Index: Application/Ringtoets/test/Application.Ringtoets.Storage.Test/Create/GrassCoverErosionInwards/DikeProfileCreateExtensionsTest.cs
===================================================================
diff -u -rb954fb6f2dd56ffb96be7b61ab129f19d879d2ab -rbc7cd9cbf90d04580e6b3542c56edc590867c43a
--- Application/Ringtoets/test/Application.Ringtoets.Storage.Test/Create/GrassCoverErosionInwards/DikeProfileCreateExtensionsTest.cs	(.../DikeProfileCreateExtensionsTest.cs)	(revision b954fb6f2dd56ffb96be7b61ab129f19d879d2ab)
+++ Application/Ringtoets/test/Application.Ringtoets.Storage.Test/Create/GrassCoverErosionInwards/DikeProfileCreateExtensionsTest.cs	(.../DikeProfileCreateExtensionsTest.cs)	(revision bc7cd9cbf90d04580e6b3542c56edc590867c43a)
@@ -179,5 +179,33 @@
             registry.TransferIds();
             Assert.AreEqual(entity.DikeProfileEntityId, dikeProfile.StorageId);
         }
+
+        [Test]
+        public void Create_DikeProfileAlreadyRegistered_ReturnRegisteredEntity()
+        {
+            // Setup
+            var dikeProfile = new DikeProfile(new Point2D(1.1, 2.2),
+                                              new[]
+                                              {
+                                                  new RoughnessPoint(new Point2D(3.3, 4.4), 0.75),
+                                                  new RoughnessPoint(new Point2D(5.5, 6.6), 0.75)
+                                              },
+                                              new[]
+                                              {
+                                                  new Point2D(7.7, 8.8),
+                                                  new Point2D(9.9, 10.10)
+                                              }, null, new DikeProfile.ConstructionProperties());
+            var registry = new PersistenceRegistry();
+            DikeProfileEntity entity1 = dikeProfile.Create(registry);
+
+            // Precondition:
+            Assert.IsTrue(registry.Contains(dikeProfile));
+
+            // Call
+            DikeProfileEntity entity2 = dikeProfile.Create(registry);
+
+            // Assert
+            Assert.AreSame(entity1, entity2);
+        }
     }
 }
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