Replace underscores in HTML5 data attribute names with hyphens

[codyrobbins]

This is a feature request rather than a bug.

The example

%a{:href=>"/posts", :data => {:author_id => 123}} Posts By Author

given in the reference produces

<a data-author_id='123' href='/posts'>Posts By Author</a>

This markup is hideously ugly with the underscore—the data attribute should be named data-author-id. Since HAML isn’t substituting hyphens for the underscores automatically, there doesn’t really seem to be any advantage to using the special :data attribute key over just doing

%a{:href=>"/posts", 'data-author-id' => 123} Posts By Author

Using the :data key is more typing and you still end up having a string hash key for the attribute anyways:

%a{:href=>"/posts", :data => {'author-id' => 123}} Posts By Author

What’s the point?