All the logic is based on the HTML_ESCAPE constant available in
ERB::Util, so it seems more logic to have the entire method there and
just delegate the helper to use it.
* Additionally, instead of doing concat("</form>".html_safe), you can do
safe_concat("</form>"), which will skip both the flag set, and the flag
check.
* For the first pass, I converted virtually all #html_safe!s to #html_safe,
and the tests pass. A further optimization would be to try to use
#safe_concat as much as possible, reducing the performance impact if
we know up front that a String is safe.
This consists of:
* String#html_safe! a method to mark a string as 'safe'
* ActionView::SafeBuffer a string subclass which escapes anything unsafe which is concatenated to it
* Calls to String#html_safe! throughout the rails helpers
* a 'raw' helper which lets you concatenate trusted HTML from non-safety-aware sources (e.g. presantized strings in the DB)
* New ERB implementation based on erubis which uses a SafeBuffer instead of a String
Hat tip to Django for the inspiration.