How to use Git GUI
How to use Git GUI

  23 Sep 2014

Table of Contents

Introduction

Git is an important tool, both for the club and in the larger world of development. This is not an in-depth tutorial; rather, it discusses the basic steps needed to run git on the school computers.

Terms

  • Repository (repo): A place where the history of your work is stored.
  • Commit: When you have made changes to a repository and want them saved as part of its history, you commit these changes.
  • Push: When you want to move your repository’s history to a repo hosted online (like one on GitHub).
  • Fork: When someone branches their work off someone else’s to make their own changes. So, if an application I like has a blue background but I prefer pink, I could fork it and change the background.
  • Branch: Essentially a fork within your own repository. It allows you to experiment or make changes without risking your master branch.
  • master: The main branch of a repo. In general, it is best not to make changes directly to it, but instead to use it to keep up to date with the upstream repository.
  • Upstream: A term for the repository from which you forked. Your repository is downstream from it because information flowed downstream to you.

Typical Workflow

  1. Set up a repository (only if not done previously)
  2. Updating to upstream
  3. Creating a new branch for your changes
  4. Making any changes
  5. Committing and pushing changes

Setting Up a Repository

  1. Open the Git Gui application

    screenshot

  2. Select Clone Existing Repository

    screenshot

  3. Click on the white text box titled Source Location and paste in the HTTPS clone URL from your fork of the repo. Click the Browse button next to Target Directory and choose a directory.

    screenshot

  4. Click at the end of the white target directory box. Type out the name of the repository.

    screenshot

  5. Press the Clone button and wait for the operation to complete.

    screenshot

  6. Click Remote→Add. Fill in the name as upstream and the location as the HTTPS clone URL of the club’s repo. Press the add button.

    screenshot

Updating to Upstream

  1. In Git GUI, go to Branch→Checkout... and select master.

  2. Go to Remote→Fetch from→All.

  3. Click Repository→Git Bash

    screenshot

  4. Type the following commands:

    1. git reset --hard upstream/master
    2. git clean -fdx

  5. Go to Remote→Push... and in the dialog select master as the branch and origin as the remote.

  6. Your repository is now up to date with upstream! From here, you should create a branch.

If you already made a branch by mistake, check out your branch (Branch→Checkout... and select your branch) and type the following command into Git Bash: git rebase master

Creating a Branch

  1. Click Branch→Create.
  2. Fill in a descriptive name for your branch under Name.
  3. Select master under Starting Revision.
  4. Make any changes to the branch and commit them.
  5. To switch between branches, go to Branch→Checkout... and select the branch you want.

Committing and Pushing Changes

  1. Click the Rescan button, and then the Stage Changed button
  2. Type a descriptive message in the large text box in the bottom half of the window (In the imperative present tense, e.g. “Add Player class”)
  3. Click the Commit button
  4. Go to Remote→Push
  5. Select the branch you want to push (probably not master)
  6. You should now go on Github and submit a pull request by clicking the green button with circular arrows on your repository’s page

Installing Git on Your Own Computer

Go to http://git-scm.com/downloads and download the right version for your OS. Installing should be pretty simple. Afterwards, open up the Git GUI application (on OS X and Linux, you may have to go to the command line and use the command git gui).

Additionally, on OS X and Linux, instead of going to Repository→Git Bash as on Windows, you just type those same commands into the command line.

Common Problems

Git says I don’t have permission to push to origin

This problem is due to your origin having been incorrectly set. It can be remedied through the command:

  1. git remote set-url origin https://github.com/YOUR-USER-NAME-HERE/drugwars.git

Following this, attempt to push to origin and it should work.