dAlembertGitTutorial

Interactive tutorial

Getting started with git

Make a project directory

• pwd
• mkdir myTestRepo
• cd myTestRepo.

Initialize a repo

• git init
• ls -a: presence of .git

Add content

• vi hello.sh - Open a new file in vi (or vim) named hello.sh.
• i - Enter “Insert” mode.
• Type (or copy/paste, if your terminal supports that):

    #!/bin/bash
    echo "Hello world"
  

• Esc - Leave “Insert” mode.
• :wq, Enter - Issue the command “Write, then quit.”
• chmod +x hello.sh
• ./hello.sh

See what git sees

• git status: “untracked”

Stage files to be added / updated

git add hello.sh

Other wildcards:

• *.txt - nonrecursive
• \*.txt - subdir recursive
• git add -A - match working directory

Ignore files

• .gitignore

Take a snapshot

• git status
• git commit -m "Initial commit."

Make a change

• vi hello.sh - Open the editor.
• j - We’re in command mode, so this doesn’t insert a character, but instead moves the cursor down a line.
• llllllllllllllllll - Move the cursor between d and ". If you overshoot, you can press h as many times as you need to go back the other way.
• i - Enter insert mode.
• , I can use git! - Enter some text.
• Esc, :wq, Enter - Return to command mode, save, and quit, as before.

Test it and see what changed

• ./hello.sh
• git status
• git diff --word-diff hello.sh

Snapshot

• git commit -a -m "Add qualifications.".

History and ancestor comparisons

• git log
• git diff --word-diff HEAD~ HEAD hello.sh
  • HEAD~~~: “the parent of the parent of the parent of HEAD”
  • HEAD~4
  • HEAD@{yesterday}
  • 1c002d as shorthand for 1c002dd4b536e7479fe34593e72e6c6c1819e53b

Going back in time

DANGER ALERT: If you have uncommitted changes in your working directory, the following commands can destroy them, leading to lost work. Make sure you git status to make sure your working directory is clean!

• git checkout HEAD~
  • 'detached HEAD' state
• cat hello.sh
• git checkout master.

Reverting a change

• git revert HEAD: add a new commit “reversing” the last one

Working with remote repos

Adding a remote and pushing

Make a new bare repo on GitHub

• “New repository” -> myTestRepo
• git remote add origin https://github.com/Username/myTestRepo.git
• `git push -u origin master*
• https://github.com/Username/myTestRepo.

Make a change and send to remote

• git push origin master

Pulling from a remote

• Check: git fetch
• Download: git pull

Initializing a repo from a remote

• git clone

What is this webpage?

This page was automagically generated by GitHub Pages from a repo that you can find here. You can see the license for this page below.

Collaboration

Branches

• git checkout -b <branchname>
• git reflog
• Switching: git checkout <branchname>

GitHub “Fork and Pull” Model

We’ll do this live!

License

This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.