Git Version Control: Setup and Configuration

Overview

• Git is a free, open-source, distributed version control system.
• It manages everything GitHub-related locally on a computer.
• Git commands for easy reference are featured.

Installation and GUIs

• Platform-specific installers are available for Git.
• GitHub provides updates to the command-line tool.
• It provides a GUI for interaction, review, and repository synchronization.
• GitHub is available for Windows, Mac, Linux, and Solaris platforms.

Setup

• User information is configured across all local repositories.
• git config --global user.name "[firstname lastname]" sets a name identifiable for credit when reviewing version history.
• git config --global user.email "[valid-email]" sets an email address associated with each history marker.
• git config --global color.ui auto sets automatic command line coloring for easy reviewing.

Setup and Init

• User information is configured, initializing and cloning repositories.
• git init initializes an existing directory as a Git repository.
• git clone [url] retrieves an entire repository from a hosted location via URL.

Stage and Snapshot

• This involves working with snapshots and the Git staging area.
• git status shows modified files in the working directory, staged for the next commit.
• git add [file] adds a file to the next commit (stage).
• git reset [file] unstages a file while retaining changes in the working directory.
• git diff shows the difference between what is changed but not staged.
• git diff --staged shows the difference of what is staged but not yet committed.
• git commit -m "[descriptive message]" commits staged content as a new commit snapshot.

Branch and Merge

• This involves isolating work in branches, changing context, and integrating changes.
• git branch lists branches; an asterisk appears next to the currently active branch.
• git branch [branch-name] creates a new branch at the current commit.
• git checkout switches to another branch and checks it out into the working directory.
• git merge [branch] merges the specified branch's history into the current branch.
• git log shows all commits in the current branch's history.

Inspect and Compare

• Examining logs, diffs, and object information happens in this stage.
• git log shows the commit history for the currently active branch.
• git log branchB..branchA shows commits on branch A that are not on branch B.
• git log --follow [file] shows the commits that changed a file, even across renames.
• git diff branchB...branchA shows the difference of what is in branch A that is not in branch B.
• git show [SHA] shows any object in Git in human-readable format.

Share and Update

• This involves retrieving updates from another repository and updating local repos.
• git remote add [alias] [url] adds a Git URL as an alias.
• git fetch [alias] fetches all the branches from that Git remote.
• git merge [alias]/[branch] merges a remote branch into the current branch to bring it up to date.
• git push [alias] [branch] transmits local branch commits to the remote repository branch.
• git pull fetches and merges any commits from the tracking remote branch.

Tracking Path Changes

• This section covers versioning file removes and path changes.
• git rm [file] deletes the file from the project and stages the removal for commit.
• git mv [existing-path] [new-path] changes an existing file path and stages the move.
• git log --stat -M shows all commit logs with an indication of any paths that moved.

Ignoring Patterns

• This involves preventing unintentional staging or committing of files.
• Save a file with desired patterns as .gitignore with either direct string matches or wildcard globs.
• git config --global core.excludesfile [file] creates a system-wide ignore pattern for all local repositories.

Rewrite History

• This section covers rewriting branches, updating commits, and clearing history.
• git rebase [branch] applies any commits of the current branch ahead of the specified one.
• git reset --hard [commit] clears the staging area and rewrites the working tree from the specified commit.

Temporary Commits

• This involves temporarily storing modified, tracked files in order to change branches.
• git stash saves modified and staged changes.
• git stash list lists stack-order of stashed file changes.
• git stash pop writes working from the top of the stash stack.
• git stash drop discards the changes from the top of the stash stack.