basics.tex

\documentclass[slidestop]{beamer}

\input{../shared/shared.tex}

\author{Jeroen F.J. Laros}
\title{\courseTitle}
\providecommand{\mySubTitle}{Git Basics}
\providecommand{\myConference}{\courseTitle}
\providecommand{\myGroup}{}
\providecommand{\myDepartment}{Department of Human Genetics}
\providecommand{\myCenter}{Center for Human and Clinical Genetics}

\usetheme{lumc}

\begin{document}

% This disables the \pause command, handy in the editing phase.
%\renewcommand{\pause}{}

% Make the title slide.
\makeTitleSlide{\includegraphics[width=3.5cm]{git_logo}}

% First page of the presentation.
\section{Initialisation}
\subsection{Starting a project}
\begin{pframe}
  Creating a new repository is easy. You do not need a server, no registration,
  etc.
  \begin{lstlisting}[language=none, caption=Make a new repository.]
    $ cd ~/projects
    $ git init
    Initialized empty Git repository in <path>/.git/
  \end{lstlisting}
  \pause

  Or you can ``clone'' an existing repository.
  \begin{lstlisting}[language=none, caption=Clone an existing repository.]
    $ git clone <path-to-repository>
  \end{lstlisting}
\end{pframe}

\begin{pframe}
  You can see a hidden directory in a Git repository.
  \begin{lstlisting}[language=none, caption=A hidden directory is added.]
    $ ls -a
    .  ..  .git
  \end{lstlisting}

  This directory contains almost everything that Git stores and manipulates.
\end{pframe}

\section{Manipulation}
\subsection{Local operations}
\begin{pframe}
  \begin{figure}[]
    \begin{center}
      \includegraphics[height=0.7\textheight]{18333fig0106-tn}
    \end{center}
    \caption{Working directory, staging area, and Git directory.}
  \end{figure}
\end{pframe}

\subsection{Checking the status of your files}
\begin{pframe}
  \begin{lstlisting}[language=none, caption=Check status.]
    $ git status
    nothing to commit (working directory clean)
  \end{lstlisting}

  ``\lstinline{git status}'' can tell you whether your files are:
  \begin{itemize}
    \item Untracked.
    \item Unmodified.
    \item Modified.
    \item Staged.
  \end{itemize}
\end{pframe}

\begin{pframe}
  \begin{figure}[]
    \begin{center}
      \includegraphics[height=0.7\textheight]{18333fig0201-tn}
    \end{center}
    \caption{The lifecycle of the status of your files.}
  \end{figure}
\end{pframe}

\subsection{Adding, removing, renaming}
\begin{pframe}
  \begin{lstlisting}[language=none, caption=This file is not tracked.]
    $ echo First version. > README
    $ git status
    # Untracked files:
    #       README
  \end{lstlisting}
  \pause

  \begin{lstlisting}[language=none, caption=Now the file will be tracked.]
    $ git add README
    $ git status
    # Changes to be committed:
    #       new file:   README
  \end{lstlisting}

  To rename a file, use ``\lstinline{git mv}'', to remove, use
  ``\lstinline{git rm}''.
\end{pframe}

\section{Working with versions}
\subsection{commit}
\begin{pframe}
  Once you have modified your files and added them to the \emph{staging area},
  you can commit them (add them to the repository).
  \begin{lstlisting}[language=none, caption=Commit a new version.]
    $ git commit
  \end{lstlisting}

  This will open an editor, give a short description (50 characters) and a list
  of the changes (72 column format).
  \begin{itemize}
    \item Useful when you want to search.
  \end{itemize}
  \pause

  \begin{lstlisting}[language=none, caption=Commit a new version.]
    $ git commit -m "Solved the counting bug."
  \end{lstlisting}
\end{pframe}

\subsection{Undoing changes}
\begin{pframe}
  Sometimes you will accidentally add a file.
  \begin{lstlisting}[language=none, caption=Adding a new version of a file.]
    $ echo Second version. > README
    $ git add README
    $ git status
    # Changes to be committed:
    #       modified:   README
  \end{lstlisting}
  \pause

  If you want to undo this, you can use ``\lstinline{git reset}''.
  \begin{lstlisting}[language=none, caption=Unstage a file.]
    $ git reset README
    $ git status
    # Changes not staged for commit:
    #       modified:   README
  \end{lstlisting}
\end{pframe}

\begin{pframe}
  Keep in mind that ``\lstinline{git reset}'' by default sets a staged file
  back to unstaged.
  \begin{lstlisting}[language=none, caption=Unstage a file.]
    $ git reset README
    $ git status
    # Changes not staged for commit:
    #       modified:   README
  \end{lstlisting}
  \pause

