fix($compile): link async+replace element transclusion directives with comment element

Previously, element transclusion directives would not receive a comment node in their
link functions when they were the root of an asynchronous replace template. This would
cause duplicate elements to appear in an ng-if expression within ng-repeat.

Closes angular#6006

Author: caitp

src/ng/compile.js

@@ -1142,7 +1142,7 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
           templateDirective = previousCompileContext.templateDirective,
           nonTlbTranscludeDirective = previousCompileContext.nonTlbTranscludeDirective,
           hasTranscludeDirective = false,
-          hasElementTranscludeDirective = false,
+          hasElementTranscludeDirective = previousCompileContext.hasElementTranscludeDirective,
           $compileNode = templateAttrs.$$element = jqLite(compileNode),
           directive,
           directiveName,
@@ -1316,6 +1316,7 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
 
       nodeLinkFn.scope = newScopeDirective && newScopeDirective.scope === true;
       nodeLinkFn.transclude = hasTranscludeDirective && childTranscludeFn;
+      previousCompileContext.hasElementTranscludeDirective = hasElementTranscludeDirective;
 
       // might be normal or delayed nodeLinkFn depending on if templateUrl is present
       return nodeLinkFn;
@@ -1712,8 +1713,13 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
 
             if (beforeTemplateLinkNode !== beforeTemplateCompileNode) {
               var oldClasses = beforeTemplateLinkNode.className;
-              // it was cloned therefore we have to clone as well.
-              linkNode = jqLiteClone(compileNode);
+
+              if (!(previousCompileContext.hasElementTranscludeDirective &&
+                  origAsyncDirective.replace)) {
+                // it was cloned therefore we have to clone as well.
+                linkNode = jqLiteClone(compileNode);
+              }
+
               replaceWith(linkRootElement, jqLite(beforeTemplateLinkNode), linkNode);
 
               // Copy in CSS classes from original node

test/ng/compileSpec.js

@@ -3972,6 +3972,57 @@ describe('$compile', function() {
         });
       });
 
+      // issue #6006
+      it('should link directive with $element as a comment node', function() {
+        module(function($provide) {
+          directive('innerAgain', function(log) {
+            return {
+              transclude: 'element',
+              link: function(scope, element, attr, controllers, transclude) {
+                log('innerAgain:'+lowercase(nodeName_(element))+':'+trim(element[0].data));
+                transclude(scope, function(clone) {
+                  element.parent().append(clone);
+                });
+              }
+            };
+          });
+          directive('inner', function(log) {
+            return {
+              replace: true,
+              templateUrl: 'inner.html',
+              link: function(scope, element) {
+                log('inner:'+lowercase(nodeName_(element))+':'+trim(element[0].data));
+              }
+            };
+          });
+          directive('outer', function(log) {
+            return {
+              transclude: 'element',
+              link: function(scope, element, attrs, controllers, transclude) {
+                log('outer:'+lowercase(nodeName_(element))+':'+trim(element[0].data));
+                transclude(scope, function(clone) {
+                  element.parent().append(clone);
+                });
+              }
+            };
+          });
+        });
+        inject(function(log, $compile, $rootScope, $templateCache) {
+          $templateCache.put('inner.html', '<div inner-again><p>Content</p></div>');
+          element = $compile('<div><div outer><div inner></div></div></div>')($rootScope);
+          $rootScope.$digest();
+          var child = element.children();
+
+          expect(log.toArray()).toEqual([
+            "outer:#comment:outer:",
+            "innerAgain:#comment:innerAgain:",
+            "inner:#comment:innerAgain:"]);
+          expect(child.length).toBe(1);
+          expect(child.contents().length).toBe(2);
+          expect(lowercase(nodeName_(child.contents().eq(0)))).toBe('#comment');
+          expect(lowercase(nodeName_(child.contents().eq(1)))).toBe('div');
+        });
+      });
     });
 
     it('should safely create transclude comment node and not break with "-->"',