add tests

Signed-off-by: Karim Taam <karim.t2am@gmail.com>

Author: matkt

constantine/src/test/java/org/hyperledger/besu/nativelib/constantine/LibConstantineKeccak256Test.java

@@ -0,0 +1,22 @@
+package org.hyperledger.besu.nativelib.constantine;
+
+import org.apache.tuweni.bytes.Bytes;
+import org.junit.Test;
+
+import java.nio.charset.StandardCharsets;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThrows;
+
+public class LibConstantineKeccak256Test {
+
+    @Test
+    public void testKeccakNonimalCase() {
+        final byte[] inputs = "testKeccak256".getBytes(StandardCharsets.UTF_8);
+        final byte[] result = LibConstantineKeccak256.keccak256(inputs);
+        assertEquals(Bytes.wrap(result), Bytes.fromHexString("0xfe8baa653979909c621153b53c973bab3832768b5e77896a5b5944d20d48c7a6"));
+    }
+
+
+}