What is Git & GitHub? – Create & Merge Branches

🇯🇵 日本語版: 02_Branches.md

This section goes over Git branches and how to work with your first branch.

Overview Overview

• Overview Overview
• git branch command
  • git branch
• Create a new branch
  • git checkout -b <branch name>
• Add a file to the develop branch
  • Verify on GitHub Desktop App
• See the changes on GitHub
• Create & Merge a Pull Request
• Update local repo from GitHub repo
• What is Git Branch?
  • What is a branch?
  • Why use a branch?
• Branch and website
• Git Push vs Pull –Teamwork
• Hands-on C Review
• GitHub Workflow
  • Detailed Overview of the GitHub Workflow
• GitHub Overview-GitHub Website Overview
  • GitHub Repository
  • GitHub Issues
  • GitHub Pull Request
  • Overview of GitHub
• GitHub parts
• Quiz time
• Next Section

git branch command

1. First, go back to the learning_git repository

    cd Documents/learning_git
   

2. Use git branch command to see all of the branches in your repo & which branch you are currently on.

    git branch
   
    * main
   

git branch

• git-branch
• Command to display branch list
• The branch with an asterisk (*) is the current branch
• If your default branch name is master, change it with the following command:
  • git config --global init.defaultBranch main

Create a new branch

First, let’s create a branch named develop and switch to it.

  git checkout -b develop

  ...

  Switched to a new branch 'develop'

git checkout -b <branch name>

• This command creates a new branch in the repo & switches to it.
• git-checkout Doc

Add a file to the develop branch

1. Create a file on the develop branch

    touch develop_file.md
   

2. Use git add & git commit commands to save it in your local repo

    git add develop_file.md
    git commit -m "develop only"
   

    [develop 4f98baf] develop only
    1 file changed, 0 insertions(+), 0 deletions(-)
    create mode 100644 develop_file.md
   

3. Use git status command to verify changes

    git status
   

    On branch develop
    nothing to commit, working tree clean
   

4. Use git push command to upload changes to GitHub

    git push -u origin develop
   

    Enumerating objects: 4, done.
    Counting objects: 100% (4/4), done.
    Delta compression using up to 4 threads
    Compressing objects: 100% (2/2), done.
    Writing objects: 100% (3/3), 277 bytes | 277.00 KiB/s, done.
    Total 3 (delta 0), reused 0 (delta 0), pack-reused 0
    remote: This repository moved. Please use the new location:
    remote:   https://github.com/ahandsel/learning_git_3.git
    remote:
    remote: Create a pull request for 'develop' on GitHub by visiting:
    remote:      https://github.com/ahandsel/learning_git_3/pull/new/develop
    remote:
    To https://github.com/ahandsel/learning_git_3.git
    * [new branch]      develop -> develop
    Branch 'develop' set up to track remote branch 'develop' from 'origin'.
   

Verify on GitHub Desktop App

Let’s verify the changes by viewing it on the GitHub Desktop App

1. Open the app with the following command:

    cd learning_git
    github .
   

2. App will open to a Add Local Repository setting page, click the Add Repository button

3. Click History Tab to view the changes you have made

   • 

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See the changes on GitHub

Go to the Network graph setting on your GitHub repo to see the changes you have made

• https://github.com/USER/REPO/network
• Example: https://github.com/ahandsel/Git_GitHub_Slides/network

---

Create & Merge a Pull Request

Pull RequestsSo, you can check other users’ changes etc. before the file is actually changed.

• Used for code reviews, etc.

developCreate in mainGitHub to merge the branch into the branch.Pull request

• Review your changes and Pull Requestmerge.

mainYou see two new files in your branch!

Update local repo from GitHub repo

main Let’s move to the branch.

git checkout main

Currently, GitHub repositories have more up-to-date files than local repositories.

  Switched to branch 'main'
  Your branch is behind 'origin/main' by 4 commits & can be fast-forwarded
    (use "git pull" to update your local branch)

Use the git pull command to handle this.

