Git 101

Git Workflow Components

• Working Directory: Your local workspace where you edit files. Changes here are not tracked until moved to the staging area.
• Staging Area: A prep zone for changes to be committed. You can selectively choose which changes to include in a commit.
• HEAD: The latest commit in the current branch, acting as a pointer to your most recent work.
• Local Repository: Your computer's storage for all your commits, branches, and the entire change history. It operates independently of network access.
• Remote Repository: A server-hosted repository (e.g., GitLab, GitHub) for code sharing and backup. It syncs with the local repository through push and pull commands.

Git File Status

Tracked vs Untracked Files

• Tracked files are those that Git knows about and has in its version history.
• Untracked files are new or unrecorded files in your working directory that Git isn't keeping track of yet; e.g. temp/, auto_settings.sav*, auto_positions.sav*, etc.

Staged vs Unstaged

• Staged files are those that have been marked for inclusion in the next commit, showing Git exactly what changes you want to commit.
• Unstaged files are the modified files in your working directory that have not been marked for the next commit yet.

Basic Commands Cheat Sheet

Syncing with Remote Repository

• To download updates from the remote repository without merging them:

$ git fetch

• To fetch changes from the remote repository and merge them into your current branch:

$ git pull

• To push local commits to the remote repository:

$ git push # pushes your commits to the remote repository

• To view the remote repository information:

$ git remote -v # lists the remote repositories and their URLs

Viewing Changes and Status

• To see the status of the working directory and staging area:

$ git status

• To list the commit history:

$ git log

• To view differences since the last commit:

$ git diff <file>

• To see tracked files:

$ git ls-files

Committing Changes

• To commit a single tracked file (file to staging area and commit changes in two steps):

$ git add <file>   
$ git commit -m 'commit message'  

• To commit all tracked files at once, use option -a (add to staging area and commit in a single step):

$ git commit -am 'commit message'

Ignoring Files

.gitignore lists files and folders to be ignored. To update the list, just use any file editor.

More details

Git Fetch vs. Git Pull

• git fetch is a command that downloads changes from a remote repository, but doesn't integrate any of these changes into your working files. It's essentially a safe way to review changes before integrating them into your local repository.

• git pull is a command that not only downloads changes from the remote repository but also immediately attempts to merge them into the branch you are currently working on. It is a combination of git fetch followed by git merge.

Git status explained

$ git status
On branch main
Your branch is up to date with 'origin/main'.

Changes to be committed:
  (use "git reset HEAD <file>..." to unstage)

        modified:   file1
        new file:   file2

Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git checkout -- <file>..." to discard changes in working directory)

        modified:   file3

Untracked files:
  (use "git add <file>..." to include in what will be committed)

        temp/
        notes.txt

• On Branch: You're currently on the main branch.
• Branch Status: Your main branch is up to date with origin/main (the main branch from the remote repository).
• Changes to be Committed:
  • file1 has been modified and file2 is a new file, both staged for the next commit.
  • To unstage, use git reset HEAD <file>.
• Changes Not Staged for Commit:
  • file3 is modified but not staged.
  • To stage, use git add <file>.
  • To discard changes, use git checkout -- <file>.
• Untracked Files:
  • temp/ and notes.txt are not tracked by Git.
  • To track, use git add <file>.
  • To ignore, add them to the .gitignore file

Your branch is ahead of 'origin/main'

$ git status
On branch main
Your branch is ahead of 'origin/main' by 3 commits.
  (use "git push" to publish your local commits)

nothing to commit, working tree clean

• On Branch: You're currently on the main branch.
• Branch Status:
  • Your main branch is ahead of origin/main by 3 commits. This means you have made commits locally that are not yet in the main branch on the remote repository.
  • To synchronize these changes with the remote repository, use git push.
• Working Tree Status:
  • Your working directory is clean, meaning there are no unstaged changes or untracked files.

Your branch is behind 'origin/main'

$ git status
On branch main
Your branch is behind 'origin/main' by 2 commits, and can be fast-forwarded.
  (use "git pull" to update your local branch)

nothing to commit, working tree clean

• On Branch: You're currently on the main branch.
• Branch Status:
  • Your main branch is behind origin/main by 2 commits. This indicates that there are updates on the remote repository that you don't have locally.
  • You can fast-forward your local branch to catch up with origin/main using git pull.
• Working Tree Status:
  • Your working directory is clean, meaning there are no unstaged changes or untracked files.

Basic Workflow Example

To add new files: $ git add <newfile>

To modify files: $ git add <modifiedfile>

To commit changes: $ git commit -m 'Description of changes'

To push to the remote repository: $ git push origin <branch>