README.md

Short git command-line usage summary

A small collection of most frequentely used git commands for your day-to-day work and common tasks.

Jargon terms

master => THE main branch, should always represent the stable version of the project

remote => a branch on the GitHub remote server

origin => misleading term, it's just the default alias for the address of the remote repository, i.e. https://github.com/lpacher/lae.git. This URL is returned by git config --get remote.origin.url

General usage

% git <command> [options] [target]

Command help

Short help:

% git <command> -h 

Complete manual page:

% git <command> --help

Example:

% git clone -h
% git clone --help

Git configuration

Some useful aliases and configurations:

% git config --global alias.root "rev-parse --show-toplevel"    # create a "git root" alias to easily locate the Git top-level directory
% git config --global alias.co 'checkout'                       # allows to use "git co" instead of "git checkout"
% git config color.ui true                                      # enable better display with colors

Repository download

% cd Desktop
% git clone https://github.com/lpacher/lae.git [target directory]

NOTE: This is equivalent to:

% cd Desktop
% mkdir lae (or mkdir <target directory>)
% cd lae
% git init
% git remote add origin https://github.com/lpacher/lae.git
% git pull origin master

List all available branches on remote server

There are many different commands for this:

% git branch --remote

or

% git remote show origin

or

% git ls-remote

WARNING: Always fetch latest updates from the remote server with git fetch before running these commands, otherwise new branches created on the server will not be listed.

Checkout an existing branch

% git checkout <branch name>

WARNING: Be sure to commit all your local changes to tracked files before changing working branch !

Display a list of all checked-out branches

% git branch

NOTE: The * indicates the current working branch.

Changing working branch

% git checkout <branch name>

Display commits history (log file)

% git log [with many options available]

Display working branch status

This shows you all modified files, committed files and untracked files:

% git status [--verbose]

Fetching

Retrieve all updates (commits and new branches) published by other people into the remote server:

% git fetch

Use instead

% git fetch origin <branchName>

to fetch only from the specified branch.

NOTE: Fetching from a repository grabs all the new remote-tracking branches and tags without merging those changes into your own branches.

Stage and commit

% git add /path/to/filename1
% git add /path/to/filename2
% git add /path/to/filename3
% git commit -m "Commit message for those 3 modified files"
% git add /path/to/filename4
% git commit -m "Commit message for the 4th modified file"

NOTE: You can add as many commits as you wants, also multiple-commits on the same file for different changes. All commits will be pushed into remote repository after a git push.

Undo a git add (i.e. remove files staged for a git commit)

% git reset /path/to/filename

To undo git add . use instead

% git reset

without the dot.

Discard changes to a file in working directory

% git checkout -- /path/to/filename

Edit the commit messagge

In case your last-commit message contains typos/missing information and thus requires changes you can amend it :

% git commit --amend

Then enter the new commit messagge.

Adding more changes to your last commit

In case you already issued a git commit but you want to add modified file(s) to the last commit :

% git add /path/to/filename [/path/to/another/filename]
% git commit --amend

If you don't want to change your commit message, you can run the --amend command with the --no-edit flag :

% git commit --amend --no-edit

Pushing an amended commit

% git push -f origin <branchName>

Renaming files and directories

% git mv oldFileName newFileName
% git commit -m "Why you changed the file name"

WARNING: DO NOT USE a standard UNIX mv on tracked files !

Deleting files and directories

% git rm /path/to/filename
% git rm -r /path/to/directory
% git commit -m "Why you removed the file/directory"

WARNING: DO NOT USE a standard UNIX rm on tracked files !

Merging from other branches

% git pull origin <branchName>

This is equivalent to:

% git fetch
% git merge

Resolve merge conflicts

Git is smart-enough to try to merge all non-conflicting differences seen in a file that has been modified both by you and by someone else. However, in case of a merge conflict you have to fix it yourself. To do this, open the file/files for editing and manually fix conflicts enclosed between

<<<<<<< HEAD
Local version of the code creating the conflict
=======
Remote version of the code creating the conflict
>>>>>>> [other/branch/name]

After having fixed all conflicting lines, save the file and perform a git commit to mark the conflict as resolved.

NOTE: There are also many text-based and GUI-based merging tools. Just call git mergetool after having configured the tool to be used, e.g.

% git config --global merge.tool vimdiff

Uploading changes to the remote server

% git push origin <branch name>

Rename a branch

To rename a branch, either use :

% git branch -m <newBranchName>    # inside the branch you want to rename

or

% git branch -m <branchName> <newBranchName>  # from any other different branch

To push this branch-renaming to the remote server, then use :

% git push origin :<oldBranchName> <newBranchName>
% git push origin -u <newBranchName>

Delete feature branches (both local and remote)

% git checkout devel
% git branch -d <branchName>                   # removes your LOCAL branch <branchName>
% git push origin --delete <branchName>        # removes the REMOTE branch <branchName>

WARN: You cannot delete a checked-out branch ! Change working branch before deleting your feature branch.

Tag master releases

% git checkout master
% git pull origin devel
% git push origin master
% git tag -a <tagName> -m "Tag message"
% git push origin <tagName>