Pull the latest version of the repo from GitHub with git pull origin main

git pull origin main

remote: Enumerating objects: 1, done.
remote: Counting objects: 100% (1/1), done.
remote: Total 1 (delta 0), reused 0 (delta 0), pack-reused 0
Unpacking objects: 100% (1/1), 631 bytes | 210.00 KiB/s, done.
From https://github.com/ahandsel/kintone_dojo
* branch            main     -> FETCH_HEAD
  5f9f89b..1438ca5  main     -> origin/main
Updating d775d42..1438ca5
Fast-forward
2nd_file.md     | 0
develop_file.md | 0
2 files changed, 0 insertions(+), 0 deletions(-)
create mode 100644 2nd_file.md
create mode 100644 develop_file.md

Now the mainbranch and developthe branch are in the same state,
so developlet’s delete the branch.

git branch -d develop

  Deleted branch develop (was c6e6c83).

git branchLet’s check with the command

git branch

  * main

What is Git Branch?

What is a branch?

• A moving pointer to the commit.
• It can be managed in multiple timelines and changed without affecting the mainline.
• git checkout
  • Command to switch branches.
• git branch -d <branch-name>
  • Command to delete a branch.

Why use a branch?

• To separate stable version, development version, experimental version, etc.
• Example: This GitHub slide
  • Each hands-on and concept section can be a branch.
  • You can develop each at the same time.

Ref: Git - Branches in a Nutshell

Branch and website

mainIn the branch, there is code that runs the website.

• If mainchanges are made in the branch, it will affect the user! !!

If two developers want to change their website at the same time, create three branches

• main→ Live code
• feature_A→ Implemented by developer A
• feature_B→ Implemented by developer B

When development is complete, merge the branches!

Git Push vs Pull –Teamwork

git push	git pull
Upload command	Download command
“Push” forces changes to the target repository.	“Pull” gets changes from the target repository
[あなたのコード] ⟾ プッシュ ⟾ [ターゲット]	[あなたのコード] ⏎ プル ⏎ [ターゲット]
A “push request” is a target repository that requests you to push changes.	A “pull request” is to request the target repository to get changes.

Hands-on C Review

git checkout -b develop	Command to switch branches
Reasons to use a branch	Separate code development, testing, public version, etc.
Pull RequestsWhengit pull	A “pull request” is to request the target repository to get changes.

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GitHub Workflow

Understanding the GitHub flow - GitHub Guides

#	Step	Notes
1	Create a branch	mainfeatureCreate a branch from and start development
2	Commit changes	After the code implementation is complete, commitcreate. You\
commitcan check the change history by creating, and you can roll back and refer to it.
3	Open a Pull Request	When you’re ready to share your implementation with others, create a Pull Request.
Four	Discuss & Review Code	Get code reviews from teen members and discuss them.
Five	Deploy & Test	Deploy the code to your test environment to make sure it works.
6	Merge to main	The implementation is now in effect and the Pull Request keeps a record of changes to your code.

Detailed Overview of the GitHub Workflow

Git Common-Flow 1.0.0-rc.5 –Git Common Flow

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GitHub Overview-GitHub Website Overview

GitHub Repository

GitHub Repository –Code

• A container that holds all the files related to your project, such as code and documentation.
• All files stored on GitHub are versioned with git
• Repositories are often abbreviated as “repo”
• It is a file to display the introduction of the project etc. displayed at the bottom of the repository.

GitHub Issues

• Where users discuss the contents of the repository
• You can assign issues to users and add labels to make them easier to read.

GitHub Pull Request

• Used when the user wants to make changes to the repository
• Example: When you want to add a new README.md file

Overview of GitHub

Project boards: Task boards in KANBAN format

Wiki: Allows you to create and save related project documents

Insight: Repository analysis tool

• Network Graph: Visualize commits and branches in the timeline
• Pulse: Shows tasks in progress or completed

GitHub parts

Branch	Code alternative timeline\
example: main, Development, Feature / xxx
Commit	Save file changes to repository
Pull Request	Share your proposed changes with others
Merge Pull Request	Actually change the branch (main etc.) and update

Quiz time

• What does the git checkout -b develop command do?
• Why use a branch?
• What is a Pull Request?

Next Section

Revert - 03_Revert_EN.md

List of Lecture Guides

README_EN.md ⚙️