John's GitHub page

OK. Hi there. I'm John. So recently I've made some modifications to code that is hosted on GitHub, as you can see in my account. I'm new and still learning the process, so here's what I've figured out:

Hard reset to specific commit

You can use `git log --stat` to find a specific commit hash, then

Reset the branch to the specific commit:

git reset --hard abc1234

Push the changes to the remote repository:

git push origin main --force

Configure new GitHub repository

Create a new repository on the command line

echo "# just-testing" >> README.md
git init
git add README.md
git commit -m "first commit"
git branch -M main
git remote add origin git@github.com:jj5/just-testing.git
git push -u origin main

Push an existing repository from the command line

git remote add origin git@github.com:jj5/just-testing.git
git branch -M main
git push -u origin main

Configure your user

git config --global user.name "John Elliot V"
git config --global user.email jj5@jj5.net

Configuring an editor

git config --global core.editor vim

View all of your configuration settings

This command also shows where the config settings come from:

git config --list --show-origin

Creating a repo

git config --global init.defaultBranch v0.1
cd /var/git
git init --bare my-repo.git
cd my-repo.git
git branch -m v0.1

Get info about your upstream remote origin

The following command is similar to svn info:

$ git remote show origin

Revert local changes

See here:

If you want to revert changes made to your working copy, do this:

git checkout .

If you want to revert changes made to the index (i.e., that you have added), do this. Warning this will reset all of your unpushed commits to master!:

git reset

If you want to revert a change that you have committed, do this:

git revert <commit 1> <commit 2>

If you want to remove untracked files (e.g., new files, generated files):

git clean -f

Or untracked directories (e.g., new or automatically generated directories):

git clean -fd

Configure your upstream remote

# list current remotes:
$ git remote -v

# add an upstream remote if there isn't one:
$ git remote add upstream git@github.com/orig-owner/orig-repo.git

# verify your remotes contains your new remote:
$ git remote -v

Syncing a fork (rebase method)

Be sure to configure your upstream remote first.

# ensure your copy of upstream is fully up-to-date
$ git fetch upstream

# ensure that you are on your topic branch
$ git checkout topic-branch

# this removes your commits, pushes in the commits from upstream added since
# you forked and branched, and then re-adds your commits
$ git rebase upstream/master 

# now fix any conflicts that couldn't be merged automatically
# (which might warrant its own section)

At this point your topic branch is up to date with the latest upstream changes, so you can push the topic branch back up to your origin (you will likely need to `git push -f` because your rebase has rewritten history) and create the PR.

Syncing a fork (merge method)

Be sure to configure your upstream remote first.

# fetch branches/commits from upstream repository:
$ git fetch upstream

# switch to your fork's local master:
$ git checkout master

# merge upstream/master to local master:
$ git merge upstream/master

# push your local master back to your fork on GitHub:
$ git push origin

Submitting a patch via GitHub

Fork the upstream repository into a project in your account

1. go to GitHub
2. login
3. navigate to the project repository you want to fork
4. click 'Fork' on the top right

Clone your fork

1. open a terminal on your workstation
2. change dir to your github directory (I use /home/jj5/repo/git/github/jj5)
3. clone your fork (using SSH) with: git clone git@github.com/jj5/MyProject.git

Make a topic branch in your fork

You can read about what a topic branch is.

1. open a terminal on your workstation
2. change dir to your github fork (e.g. /home/jj5/repo/git/github/jj5/MyProject)
3. create a branch with: git branch branch-name
4. switch to your new branch: git checkout branch-name

Note: you can create a branch and check it out with one command: git checkout -b branch-name

Make your changes

So edit files, add files, etc.

Tell git about new files

If you've added files include them in git with: git add file.name

Commit your changes on the topic branch

To commit your changes: git commit -a -m 'What you did...'

Push your changes into your fork at GitHub

To push your topic branch upstream: git push --set-upstream origin branch-name

Create a pull request

1. go to GitHub
2. login
3. navigate to your fork in your account
4. in the top left select your topic branch for the Branch drop down
5. click 'New pull request'
6. the 'base fork' should be the project you forked from that you wish to contribute to
7. the 'base' branch is the branch you want to merge with (probably 'master'?)
8. the 'head fork' is where your proposed changes are (i.e. in your fork)
9. the 'compare' branch is the branch that has your changes (i.e. your topic branch)
10. add a message, check your changes, and submit your way to victory!

Links

• 99% of the Git commands you'll need at work, demonstrated in a single script
• Configuring a remote for a fork
• Syncing a fork
• What is a git topic branch?
• Creating a pull request
• Creating a pull request from a fork

Tools

Git

So the git command-line tool is pretty much essential. Install on Debian with:

# apt-get install git

SourceTree

SourceTree comes recommended as a GUI for beginners and pros alike. Install on Debian with: oh, dear. It's not a Linux tool. Nevermind.

GitEye

GitEye is a git GUI recommended by Jedd. It's beer free rather than speech free. The download page is here.