hoplon.goog do! sets attributes to "null" instead of removing them when val is nil

[thedavidmeister]

Just noticed this when running my test suite requiring hoplon.goog instead of hoplon.jquery.

Expected:

(div :data-foo (cell= (when foo "foo")))
(reset! foo true)
; <div data-foo="foo"></div>
(reset! foo false)
; <div></div>

Actual:

(div :data-foo (cell= (when foo "foo")))
(reset! foo true)
; <div data-foo="foo"></div>
(reset! foo false)
; <div data-foo="null"></div>

This at least breaks [data-foo] style CSS selectors that only look for the existence of the attribute.

[burn2delete]

@thedavidmeister thanks for reporting this, i'll get a patch in.

[burn2delete]

looking at the code for this one, appears that both are plagued with the same problem, values are always passing the (= false v) check, the difference is that jquery is correctly handling the nil case.

The fix is to change (if (= false v) ... -> (if-not v ... patch to follow.