Provide escape at top of Save() if !isDirty

By moving all of the key variables and logic for `isDirty` to the top of `Save()` (baaaf4d
), we can now escape the `Save()` method early if nothing has actually changed. This prevents the need to populate the indexed attributes `DataTable`, extended attributes XML, and command parameters, even though none of those would be used.

(Alternatively, it saves from wrapping the bulk of the method in a conditional block, which I wanted to avoid.)

To facilitate this, the closing logic of iterating over child topics as part of the `isRecursive` support is centralized into a new local `recurse()` method, so that we don't need to repeat that logic.

Author: JeremyCaney

OnTopic.Data.Sql/SqlTopicRepository.cs

@@ -362,6 +362,14 @@ List<Topic> unresolvedRelationships
         indexedAttributeList.Any() ||
         extendedAttributeList.Any(a => a.IsExtendedAttribute == false);
 
+      /*------------------------------------------------------------------------------------------------------------------------
+      | Bypass is not dirty
+      \-----------------------------------------------------------------------------------------------------------------------*/
+      if (!isDirty) {
+        recurse();
+        return topic.Id;
+      }
+
       /*------------------------------------------------------------------------------------------------------------------------
       | Establish attribute containers with schema
       \-----------------------------------------------------------------------------------------------------------------------*/
@@ -472,10 +480,9 @@ void addUnmatchedAttribute(string key) {
       \-----------------------------------------------------------------------------------------------------------------------*/
       try {
 
-        if (isDirty) {
-          command.ExecuteNonQuery();
-          topic.Id              = command.GetReturnCode();
-        }
+        command.ExecuteNonQuery();
+
+        topic.Id                = command.GetReturnCode();
 
         Contract.Assume<InvalidOperationException>(
           topic.Id > 0,
@@ -510,19 +517,22 @@ void addUnmatchedAttribute(string key) {
       }
 
       /*------------------------------------------------------------------------------------------------------------------------
-      | Recurse
+      | Return value
       \-----------------------------------------------------------------------------------------------------------------------*/
-      if (isRecursive) {
-        foreach (var childTopic in topic.Children) {
-          childTopic.Attributes.SetValue("ParentID", topic.Id.ToString(CultureInfo.InvariantCulture));
-          Save(childTopic, isRecursive, isDraft, connection, unresolvedRelationships);
-        }
-      }
+      recurse();
+      return topic.Id;
 
       /*------------------------------------------------------------------------------------------------------------------------
-      | Return value
+      | Recurse
       \-----------------------------------------------------------------------------------------------------------------------*/
-      return topic.Id;
+      void recurse() {
+        if (isRecursive) {
+          foreach (var childTopic in topic.Children) {
+            childTopic.Attributes.SetValue("ParentID", topic.Id.ToString(CultureInfo.InvariantCulture));
+            Save(childTopic, isRecursive, isDraft, connection, unresolvedRelationships);
+          }
+        }
+      }
 
     }