Day 23 - Advanced git

Spring 2023

Dr. Jared Joseph

Smith College

Overview

Timeline

git Recap
git in the Terminal
Advanced git
Advanced Github

Goal

Learn how to use git to effectively collaborate

git Recap

git as Timelines

The Turing Way

git Workflow

Key Terms

repo: Repository - the collection of git files that contain your project
commit: To save a checkpoint of your project for future reference
revert: Undo all changes made to a file since the last commit
staged: A file that is preparing to be commited, but has not yet been
push: To ‘push’ files from your local machine onto an internet service
pull: To ‘pull’ files from a remote service onto your machine
merge: To combine two branches/files of the same project
conflict: When two files or set of files have changes that cannot be easily merged
checkout: Load in a previous checkpoint (commit) or switch to a branch

git in the Terminal

git commands (but with words)

git add: Stage the file
git commit -m "<YOUR MESSAGE>": Commit staged files
git pull: Pull from GitHub
git push: Push files to GitHub

New git Commands

git status: Check the staging area and what branch you are on.

git log (pro-tip: git log --oneline --graph --decorate --all): Look at the history of past commits

git diff: Print the differences between the files as it is now and the most recent commit

git revert <FILES>: Undo all changes made to a file since the last commit

Advanced git

git Ignore

The hidden .gitignore file lets you tell git “I do not want you to pay attention to these files or folders.”

This can be very handy if you want to:

Ignore all .csv files
Ignore your scrap folder
Ignore the file containing your API keys
etc

Branches

branch ->

<- merge

git checkout <NAME OF BRANCH>: Switch between branches
git checkout -B <NAME OF BRANCH>: Create new branch and switch to it
git merge <NAME OF BRANCH>: Merge two branches

Advanced Github

Pull Requests

When you push a branch to GitHub, it will ask if you want to make a pull request to merge that branch into main.

Creating a request is the best way to merge your branches, as it allows you to use several powerful collaboration tools.

Pull Request Tools

Dealing with Conflict

Sometimes git/GitHub will tell you there is a conflict.

That’s not uncommon. It means two people worked on the same file and edited the same part of the code.

You need to tell git how to resolve the conflict by opening the file in question and committing the “real” version.

Turn this:

<<<<<<< HEAD

# read in data
read.csv("./data/my_csv.csv")

=======

# read in data using tidy nonsense
read_csv("./data/my_csv.csv")

>>>>>>> ee175895783b64e0e1f696d9456

Into this:

# final code
# read in data
read.csv("./data/my_csv.csv")

And commit then push.

Code Review

Code-Along

What is a Good Branch?

Getting a feel for how large the work done in a branch should be takes some practice. While I can’t give you a single answer, here are some guides to help.

Good Branches

Are topically coherent
Accomplish a single goal
Add a single feature to the project
Are closed once pulled into main

Bad Branches

Branches for each person on the team
Branches per day/week/time period
Combines multiple issues/tasks
Keeps getting re-used for new tasks

For Next Time

Topic

Package Documentation

To-Do

Finish Worksheet
READ: Function Documentation
READ: Other Markdown Files