Syntax Coloring of Source Code

Trac supports language-specific syntax highlighting of source code within wiki formatted text in wiki processors blocks and in the repository browser.

To do this, Trac uses external libraries with support for a great number of programming languages.

Currently Trac supports syntax coloring using one or more of the following packages:

• ​Pygments, by far the preferred system, as it covers a wide range of programming languages and other structured texts and is actively supported
• ​GNU Enscript, commonly available on Unix but somewhat unsupported on Windows (use is deprecated)
• ​SilverCity, legacy system, some versions can be problematic (use is deprecated)

To activate syntax coloring, simply install either one (or more) of these packages (see #ExtraSoftware section below). If none of these packages is available, Trac will display the data as plain text.

About Pygments

​Pygments is a highlighting library implemented in pure python, very fast, easy to extend and ​well documented.

The Pygments default style can specified in the mime-viewer section of trac.ini. The default style can be overridden by setting a Style preference on the preferences page.

It's very likely that the list below is outdated because the list of supported pygments lexers is growing weekly. Just have a look at the page of ​supported lexers on the pygments webpage.

Syntax Coloring Support

Known MIME Types

MIME Types	WikiProcessors
application/javascript	js
application/msword	doc dot
application/pdf	pdf
application/postscript	ps
application/rss+xml	rss
application/rtf	rtf
application/x-csh	csh
application/x-dos-batch	bat batch cmd dos
application/x-genshi	genshi
application/x-sh	sh
application/x-troff	nroff roff troff
application/x-yaml	yaml yml
application/xsl+xml	xsl
application/xslt+xml	xslt
image/svg+xml	svg
image/x-icon	ico
model/vrml	vrml wrl
text/css	css
text/html	htm html
text/html+jinja	jinja
text/plain	AUTHORS COPYING ChangeLog INSTALL README RELEASE TXT text txt
text/x-ada	ada adb ads
text/x-apacheconf	apache apacheconf
text/x-asm	asm
text/x-asp	asp
text/x-awk	awk
text/x-c++hdr	H HH c++hdr hh hpp
text/x-c++src	C C++ CC c++ c++src cc cpp
text/x-chdr	chdr h
text/x-csharp	C# c# cs csharp
text/x-csrc	c csrc xs
text/x-diff	diff patch
text/x-dylan	dylan
text/x-eiffel	e eiffel
text/x-elisp	el elisp
text/x-fortran	f fortran
text/x-haskell	haskell hs
text/x-idl	ice idl
text/x-inf	inf
text/x-ini	cfg ini
text/x-java	java
text/x-ksh	ksh
text/x-lua	lua
text/x-m4	m4
text/x-mail	mail
text/x-makefile	GNUMakefile Makefile make makefile mk
text/x-nginx-conf	nginx nginx-conf
text/x-objc	m mm objc
text/x-ocaml	ml mli ocaml
text/x-pascal	pas pascal
text/x-perl	PL perl pl pm
text/x-php	php php3 php4
text/x-psp	psp
text/x-pyrex	pyrex pyx
text/x-python	py python
text/x-python-doctest	pycon python-doctest
text/x-rfc	rfc
text/x-rst	rst
text/x-ruby	rb ruby
text/x-scheme	scheme scm
text/x-sql	sql
text/x-tcl	tcl
text/x-tex	tex
text/x-textile	textile txtl
text/x-vba	bas vb vba
text/x-verilog	v verilog
text/x-vhdl	vhd vhdl
text/x-zsh	zsh
text/xml	xml

Note that the rich content may be directly rendered instead of syntax highlighted. This usually depends on which auxiliary packages are installed and on which components are activated in your setup. For example a text/x-rst document will be rendered via docutils if it is installed and the trac.mimeview.rst.ReStructuredTextRenderer is not disabled, and will be syntax highlighted otherwise.

In a similar way, a document with the mimetype text/x-trac-wiki is rendered using the Trac wiki formatter, unless the trac.mimeview.api.WikiTextRenderer component is disabled.

HTML documents are directly rendered only if the render_unsafe_html settings are enabled in the TracIni (those settings are present in multiple sections, as there are different security concerns depending where the document comes from). If you want to ensure that an HTML document gets syntax highlighted and not rendered, use the text/xml mimetype.

If a mimetype property such as 'svn:mime-type' is set to 'text/plain', there is no coloring even if file is known type like 'java'.

List of Languages Supported, by Highlighter

This list is only indicative.

	SilverCity	Enscript	Pygments
Ada		✓
Asm		✓
Apache Conf			✓
ASP	✓	✓
C	✓	✓	✓
C#		✓ (1)	✓
C++	✓	✓	✓
CMake	?	?	✓
Java	✓ (2)	✓	✓
Awk		✓
Boo			✓
CSS	✓		✓
Python Doctests			✓
Diff		✓	✓
Eiffel		✓
Elisp		✓
Fortran		✓ (1)	✓
Haskell		✓	✓
Genshi			✓
HTML	✓	✓	✓
IDL		✓
INI			✓
Javascript	✓	✓	✓
Lua			✓
m4		✓
Makefile		✓	✓
Mako			✓
Matlab (3)		✓	✓
Mygthy			✓
Objective-C		✓	✓
OCaml			✓
Pascal		✓	✓
Perl	✓	✓	✓
PHP	✓		✓
PSP	✓
Pyrex		✓
Python	✓	✓	✓
Ruby	✓	✓ (1)	✓
Scheme		✓	✓
Shell		✓	✓
Smarty			✓
SQL	✓	✓	✓
Troff		✓	✓
TCL		✓
Tex		✓	✓
Verilog	✓ (2)	✓
VHDL		✓
Visual Basic		✓	✓
VRML		✓
XML	✓		✓

(1) Not included in the Enscript distribution. Additional highlighting rules can be obtained for ​Ruby, ​C#, ​Fortran 90x/2003

(2) since Silvercity 0.9.7 released on 2006-11-23

(3) By default .m files are considered Objective-C files. In order to treat .m files as MATLAB files, add "text/matlab:m" to the "mime_map" setting in the [mimeviewer] section of trac.ini.

Extra Software

• GNU Enscript — ​http://www.gnu.org/software/enscript/
• GNU Enscript for Windows — ​http://gnuwin32.sourceforge.net/packages/enscript.htm
• SilverCity — ​http://silvercity.sf.net/
• Pygments — ​http://pygments.org/

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See also: WikiProcessors, WikiFormatting, TracWiki, TracBrowser