Highlighting a .diff file

Question

Is there a way to highlight the syntax of a diff file (i.e. by using the listings package)?

Answer 1

You can just do this with the listings package, and you won't even need an external pre-processor. listings doesn't come with a diff style but you can define one like this:

\lstdefinelanguage{diff}{
  morecomment=[f][\color{blue}]{@@},     % group identifier
  morecomment=[f][\color{red}]-,         % deleted lines 
  morecomment=[f][\color{green}]+,       % added lines
  morecomment=[f][\color{magenta}]{---}, % Diff header lines (must appear after +,-)
  morecomment=[f][\color{magenta}]{+++},
}

Use it in the usual ways. E.g., \lstinputlisting[language=diff]{myfile.diff}.

Update: Diff viewers often highlight the background of lines, instead of coloring the text. This can be added with the help of Martin Scharrer's lstlinebgrd package, available on CTAN in his lstaddons bundle (or get the latest version from the package homepage)

Answer 2

minted?

\begin{minted}{diff}
<diff data goes here>
\end{minted}

would work, or

\inputminted{diff}{path/to/file.diff}

if you want to just read the diff from a file. Minted also provides a listing command you can use to wrap it in a floating box like a figure or table.

Answer 3

I extended the answer from alexis to cover more formats: normal format (diff), unified format (diff -u), context format (diff -c) and diffs from Git (git diff):

\lstdefinelanguage{diff}{
  sensitive=true,
  % diff command line
  morecomment=[f][\color{gray}][0]{diff},
  % commit identifiers for git diff
  morecomment=[f][\color{gray}][0]{index},
  % hunk location/line numbers for unified format
  morecomment=[f][\color{blue}][0]{@@},
  % hunk location/line numbers for context format
  morecomment=[f][\color{magenta}][0]{***},
  % changed line for context format
  morecomment=[f][\color{violet}][0]{!},
  % deleted lines for unified format
  morecomment=[f][\color{red!60!black}][0]-,
  % added lines for unified format
  morecomment=[f][\color{green!60!black}][0]+,
  % file name and time stamp old file
  morecomment=[f][\color{magenta}][0]{---},
  % file name and time stamp new file
  morecomment=[f][\color{magenta}][0]{+++},
  % Binary files ... differ
  morecomment=[f][\color{gray}][0]{Binary},
  % Only in ...: file.txt
  morecomment=[f][\color{gray}][0]{Only},
  % old mode ...
  morecomment=[f][\color{gray}][0]{old},
  % new mode ...
  morecomment=[f][\color{gray}][0]{new},
  % rename from/to ...
  morecomment=[f][\color{gray}][0]{rename},
  % similarity index ...%
  morecomment=[f][\color{gray}][0]{similarity},
  % deleted file mode ...%
  morecomment=[f][\color{gray}][0]{deleted},
  % hunk separator for context format
  morecomment=[f][\color{magenta}][0]{***************},
  % deleted lines for normal format
  morecomment=[f][\color{red!60!black}][0]<,
  % added lines for normal format
  morecomment=[f][\color{green!60!black}][0]>,
  % line number specifier for normal format
  morecomment=[f][\color{blue}][0]{0},
  % line number specifier for normal format
  morecomment=[f][\color{blue}][0]{1},
  % line number specifier for normal format
  morecomment=[f][\color{blue}][0]{2},
  % line number specifier for normal format
  morecomment=[f][\color{blue}][0]{3},
  % line number specifier for normal format
  morecomment=[f][\color{blue}][0]{4},
  % line number specifier for normal format
  morecomment=[f][\color{blue}][0]{5},
  % line number specifier for normal format
  morecomment=[f][\color{blue}][0]{6},
  % line number specifier for normal format
  morecomment=[f][\color{blue}][0]{7},
  % line number specifier for normal format
  morecomment=[f][\color{blue}][0]{8},
  % line number specifier for normal format
  morecomment=[f][\color{blue}][0]{9},
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