GitTeX

How to use Git version control info in LaTeX

Preliminary setup

Create once and for all a git tex alias by running the following command from inside your git repository:

git config alias.tex "log -1 --pretty=format:'\newcommand*{\gitdate}{%ad}%n\newcommand*{\githash}{\texttt{%h}}%n\newcommand*{\gitrefnames}{{\scriptsize\texttt{%d}}}%n'"

If you want to have the alias available everywhere on your local machine, use the --global flag:

git config --global alias.tex "log -1 --pretty=format:'\newcommand*{\gitdate}{%ad}%n\newcommand*{\githash}{\texttt{%h}}%n\newcommand*{\gitrefnames}{{\scriptsize\texttt{%d}}}%n'"

Alternatively, you could add the following lines to your .git/config or $HOME/.gitconfig file:

[alias]
        tex = log -1 --pretty=format:'\newcommand*{\gitdate}{%ad}%n\newcommand*{\githash}{\texttt{%h}}%n\newcommand*{\gitrefnames}{{\scriptsize\texttt{%d}}}%n'

Then invoking git tex produces an output like this:

\newcommand*{\gitdate}{Fri Jul 22 10:55:58 2016 -0400}
\newcommand*{\githash}{\texttt{a0155de}}
\newcommand*{\gitrefnames}{{\scriptsize\texttt{ (HEAD -> master, github/master)}}}

(You can use options like git tex --date=short and git tex --decorate=full, too.)

LaTeX files

Add the following lines to the preamble of your LaTeX file:

% see github.com/mava/GitTeX
\immediate\write18{git tex > \jobname.gtx}
\InputIfFileExists{\jobname.gtx}{}{}
\providecommand*{\gitdate}{\today}
\providecommand*{\githash}{info not available}
\providecommand*{\gitrefnames}{}

If git tex ran successfully then:

\gitdate = author date (format respects --date= option)
\githash = abbreviated commit hash
\gitrefnames = ref names, like the --decorate option of git log (format respects --decorate= option)

otherwise:

\gitdate = \today
\githash = info not available
\gitrefnames = empty string

(or whatever you specified in the \providecommands above).

These commands could then be used as follows, for example:

\date{\gitdate, revision \githash\gitrefnames}

You need to invoke (pdf)latex --shell-escape or to enable shell escape globally, for example by running tlmgr conf texmf shell_escape t.

Oddly enough, if shell escape is only enabled partially (set to p) then adding git to shell_escape_commands does not work, and running (pdf)latex produces the following error message:

fatal: ambiguous argument '>': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'