Update ChaCha20Test.java

Author: Keykyrios

src/test/java/com/thealgorithms/ciphers/ChaCha20Test.java

@@ -6,30 +6,36 @@
 
 public class ChaCha20Test {
 
-    // RFC 8439 Section 2.4.2 Test Vector (114 bytes total, counter starts at 1)
+    // RFC 8439 Section 2.4.2 test vector (114 bytes, counter starts at 1)
     private static final byte[] RFC8439_KEY =
-            hexStringToByteArray("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f");
+        hexStringToByteArray("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f");
     private static final byte[] RFC8439_NONCE =
-            hexStringToByteArray("000000000000004a00000000");
+        hexStringToByteArray("000000000000004a00000000");
 
+    // 114-byte plaintext from RFC 8439
     private static final byte[] RFC8439_PLAINTEXT_114 = hexStringToByteArray(
-            "4c616469657320616e642047656e746c656d656e206f662074686520636c617373206f66202739393a204966204920636f756c64206f6666657220796f75206f6e6c79206f6e652074697020666f7220746865206675747572652c2073756e73637265656e20776f756c642062652069742e");
+        "4c616469657320616e642047656e746c656d656e206f662074686520636c617373206f66202739393a20"
+      + "4966204920636f756c64206f6666657220796f75206f6e6c79206f6e652074697020666f722074686520"
+      + "6675747572652c2073756e73637265656e20776f756c642062652069742e");
 
+    // 114-byte ciphertext from RFC 8439
     private static final byte[] RFC8439_CIPHERTEXT_114 = hexStringToByteArray(
-            "6e2e359a2568f98041ba0728dd0d6981e97e7aec1d4360c20a27afccfd9fae0bf91b65c5524733ab8f58375fcd4af034bd16adec164f7a2bda3dc0343a99a46c6e6593372ed8b9970cdbd7d8f5d9d3e0e6c90b8ed397b6c96b6f2ed8c8f0a5c9e6a2e6b1d58d88c7f1e9c7b3cda85a1b");
+        "6e2e359a2568f98041ba0728dd0d6981e97e7aec1d4360c20a27afccfd9fae0bf91b65c5524733ab8f58"
+      + "375fcd4af034bd16adec164f7a2bda3dc0343a99a46c6e6593372ed8b9970cdbd7d8f5d9d3e0e6c90b8e"
+      + "d397b6c96b6f2ed8c8f0a5c9e6a2e6b1d58d88c7f1e9c7b3cda85a1b");
 
     @Test
     public void testEncryptRFC8439Vector114Bytes() {
         byte[] ciphertext = ChaCha20.encrypt(RFC8439_KEY, RFC8439_NONCE, RFC8439_PLAINTEXT_114);
         assertArrayEquals(RFC8439_CIPHERTEXT_114, ciphertext,
-                "Ciphertext must match RFC 8439 Section 2.4.2 test vector");
+            "Ciphertext must match RFC 8439 Section 2.4.2 test vector");
     }
 
     @Test
     public void testDecryptRFC8439Vector114Bytes() {
         byte[] plaintext = ChaCha20.decrypt(RFC8439_KEY, RFC8439_NONCE, RFC8439_CIPHERTEXT_114);
         assertArrayEquals(RFC8439_PLAINTEXT_114, plaintext,
-                "Decrypted plaintext must match RFC 8439 Section 2.4.2 test vector");
+            "Decrypted plaintext must match RFC 8439 Section 2.4.2 test vector");
     }
 
     @Test
@@ -55,38 +61,49 @@ public void testEmptyPlaintext() {
     public void testInvalidKeySize() {
         byte[] nonce = new byte[12];
         byte[] data = {1, 2, 3};
-        assertThrows(IllegalArgumentException.class, () -> ChaCha20.encrypt(new byte[31], nonce, data));
-        assertThrows(IllegalArgumentException.class, () -> ChaCha20.encrypt(new byte[33], nonce, data));
+        assertThrows(IllegalArgumentException.class,
+            () -> ChaCha20.encrypt(new byte[31], nonce, data));
+        assertThrows(IllegalArgumentException.class,
+            () -> ChaCha20.encrypt(new byte[33], nonce, data));
     }
 
     @Test
     public void testInvalidNonceSize() {
         byte[] key = new byte[32];
         byte[] data = {1, 2, 3};
-        assertThrows(IllegalArgumentException.class, () -> ChaCha20.encrypt(key, new byte[11], data));
-        assertThrows(IllegalArgumentException.class, () -> ChaCha20.encrypt(key, new byte[13], data));
+        assertThrows(IllegalArgumentException.class,
+            () -> ChaCha20.encrypt(key, new byte[11], data));
+        assertThrows(IllegalArgumentException.class,
+            () -> ChaCha20.encrypt(key, new byte[13], data));
     }
 
     @Test
     public void testNullInputs() {
         byte[] key = new byte[32];
         byte[] nonce = new byte[12];
         byte[] data = {1, 2, 3};
-        assertThrows(IllegalArgumentException.class, () -> ChaCha20.encrypt(null, nonce, data));
-        assertThrows(IllegalArgumentException.class, () -> ChaCha20.encrypt(key, null, data));
-        assertThrows(IllegalArgumentException.class, () -> ChaCha20.encrypt(key, nonce, null));
-        assertThrows(IllegalArgumentException.class, () -> ChaCha20.decrypt(null, nonce, data));
-        assertThrows(IllegalArgumentException.class, () -> ChaCha20.decrypt(key, null, data));
-        assertThrows(IllegalArgumentException.class, () -> ChaCha20.decrypt(key, nonce, null));
+        assertThrows(IllegalArgumentException.class,
+            () -> ChaCha20.encrypt(null, nonce, data));
+        assertThrows(IllegalArgumentException.class,
+            () -> ChaCha20.encrypt(key, null, data));
+        assertThrows(IllegalArgumentException.class,
+            () -> ChaCha20.encrypt(key, nonce, null));
+        assertThrows(IllegalArgumentException.class,
+            () -> ChaCha20.decrypt(null, nonce, data));
+        assertThrows(IllegalArgumentException.class,
+            () -> ChaCha20.decrypt(key, null, data));
+        assertThrows(IllegalArgumentException.class,
+            () -> ChaCha20.decrypt(key, nonce, null));
     }
 
     private static byte[] hexStringToByteArray(String s) {
         int len = s.length();
-        if (len % 2 != 0) throw new IllegalArgumentException("Hex string must have even length");
+        if (len % 2 != 0)
+            throw new IllegalArgumentException("Hex string must have even length");
         byte[] data = new byte[len / 2];
         for (int i = 0; i < len; i += 2) {
             data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
-                    + Character.digit(s.charAt(i + 1), 16));
+                + Character.digit(s.charAt(i + 1), 16));
         }
         return data;
     }