EncryptedKVStorage: can destroy exisint creating one with a new key

src/commonTest/kotlin/StorageTest.kt

@@ -1,11 +1,13 @@
 import kotlinx.coroutines.test.runTest
 import net.sergeych.bintools.*
 import net.sergeych.bipack.decodeFromBipack
+import net.sergeych.crypto2.DecryptionFailedException
 import net.sergeych.crypto2.EncryptedKVStorage
 import net.sergeych.crypto2.SymmetricKey
 import net.sergeych.crypto2.initCrypto
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertFailsWith
 import kotlin.test.assertNull
 
 class StorageTest {
@@ -15,7 +17,7 @@ class StorageTest {
         initCrypto()
         val plain = MemoryKVStorage()
         val key = SymmetricKey.new()
-        val storage = EncryptedKVStorage(plain, key)
+        val storage = EncryptedKVStorage(plain, key, removeExisting = false)
 
         var hello by storage.optStored<String>()
         assertNull(hello)
@@ -42,8 +44,9 @@ class StorageTest {
             assertEquals("bar", bar)
             assertEquals("bazz", bazz)
         }
+
         fun setup(s: KVStorage, k: SymmetricKey): EncryptedKVStorage {
-            val x = EncryptedKVStorage(s, k)
+            val x = EncryptedKVStorage(s, k, removeExisting = false)
             var foo by x.stored("1")
             var bar by x.stored("2")
             var bazz by x.stored("3")
@@ -52,6 +55,7 @@ class StorageTest {
             bazz = "bazz"
             return x
         }
+
         val k1 = SymmetricKey.new()
         val k2 = SymmetricKey.new()
         val plain = MemoryKVStorage()
@@ -62,6 +66,18 @@ class StorageTest {
 //        val s2  = EncryptedKVStorage(plain, k2)
 //        test(s2)
     }
+
+    @Test
+    fun testDeleteExisting() = runTest {
+        initCrypto()
+        val plain = MemoryKVStorage()
+        val c1 = EncryptedKVStorage(plain, SymmetricKey.new(), removeExisting = false)  // 1
+        c1.write("hello", "world")
+        assertFailsWith<DecryptionFailedException> {
+            val c2 = EncryptedKVStorage(plain, SymmetricKey.new(), removeExisting = false)  // 2
+        }
+        val c2 = EncryptedKVStorage(plain, SymmetricKey.new(), removeExisting = true)  // 2
+    }
 }
 
 fun KVStorage.dump() {