Fixes: U4-3481 Adding Scripting Files and Partial View Macro File with the same name and 'create macro' selected fails.

src/Umbraco.Web.UI/umbraco/create/DLRScripting.ascx

@@ -24,6 +24,9 @@
 
      <cc1:PropertyPanel runat="server">
         <asp:CheckBox ID="createMacro" Runat="server" Checked="true" Text="Create Macro"></asp:CheckBox>
+         <asp:CustomValidator ErrorMessage="<br/>A macro already exists with the specified name" ID="MacroExistsValidator" 
+            Display="Dynamic" ForeColor="red"
+            runat="server" OnServerValidate="MacroExistsValidator_OnServerValidate"/>
     </cc1:PropertyPanel>
 </cc1:Pane>
 

src/Umbraco.Web.UI/umbraco/create/PartialViewMacro.ascx

@@ -15,6 +15,9 @@
 
     <cc1:PropertyPanel runat="server">
         <asp:CheckBox ID="CreateMacroCheckBox" runat="server" Checked="true" Text="Create Macro"></asp:CheckBox>
+        <asp:CustomValidator ErrorMessage="<br/>A macro already exists with the specified name" ID="MacroExistsValidator" 
+            Display="Dynamic" ForeColor="red"
+            runat="server" OnServerValidate="MacroExistsValidator_OnServerValidate"/>
     </cc1:PropertyPanel>
 </cc1:Pane>
 

src/Umbraco.Web.UI/umbraco/create/PartialViewMacro.ascx.cs

@@ -45,7 +45,7 @@ namespace Umbraco.Web.UI.Umbraco.Create
             }
         }
 
-		protected void SubmitButton_Click(object sender, System.EventArgs e)
+		protected void SubmitButton_Click(object sender, EventArgs e)
 		{
 			if (Page.IsValid)
 			{			
@@ -66,5 +66,23 @@ namespace Umbraco.Web.UI.Umbraco.Create
 					.CloseModalWindow();				
 			}
 		}
+
+	    protected void MacroExistsValidator_OnServerValidate(object source, ServerValidateEventArgs args)
+	    {
+	        if (CreateMacroCheckBox.Checked)
+	        {
+                //TODO: Shouldn't this use our string functions to create the alias ?
+                var fileName = FileName.Text + ".cshtml";
+                var name = fileName
+                    .Substring(0, (fileName.LastIndexOf('.') + 1)).Trim('.')
+                    .SplitPascalCasing().ToFirstUpperInvariant();
+
+                var macro = ApplicationContext.Current.Services.MacroService.GetByAlias(name);
+                if (macro != null)
+                {
+                    args.IsValid = false;
+                }    
+	        }
+	    }
 	}
 }

src/Umbraco.Web.UI/umbraco/create/PartialViewMacro.ascx.designer.cs

@@ -48,6 +48,15 @@ namespace Umbraco.Web.UI.Umbraco.Create {
         /// </remarks>
         protected global::System.Web.UI.WebControls.CheckBox CreateMacroCheckBox;
         
+        /// <summary>
+        /// MacroExistsValidator control.
+        /// </summary>
+        /// <remarks>
+        /// Auto-generated field.
+        /// To modify move field declaration from designer file to code-behind file.
+        /// </remarks>
+        protected global::System.Web.UI.WebControls.CustomValidator MacroExistsValidator;
+        
         /// <summary>
         /// Textbox2 control.
         /// </summary>