insight: Commits always point BACK to their parent commit(s), never forward to their child commit(s):

If you make some changes and commit again, the next commit stores a pointer to the commit that came immediately before it.

3.1 Git Branching – Branches in a Nutshell, Figure 10.

This subtle distinction may not seem like a big deal now, but soon this will make all the difference.

Reading Commits

Here is the output of the branch master from my local repo:

git log --oneline --graph --decorate

Given that commits always point back, we can trace our branch from Branch Pointer master (78f107a) all the way back down to our initial commit (7bc8a7a):

The totality of the entire trail from the most recent commit master (78f107a) all the way back down to our initial commit (7bc8a7a) is one branch.

Reading Multiple Branches

Here is where knowing commits point back, not forward, is REALLY going to help us out

First we expose ALL branches from my git repo:

git log --oneline --graph --decorate --all

In this output we now can see all branches laid out at once.

Reading the dev Branch

Here are a couple of things to remember when reading the commit history from command ‘git log’:

1. The previous commit(s) is denoted by following back to the previous asterisk(s), not necessarily the commit beneath it.
2. The vertical and diagonal bars actually do a great job of guiding us to the previous commit(s).

7bc8a7a <= a6b939a <= 8e005a4 <= 0461fc6 <= 5e3384e (dev)

We can confirm this by checking out the dev branch and listing the commit history

Reading the test Branch

Just repeat the same process for branch test and you will get the following:

Confirming the test branch:

7bc8a7a <= a6b939a <= 8e005a4 <= e5a2bcc <= 3d6f3bb (test)

Summary

Now that you know how to read your commit history (branches) you should be able to orient yourself and navigate within your git repo.

Hopefully this will empower you to leverage git branches more when you need to experiment with different version and features of your code.

Branches will allow you to test your experimental code without losing the production code.