Use transclusion for status-button directive

Using transclusion allows for the directive to be set on an element
with non-trivial content and have that content nested inside the
status-button wrapper spans, but pre-bound to its lexical markup
scope.

Not sure we'll need it here, but I also wanted to see how one might
approximate 'replace' now that it's deprecated. The answer is by
not replacing but just adding the template you want after the passed
placeholder comment node.

h/static/scripts/directives/status-button.coffee

@@ -13,7 +13,7 @@ statusButton = ->
   STATE_SUCCESS = 'success'
 
   template = '''
-  <span class="btn-with-message" status-button-state>
+  <span class="btn-with-message">
     <span class="btn-message btn-message-loading">
       <span class="btn-icon spinner"><span><span></span></span></span>
     </span>
@@ -23,25 +23,22 @@ statusButton = ->
   </span>
   '''
 
-  compile: (button, attr) ->
+  link: (scope, placeholder, attr, ctrl, transclude) ->
     targetForm = attr.statusButton
 
     unless targetForm
       throw new Error('status-button attribute should provide a form name')
 
-    # Remove the attribute to prevent recusive parsing.
-    button.removeAttr('status-button')
+    elem = angular.element(template)
+    placeholder.after(elem)
+    transclude(scope, (clone) -> elem.append(clone))
 
-    wrapper = angular.element(template)
-    wrapper.insertBefore(button)
-    wrapper.append(button)
-
-    post: (scope, elem, attr) ->
     scope.$on 'formState', (event, formName, formState) ->
       return unless formName == targetForm
       unless formState in [STATE_LOADING, STATE_SUCCESS]
         formState = ''
-        wrapper.attr(STATE_ATTRIBUTE, formState)
+      elem.attr(STATE_ATTRIBUTE, formState)
+  transclude: 'element'
 
 
 angular.module('h.directives').directive('statusButton', statusButton)

tests/js/directives/status-button-test.coffee

@@ -16,26 +16,21 @@ describe 'h.directives.statusButton', ->
     <button status-button="test">Test Button</button>
     '''
 
-    $element = $compile(angular.element(template))($scope)
+    $element = $compile(angular.element(template))($scope).next()
 
   it 'wraps the button with status labels', ->
-    parent = $element.parent()
-    assert.include(parent.prop('className'), 'btn-with-message')
-
-    assert.equal(parent.find('.btn-message-loading').length, 1)
-    assert.equal(parent.find('.btn-message-success').length, 1)
+    assert.include($element.prop('className'), 'btn-with-message')
+    assert.equal($element.find('.btn-message-loading').length, 1)
+    assert.equal($element.find('.btn-message-success').length, 1)
 
   it 'sets the status-button-state attribute when a loading event is triggered', ->
-    parent = $element.parent()
     $scope.$emit('formState', 'test', 'loading')
-    assert.equal(parent.attr('status-button-state'), 'loading')
+    assert.equal($element.attr('status-button-state'), 'loading')
 
   it 'sets the status-button-state attribute when a success event is triggered', ->
-    parent = $element.parent()
     $scope.$emit('formState', 'test', 'success')
-    assert.equal(parent.attr('status-button-state'), 'success')
+    assert.equal($element.attr('status-button-state'), 'success')
 
   it 'unsets the status-button-state attribute when another event is triggered', ->
-    parent = $element.parent()
     $scope.$emit('formState', 'test', 'reset')
-    assert.equal(parent.attr('status-button-state'), '')
+    assert.equal($element.attr('status-button-state'), '')