On-the-fly syntax highlighting when using Markdown

Review Board 2.0 introduced Markdown support for text fields, and we’ve been iterating on this since. One nice advantage to using Markdown is that it’s really easy to syntax-highlight a code fragment, like:

def foo():
print "oh hi there"

When saving the comment, this would appear rendered with some syntax highlighting, same as the diff viewer.

In 2.5, we’re adding on-the-fly syntax highlighting for most popular languages: CoffeeScript, CSS, Go, HTML, JavaScript, Perl, PHP, Python, ReStructuredText, Ruby, Shell Scripts, SQL, XML, and YAML.

That means when you type code in a code block, like above, it will show the syntax highlighting immediately, without having to save.

Now, it’s not perfect. We use a different highlighting engine for rendered content vs. on-the-fly content, and they don’t 100% agree on how things should be styled, but it’s close enough.

We’re gaining this ability through an upgrade of CodeMirror, the widget we use for the text fields. We’re giving 5.5 a try (we previously tried upgrading to 4.2 and had issues, but so far so good with 5.5).

This will all ship with Review Board 2.5 RC 1.

Christian Hammond

President/CEO of Beanbag. Developer of Review Board and RBCommons. Lover of sushi and bees. Not at the same time.

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