diff --git a/platform/workspaceModel/storage/tests/testSrc/com/intellij/workspaceModel/storage/entities/TestEntities.kt b/platform/workspaceModel/storage/tests/testSrc/com/intellij/workspaceModel/storage/entities/TestEntities.kt
index a0842d4886bc..e03510ce211c 100644
--- a/platform/workspaceModel/storage/tests/testSrc/com/intellij/workspaceModel/storage/entities/TestEntities.kt
+++ b/platform/workspaceModel/storage/tests/testSrc/com/intellij/workspaceModel/storage/entities/TestEntities.kt
@@ -44,7 +44,6 @@ internal class ModifiableSampleEntity : ModifiableWorkspaceEntityBase<SampleEnti
   var stringProperty: String by EntityDataDelegation()
   var stringListProperty: List<String> by EntityDataDelegation()
   var fileProperty: VirtualFileUrl by EntityDataDelegation()
-
 }
 
 internal fun WorkspaceEntityStorageBuilder.addSampleEntity(stringProperty: String,
diff --git a/platform/workspaceModel/storage/tests/testSrc/com/intellij/workspaceModel/storage/propertyBased/EntityManipulations.kt b/platform/workspaceModel/storage/tests/testSrc/com/intellij/workspaceModel/storage/propertyBased/EntityManipulations.kt
index aa3fd210addb..71904510dfb1 100644
--- a/platform/workspaceModel/storage/tests/testSrc/com/intellij/workspaceModel/storage/propertyBased/EntityManipulations.kt
+++ b/platform/workspaceModel/storage/tests/testSrc/com/intellij/workspaceModel/storage/propertyBased/EntityManipulations.kt
@@ -12,7 +12,33 @@ import org.jetbrains.jetCheck.ImperativeCommand
 import org.junit.Assert
 
 internal fun getEntityManipulation(workspace: WorkspaceEntityStorageBuilderImpl): Generator<ImperativeCommand>? {
-  return Generator.anyOf(RemoveSomeEntity.create(workspace), EntityManipulation.addManipulations(workspace))
+  return Generator.anyOf(
+    RemoveSomeEntity.create(workspace),
+    EntityManipulation.addManipulations(workspace),
+    EntityManipulation.modifyManipulations(workspace)
+  )
+}
+
+internal interface EntityManipulation {
+  fun addManipulation(storage: WorkspaceEntityStorageBuilderImpl): AddEntity
+  fun modifyManipulation(storage: WorkspaceEntityStorageBuilderImpl): ModifyEntity<out WorkspaceEntity>
+
+  companion object {
+    fun addManipulations(storage: WorkspaceEntityStorageBuilderImpl): Generator<AddEntity> {
+      return Generator.sampledFrom(manipulations.map { it.addManipulation(storage) })
+    }
+
+    fun modifyManipulations(storage: WorkspaceEntityStorageBuilderImpl): Generator<ModifyEntity<*>> {
+      return Generator.sampledFrom(manipulations.map { it.modifyManipulation(storage) })
+    }
+
+    private val manipulations = listOf(
+      SampleEntityManipulation,
+      ParentEntityManipulation,
+      ChildEntityManipulation,
+      ChildWithOptionalParentManipulation
+    )
+  }
 }
 
 // Common for all entities
@@ -48,21 +74,21 @@ internal abstract class AddEntity(protected val storage: WorkspaceEntityStorageB
   }
 }
 
-internal interface EntityManipulation {
-  fun addManipulation(storage: WorkspaceEntityStorageBuilderImpl): AddEntity
-  //fun modify(storage: WorkspaceEntityStorageBuilderImpl)
+internal abstract class ModifyEntity<E : WorkspaceEntity>(protected val storage: WorkspaceEntityStorageBuilderImpl,
+                                                          private val entityDescription: String,
+                                                          private val classId: Int) : ImperativeCommand {
+  abstract fun modifyEntity(entity: E, someProperty: String, env: ImperativeCommand.Environment): Boolean
 
-  companion object {
-    fun addManipulations(storage: WorkspaceEntityStorageBuilderImpl): Generator<AddEntity> {
-      return Generator.sampledFrom(manipulations.map { it.addManipulation(storage) })
-    }
+  final override fun performCommand(env: ImperativeCommand.Environment) {
+    env.logMessage("Trying to modify $entityDescription entity")
+    val property = env.generateValue(randomNames, null)
 