  To discard all changes in an unstaged file, you can use
  ``\lstinline{git checkout}''
  \begin{lstlisting}[language=none, caption=Discarding changes.]
    $ git checkout -- .
    $ git status
    nothing to commit, working directory clean
  \end{lstlisting}
\end{pframe}

\begin{pframe}
  For now, let's commit our change and move on.
  \begin{lstlisting}[language=none, caption=Adding a new version of a file.]
    $ echo Second version. > README
    $ git commit
    $ git status
    nothing to commit, working directory clean
  \end{lstlisting}
\end{pframe}

\subsection{Viewing the history}
\begin{pframe}
  To see the history of your project, use ``\lstinline{git log}''.
  \begin{lstlisting}[language=none, caption=The log of our project.]
    $ git log
    commit cc61ee7cd72590f3bebcc9e1ff3e9435c7f7dd28
    Author: J.F.J. Laros <j.f.j.laros@lumc.nl>
    Date:   Fri Oct 11 14:18:13 2013 +0200

        Second version.

    commit 8e10be812fd78f69a5e3bac7670c62438161b6b0
    Author: J.F.J. Laros <j.f.j.laros@lumc.nl>
    Date:   Fri Oct 11 14:17:51 2013 +0200

        First version.
  \end{lstlisting}
\end{pframe}

\subsection{Undo a commit}
\begin{pframe}
  Sometimes we want to undo an entire commit. This is done with
  ``\lstinline{git revert}''.
  \begin{lstlisting}[language=none, caption=Revert a commit.]
    $ git revert cc61ee7cd7
    $ cat README
    First version.
  \end{lstlisting}

  The hash can be found with ``\lstinline{git log}''.
  \bigskip
  \pause

  You can also use a unique prefix of this hash, usually six characters is
  enough.
\end{pframe}

\subsection{Viewing changes in detail}
\begin{pframe}
  If you want to see what has changed, use ``\lstinline{git diff}''.
  \begin{lstlisting}[language=none, caption=Difference between the working copy
    and the staging area.]
    $ echo Third version. > README
    $ git diff
    --- a/README
    +++ b/README
    @@ -1 +1 @@
    -First version.
    +Third version.
  \end{lstlisting}
  \pause

  For staged files, use the ``\lstinline{--cached}'' or
  ``\lstinline{--staged}'' option.
  \begin{lstlisting}[language=none, caption=Difference between the staging area
    and the last commit.]
    $ git diff --cached
  \end{lstlisting}
\end{pframe}

\begin{pframe}
  You can see the differences between any two versions.
  \begin{lstlisting}[language=none, caption=Difference between the working copy
    and an other commit.]
    $ git diff cc61ee
    --- a/README
    +++ b/README
    @@ -1 +1 @@
    -Second version.
    +Third version.
  \end{lstlisting}
  \pause

  \begin{lstlisting}[language=none, caption=Difference between two committed
    versions.]
    $ git diff 8e10be cc61ee
  \end{lstlisting}
\end{pframe}

\section{Extras}
\subsection{Explicit no tracking}
\begin{pframe}
  Sometimes you do not want to track certain files:
  \begin{itemize}
    \item Executables.
    \item PDF files (if you still have the \LaTeX\ source).
    \item Python bytecode (\lstinline{.pyc}) files.
    \item Files containing passwords.
  \end{itemize}
  \medskip
  \pause

  Use the special ``\lstinline{.gitignore}'' file.
  \begin{lstlisting}[language=none, caption=Ignoring certain files.]
    $ touch notrack.txt
    $ echo notrack.txt > .gitignore
    $ git add .gitignore
    $ git commit
    $ git status
    nothing to commit, working directory clean
  \end{lstlisting}
\end{pframe}

\subsection{Help}
\begin{pframe}
  With the ``\lstinline{help}'' command get the manual of a particular
  subcommand.
  \begin{lstlisting}[language=none, caption=Get the full manual.]
    $ git help <command>
  \end{lstlisting}
  \pause

  Example.
  \begin{lstlisting}[language=none, caption=Get the manual for the diff
    subcommand.]
    $ git help diff
  \end{lstlisting}
\end{pframe}

\makeAcknowledgementsSlide{
  \begin{tabular}{l}
    \acknowledgements
  \end{tabular}
  \bigskip

  \hfill\includegraphics[width=3.5cm]{git_logo}

  \begin{tabular}{l}
    \small\url{http://git-scm.com/book}\\
  \end{tabular}
}

\end{document}