Session 5: Branches

Track, organize and share your work: An introduction to Git for psychological research

Course at University of Hamburg

Slides | Source

Dr. Lennart Wittkuhn

lennart.wittkuhn@uni-hamburg.de

Konrad Pagenstedt

konrad.pagenstedt@uni-hamburg.de

May 06 2024 (12:15 pm)

Agenda

• 1 Last week: First steps with Git
• 2 Survey results
• 3 Today’s topic: Branches
• 4 GUIs

Schedule

No	Date	Title	Contents	Reading	Survey/Quiz
1	2024-04-08	Introduction to version control	Organisational matters Overview of seminar sessions Introduction to version control Introduction to Git and its advantages	Intro to version control	Course introduction Survey
2	2024-04-15	Command line	File Systems Benefits of the Command Line Basic Command Line commands	Command Line	Command Line Quiz
3	2024-04-22	Setup + Git Fundamentals	Installation and configuration of Git Initializing a Git repository Basic Git commands	Installation, Setup, First steps with Git	Installation Survey, Git Basics Quiz
4	2024-04-29	Basic Git workflow	Practicing basic Git commands Ignoring files with .gitignore Good commit messages	First steps with Git	Git Basics Quiz
5	2024-05-06	Git Branching and Merging	Understanding branches in Git Creating and switching between branches Merging branches Resolving merge conflicts	Branches	Git Branches Quiz
6	2024-05-13	Quarto Workshop	Introduction to Quarto
7	2024-05-20	Whit Monday	Cancelled
8	2024-05-27	Introduction to GitHub	Introduction to remote repositories Creating a GitHub account Creating and managing repositories on GitHub Pushing and pulling changes	GitHub Intro	GitHub Quiz
9	2024-06-03	GitHub with collaborators	Cloning a remote repository Branching and merging in a collaborative environment Pull Requests GitHub Issues Graphical User Interfaces (GUIs), e.g., GitKraken	GitHub Intro, GitHub Issues	GitHub Quiz
10	2024-06-10	GitHub with the world	Forking a remote repository README files Project Management	GitHub Intro, GitHub Issues	GitHub Quiz
11	2024-06-17	Repetition and Practice	Repetition and Practice
12	2024-06-24	Publishing	Creating Tags with Git Creating Releases with GitHub Using Zenodo for scientific publishing Licences Citation Files	Tags and Releases
13	2024-07-01	Graphical User Interfaces (cancelled)	Repetition and Practice Introduction to using GUIs	Graphical User Interfaces
14	2024-07-08	Summary & Wrap-Up	Course evaluation Repetition and Practice Introduction to using GUIs	Graphical User Interfaces

1 Last week: First steps with Git

Last week: First steps with Git

lennartwittkuhn.com/version-control-book/chapters/first-steps-git.html

Last week’s question: Saving command line history?

Use this:

history > history.txt

https://lennartwittkuhn.com/version-control-book/chapters/command-line.html#saving-command-line-history

Last week’s question: Commit .gitignore?

Yes, commit your project-specific .gitignore file.

https://lennartwittkuhn.com/version-control-book/chapters/first-steps-git.html#ignoring-files-and-folders-.gitignore

Last week’s learning objectives

Setup

💡 You know how to set up Git for the first time
💡 You have set up Git on your computer
💡 You understand the difference between the three Git configuration levels
💡 You know how to configure your username and email address in Git
💡 You have set up your preferred text editor when working with Git
💡 You can escape the command-line text editor Vim

First steps with Git

💡 You can initialize a Git repository
💡 You can stage and commit changes
💡 You know how to explore the commit history
💡 You can compare different commits
💡 You know how to use and create a .gitignore file
💡 You can discuss which files can (not) be tracked well with Git and why
💡 You know how to track empty folders in Git repositories

2 Survey results

Recap: Best practices for commit messages

• Try to keep commit messages short (less than 72 characters)
• Use present tense and start with an imperative verb to indicate the purpose of the commit, for example “add”, “fix”, “improve” (as if you are giving orders to the codebase to change its behavior)

If applied, this commit will … [your commit message]

• Try to describe why a change is being made
• Link specific issues that are addressed by your commit
• Use the description for more explanation and context

3 Today’s topic: Branches

Today’s topic: Branches

Figure 1: Image from Chapter “Git Branches” of the “The Turing Way handbook to reproducible, ethical and collaborative data science”, used under a Creative Commons Attribution 4.0 License.

Illustration of branches in a Git repository. Each circle represents a commit. Commits on the Main branch are shown in gray. The branch Feature A (blue circles) was created from the Main branch and later merged again. In-between, another branch Feature A-1 was created from the Feature A branch (green circles) and merged with that branch again before the Feature A branch was eventually merged with the Main branch. The branch Feature B was created but abandoned and not merged with the Main branch.

Today’s chapter

https://lennartwittkuhn.com/version-control-book/chapters/branches.html

This weeks learning objectives

💡 You understand the purpose and benefits of using branches in Git
💡 You can create and switch between branches
💡 You can merge branches and resolve merge conflicts
💡 You can name at least three best practices when working with branches

Your turn

1. Content Review: Read the chapter “Branches” in the Version Control Book.
2. Implementation: Try out the commands in the chapter! Play around! Have fun!
3. Note: We will do the implementation exercises in class together, step-by-step.
4. Exercises: Complete the exercises in the survey.

Ask questions!

Let’s git started!

and branch out

Implementation Exercises

1. Create and merge a branch

1. Create a new branch called feature.
2. Switch to your new branch.
3. Add a new recipe to your recipes text file.
4. Switch back to the default branch (main or master).
5. Merge the feature branch with your default branch and delete the feature branch afterwards.

2. Create and resolve a merge conflict

Deliberately create a merge conflict by editing the same section of a file on two separate branches and attempting to merge them. An example can be found in the Version Control Book chapter. Resolve the merge conflict and delete the feature branch afterwards.

3. Complete the branches quiz

4 GUIs

GUIs

lennartwittkuhn.com/version-control-book/chapters/gui.html