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. Syntax coloring is provided using Pygments, which covers a wide range of programming languages and other structured texts, and is actively supported. If Pygments is not available, Trac will display the content as plain text.
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.
Pygments lexer options can be specified as WikiProcessor arguments and defaults can be set in the environment configuration.
Syntax Coloring Support
The list of currently supported languages can be found on the supported languages page. The list represents the languages supported in the most recent version of Pygments, so the languages actually supported in your installation could differ if you have an older version installed. The listing of supported lexers provides additional information about the default mime type to keyword mappings.
Explicit control of the mime type associated with a WikiProcessor and file extension is available through the
mime_map setting. For example, by default
.m files are considered Objective-C files. In order to treat
.m files as MATLAB files, add
text/matlab:m to the [mimeviewer] mime_map option.
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
Rich content may be directly rendered instead of syntax highlighted. This usually depends on which auxiliary packages are installed and 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. It will be syntax highlighted otherwise.
Similarly, 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. If you want to ensure that an HTML document gets syntax highlighted and not rendered, use the
HTML documents are directly rendered only if the
render_unsafe_html settings are enabled in your TracIni file. See [attachment] render_unsafe_content, [browser] render_unsafe_content and [wiki] render_unsafe_content. The setting is present in multiple sections because there are different security concerns depending on where the document comes from.
Known MIME types
See also: WikiProcessors, WikiFormatting, TracWiki, TracBrowser