Undo works.

Author: Hosch250

Rubberduck.SourceControl/SourceControlProviderBase.cs

@@ -103,9 +103,7 @@ public virtual void Undo(string filePath)
         {
             var componentName = Path.GetFileNameWithoutExtension(filePath);
 
-           //GetFileNameWithoutExtension returns empty string if it's not a file
-           //https://msdn.microsoft.com/en-us/library/system.io.path.getfilenamewithoutextension%28v=vs.110%29.aspx
-            if (componentName != string.Empty)
+            if (!File.Exists(filePath))
             {
                 var component = Project.VBComponents.Item(componentName);
                 Project.VBComponents.RemoveSafely(component);

Rubberduck.VBEEditor/Extensions/VBComponentsExtensions.cs

@@ -1,4 +1,5 @@
-using System.IO;
+using System;
+using System.IO;
 using Microsoft.Vbe.Interop;
 
 // todo: untangle this mess
@@ -37,6 +38,8 @@ public static void ImportSourceFile(this VBComponents components, string filePat
             var ext = Path.GetExtension(filePath);
             var fileName = Path.GetFileNameWithoutExtension(filePath);
 
+            if (!File.Exists(filePath)) { return; }
+
             if (ext == VBComponentExtensions.DocClassExtension)
             {
                 var component = components.Item(fileName);