Syntax Coloring of Source Code

Trac supports language-specific syntax highlighting of source code within wiki formatted text in [WikiProcessors#CodeHighlightingSupport 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.

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 [TracIni#mimeviewer-section 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 [TracIni#pygments-lexer-section environment configuration].

Syntax Coloring Support

Supported languages

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 java.

Direct Rendering

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 text/xml mimetype.

HTML documents are directly rendered only if the render_unsafe_html settings are enabled in your TracIni file. See [TracIni#attachment-render_unsafe_content-option "[attachment] render_unsafe_content"], [TracIni#browser-render_unsafe_content-option "[browser] render_unsafe_content"] and [TracIni#wiki-render_unsafe_content-option "[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

[[KnownMimeTypes]]