Add Missing Tests for delete Account Functionality

Author: Agaba-derrick

hiero-enterprise-base/src/test/java/com/openelements/hiero/base/test/AccountClientImplTest.java

@@ -5,10 +5,7 @@
 import com.openelements.hiero.base.data.Account;
 import com.hedera.hashgraph.sdk.Hbar;
 import com.openelements.hiero.base.HieroException;
-import com.openelements.hiero.base.protocol.data.AccountBalanceRequest;
-import com.openelements.hiero.base.protocol.data.AccountBalanceResponse;
-import com.openelements.hiero.base.protocol.data.AccountCreateRequest;
-import com.openelements.hiero.base.protocol.data.AccountCreateResult;
+import com.openelements.hiero.base.protocol.data.*;
 import com.openelements.hiero.base.protocol.ProtocolLayerClient;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
@@ -145,4 +142,47 @@ void testCreateAccount_hieroExceptionThrown() throws HieroException {
         Exception exception = assertThrows(HieroException.class, () -> accountClientImpl.createAccount(initialBalance));
         assertEquals("Transaction failed", exception.getMessage());
     }
+
+
+    @Test
+    void DeleteAccount_throwsHieroException() throws HieroException {
+        Account mockAccount = mock(Account.class);
+
+        doThrow(new HieroException("Deletion failed")).when(mockProtocolLayerClient)
+                .executeAccountDeleteTransaction(any(AccountDeleteRequest.class));
+
+        HieroException exception = assertThrows(HieroException.class,
+                () -> accountClientImpl.deleteAccount(mockAccount));
+        assertEquals("Deletion failed", exception.getMessage());
+    }
+
+    @Test
+    void DeleteAccount_withSameFromAndToAccount_throwsIllegalArgumentException() {
+        // Arrange
+        Account account = mock(Account.class);
+
+        // Act & Assert
+        IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () ->
+                accountClientImpl.deleteAccount(account, account)
+        );
+
+        assertEquals("transferFoundsToAccount must be different from toDelete", exception.getMessage());
+    }
+
+    @Test
+    void DeleteAccount_nullAccount_throwsNullPointerException() {
+        assertThrows(NullPointerException.class, () -> accountClientImpl.deleteAccount(null));
+    }
+
+    @Test
+    void DeleteAccount_withTransfer_nullAccount_throwsNullPointerException() {
+        Account toAccount = mock(Account.class);
+        assertThrows(NullPointerException.class, () -> accountClientImpl.deleteAccount(null, toAccount));
+    }
+
+    @Test
+    void DeleteAccount_withSameAccount_throwsIllegalArgumentException() {
+        Account account = mock(Account.class);
+        assertThrows(IllegalArgumentException.class, () -> accountClientImpl.deleteAccount(account, account));
+    }
 }