Week 17: A Deeper Look at Git

Week	Topic	Learning Objectives	Key Resources
17	A Deeper Look at Git	Students will be abel to develop a better understanding of git version control and command usage in the command line.	Week 17 Slides TBD

Overview

Git Branching

What are Git branches?

• Pointers to a snapshot of changes
• Used to add new features or fix bugs in isolation
• Keeps the main branch free from questionable code
• Lightweight compared to other VCS models

How Git branches work

• Represent an independent line of development
• Abstraction for the edit/stage/commit process
• New commits are recorded in the history for the current branch
• Tightly integrated with git checkout and git merge commands

Common options

• git branch: List all branches
• git branch <branch>: Create a new branch
• git branch -d <branch>: Delete a branch (safe operation)
• git branch -D <branch>: Force delete a branch (even with unmerged changes)
• git branch -m <branch>: Rename the current branch
• git branch -a: List all remote branches

Creating branches

• Branches are pointers to commits
• Creating a branch does not change the repository, only creates a new pointer

Creating remote branches

• Configure and add a remote repo to the local repo config
• Push a copy of the local branch to the remote repo

Deleting branches

• Delete a branch after merging it into the main code base
• Use -d flag for safe deletion (prevents deleting unmerged branches)
• Use -D flag to force delete a branch (be cautious)
• To delete a remote branch, use git push origin --delete <branch> or git push origin :<branch>

Git Merge

How it works

• Combines multiple sequences of commits into one unified history
• Finds a common base commit between the branches
• Creates a new "merge commit" that combines the changes of each queued merge commit sequence

Preparing to merge

• Confirm the receiving branch with git status and git checkout
• Fetch the latest remote commits with git fetch and git pull

Merging

• Execute git merge <branch> to merge <branch> into the current branch

Fast-forward merge

• Occurs when there is a linear path from the current branch to the target branch
• Git moves the current branch pointer to the target branch tip
• No new commit is created

3-way merge

• Occurs when the branches have diverged
• Uses a dedicated commit to tie together the two histories
• Useful for integrating longer-running features

Resolving conflicts

• Occurs when both branches have changed the same part of the same file
• Git stops before the merge commit and asks for manual resolution
• Conflicts are marked with <<<<<<<, =======, and >>>>>>>
• Resolve conflicts by editing the affected files and staging them with git add
• Commit the changes to complete the merge

Assignment Rubric

See final project rubric.