-    private val manipulations = listOf(
-      SampleEntityManipulation,
-      ParentEntityManipulation,
-      ChildEntityManipulation,
-      ChildWithOptionalParentManipulation
-    )
+    val entityId = env.generateValue(EntityIdOfFamilyGenerator.create(storage, classId), null)
+    if (entityId == null) return
+
+    val entity = storage.entityDataByIdOrDie(entityId).createEntity(storage) as E
+    modifyEntity(entity, property, env)
+    env.logMessage("----------------------------------")
   }
 }
 
@@ -77,6 +103,21 @@ private object ChildWithOptionalParentManipulation : EntityManipulation {
       }
     }
   }
+
+  override fun modifyManipulation(storage: WorkspaceEntityStorageBuilderImpl): ModifyEntity<ChildWithOptionalParentEntity> {
+    return object : ModifyEntity<ChildWithOptionalParentEntity>(storage, "ChildWithOptionalParent",
+                                                                ChildWithOptionalParentEntity::class.java.toClassId()) {
+      override fun modifyEntity(entity: ChildWithOptionalParentEntity, someProperty: String, env: ImperativeCommand.Environment): Boolean {
+        val selectedModification = env.generateValue(Generator.integers(0, 0), null)
+        val modification: ModifiableChildWithOptionalParentEntity.() -> Unit = when (selectedModification) {
+          0 -> { -> childProperty = env.generateValue(randomNames, "Change childProperty to %s") }
+          else -> error("Undefined modification")
+        }
+        storage.modifyEntity(ModifiableChildWithOptionalParentEntity::class.java, entity, modification)
+        return true
+      }
+    }
+  }
 }
 
 private object ChildEntityManipulation : EntityManipulation {
@@ -90,6 +131,20 @@ private object ChildEntityManipulation : EntityManipulation {
       }
     }
   }
+
+  override fun modifyManipulation(storage: WorkspaceEntityStorageBuilderImpl): ModifyEntity<ChildEntity> {
+    return object : ModifyEntity<ChildEntity>(storage, "Child", ChildEntity::class.java.toClassId()) {
+      override fun modifyEntity(entity: ChildEntity, someProperty: String, env: ImperativeCommand.Environment): Boolean {
+        val selectedModification = env.generateValue(Generator.integers(0, 0), null)
+        val modification: ModifiableChildEntity.() -> Unit = when (selectedModification) {
+          0 -> { -> childProperty = env.generateValue(randomNames, "Change childProperty to %s") }
+          else -> error("Undefined modification")
+        }
+        storage.modifyEntity(ModifiableChildEntity::class.java, entity, modification)
+        return true
+      }
+    }
+  }
 }
 
 private object ParentEntityManipulation : EntityManipulation {
@@ -100,6 +155,20 @@ private object ParentEntityManipulation : EntityManipulation {
       }
     }
   }
+
+  override fun modifyManipulation(storage: WorkspaceEntityStorageBuilderImpl): ModifyEntity<ParentEntity> {
+    return object : ModifyEntity<ParentEntity>(storage, "Parent", ParentEntity::class.java.toClassId()) {
+      override fun modifyEntity(entity: ParentEntity, someProperty: String, env: ImperativeCommand.Environment): Boolean {
+        val selectedModification = env.generateValue(Generator.integers(0, 0), null)
+        val modification: ModifiableParentEntity.() -> Unit = when (selectedModification) {
+          0 -> { -> parentProperty = env.generateValue(randomNames, "Change parentProperty to %s") }
+          else -> error("Undefined modification")
+        }
+        storage.modifyEntity(ModifiableParentEntity::class.java, entity, modification)
+        return true
+      }
+    }
+  }
 }
 
 private object SampleEntityManipulation : EntityManipulation {
@@ -110,5 +179,20 @@ private object SampleEntityManipulation : EntityManipulation {
       }
     }
   }
+
+  override fun modifyManipulation(storage: WorkspaceEntityStorageBuilderImpl): ModifyEntity<SampleEntity> {
+    return object : ModifyEntity<SampleEntity>(storage, "Sample", SampleEntity::class.java.toClassId()) {
+      override fun modifyEntity(entity: SampleEntity, someProperty: String, env: ImperativeCommand.Environment): Boolean {
+        val selectedModification = env.generateValue(Generator.integers(0, 1), null)
+        val modification: ModifiableSampleEntity.() -> Unit = when (selectedModification) {
+          0 -> { -> booleanProperty = env.generateValue(Generator.booleans(), "Change booleanProperty to %s") }
+          1 -> { -> stringProperty = env.generateValue(randomNames, "Change stringProperty to %s") }
+          else -> error("Undefined modification")
+        }
+        storage.modifyEntity(ModifiableSampleEntity::class.java, entity, modification)
+        return true
+      }
+    }
+  }
 }