ActiveSupport::SafeBuffer from .html_safe behaves weirdly

[gyfis]

Hi, I have a simple .haml file in rails:

- title = "<b>The dog</b> ate her cat's lunch"

.js-tooltip{title: title}
  Dog 1
.js-tooltip{title: title.html_safe}
  Dog 2

When observing the source code, the first <div> gets transformed and escaped properly and behaves as expected:

<div class='js-tooltip' title='&lt;b&gt;The dog&lt;/b&gt; ate her cat&#39;s lunch'>
  Dog 1
</div>

However, the second <div> gets transformed and escaped poorly, leading to an unfortunate accident that could have been avoided:

<div class='js-tooltip' title='<b>The dog</b> ate her cat's lunch'>
  Dog 2
</div>

It seems that haml-rails doesn't properly deal with ActiveSupport::SafeBuffer in element attributes (this bug doesn't occur when using = title).

Let me know if I can provide more info or examples!