Linter suggestion - Avoid Unescape HTML

[gravitystorm]

Haml contains a method to ensure that generated html is not escaped. Specifically, you can use != instead of = if you want to avoid escaping.

https://haml.info/docs/yardoc/file.REFERENCE.html#unescaping_html

= "I feel <strong>!"
!= "I feel <strong>!"

However, like using raw and h() and .html_safe and friends, it's very easy to accidentally create security holes in your application

!= "Username: <strong>#{user.name}</strong>"

In most cases != is undesirable, and can be avoided by using safer methods (e.g. in Rails, by using SafeBuffers when building in views or helpers).

I'd therefore like to see a linter that can flag up uses of !=, in case they slip through code review.