Refactor bitwise operations for clarity in cipher algorithms and tests

- Updated bitwise checks in AEADCipher, AES decryption modes, and AES cache generation to use parentheses for improved readability.
- Enhanced tests for ChaCha20, Salsa20, XChaCha20, and XSalsa20 to validate output consistency with random nonces.
- Added handling for non-list iterables in the toUint8List function, including support for Set and Queue types.

Author: dipu-bd

lib/src/algorithms/aead_cipher.dart

@@ -67,7 +67,7 @@ class AEADCipher<C extends Cipher, M extends MACHashBase> implements Cipher {
 
     if (aad != null) {
       sink.add(aad);
-      if (aad.length & 15 != 0) {
+      if ((aad.length & 15) != 0) {
         sink.add(Uint8List(16 - (aad.length & 15))); // pad with zero
       }
     }
@@ -82,7 +82,7 @@ class AEADCipher<C extends Cipher, M extends MACHashBase> implements Cipher {
     final sink = _createSink(aad);
 
     sink.add(data);
-    if (dataLength & 15 != 0) {
+    if ((dataLength & 15) != 0) {
       sink.add(Uint8List(16 - (dataLength & 15))); // pad with zero
     }
 
@@ -155,7 +155,7 @@ class AEADStreamCipher<C extends StreamCipher, M extends MACHashBase>
 
   @override
   StreamTransformer<RS, RT> cast<RS, RT>() {
-    throw UnsupportedError('AEADCipher does not allow casting');
+    throw UnsupportedError('AEADStreamCipher does not allow casting');
   }
 
   /// Generates a message authentication tag for a [stream] of data.
@@ -182,7 +182,7 @@ class AEADStreamCipher<C extends StreamCipher, M extends MACHashBase>
           output.add(data);
         },
         onDone: () {
-          if (dataLength & 15 != 0) {
+          if ((dataLength & 15) != 0) {
             sink.add(Uint8List(16 - (dataLength & 15))); // pad with zero
           }
           sink.add(AEADCipher._build128(dataLength, aadLength));
@@ -222,7 +222,7 @@ class AEADStreamCipher<C extends StreamCipher, M extends MACHashBase>
       dataLength += data.length;
       sink.add(data);
     }
-    if (dataLength & 15 != 0) {
+    if ((dataLength & 15) != 0) {
       sink.add(Uint8List(16 - (dataLength & 15))); // pad with zero
     }
 

lib/src/algorithms/aes_modes/cbc.dart

@@ -145,7 +145,7 @@ class AESInCBCModeDecrypt extends Cipher with SaltedCipher {
     final output32 = Uint32List.view(output.buffer);
     final xkey32 = AESCore.$expandDecryptionKey(key32);
 
-    if (n & 15 != 0) {
+    if ((n & 15) != 0) {
       throw StateError('Invalid input size');
     }
 

lib/src/algorithms/aes_modes/ecb.dart

@@ -121,7 +121,7 @@ class AESInECBModeDecrypt extends Cipher {
     final output32 = Uint32List.view(output.buffer);
     final xkey32 = AESCore.$expandDecryptionKey(key32);
 
-    if (n & 15 != 0) {
+    if ((n & 15) != 0) {
       throw StateError('Invalid input size');
     }
 

lib/src/algorithms/aes_modes/ige.dart

@@ -166,7 +166,7 @@ class AESInIGEModeDecrypt extends Cipher with SaltedCipher {
     final output32 = Uint32List.view(output.buffer);
     final xkey32 = AESCore.$expandDecryptionKey(key32);
 
-    if (n & 15 != 0) {
+    if ((n & 15) != 0) {
       throw StateError('Invalid input size');
     }
 

lib/src/algorithms/aes_modes/pcbc.dart

@@ -157,7 +157,7 @@ class AESInPCBCModeDecrypt extends Cipher with SaltedCipher {
     final output32 = Uint32List.view(output.buffer);
     final xkey32 = AESCore.$expandDecryptionKey(key32);
 
-    if (n & 15 != 0) {
+    if ((n & 15) != 0) {
       throw StateError('Invalid input size');
     }
 

test/chacha20_test.dart

@@ -73,7 +73,11 @@ void main() {
     test('random nonce is used if nonce is null, ', () {
       var key = randomNumbers(32);
       var text = randomBytes(100);
-      chacha20(text, key);
+      var out = chacha20(text, key);
+      expect(out, isNotEmpty);
+      expect(out, isNot(equals(text)));
+      var out2 = chacha20(out, key);
+      expect(out2, isNot(equals(out)));
     });
   });
 

test/salsa20_poly1305_test.dart

@@ -57,7 +57,11 @@ void main() {
     test('random nonce is used if nonce is null, ', () {
       var key = randomNumbers(32);
       var text = randomBytes(100);
-      salsa20poly1305(text, key);
+      var out = salsa20poly1305(text, key);
+      expect(out.data, isNotEmpty);
+      expect(out.data, isNot(equals(text)));
+      var out2 = salsa20poly1305(text, key);
+      expect(out2, isNot(equals(out)));
     });
     test('reset iv', () {
       var x = Salsa20(Uint8List(32)).poly1305();

test/salsa20_test.dart

@@ -60,7 +60,11 @@ void main() {
     test('random nonce is used if nonce is null, ', () {
       var key = randomNumbers(32);
       var text = randomBytes(100);
-      salsa20(text, key);
+      var out = salsa20(text, key);
+      expect(out, isNotEmpty);
+      expect(out, isNot(equals(text)));
+      var out2 = salsa20(text, key);
+      expect(out2, isNot(equals(out)));
     });
   });
 

test/typed_data_test.dart

@@ -1,6 +1,7 @@
 // Copyright (c) 2024, Sudipto Chandra
 // All rights reserved. Check LICENSE file for details.
 
+import 'dart:collection';
 import 'dart:typed_data';
 
 import 'package:cipherlib/cipherlib.dart';
@@ -46,11 +47,16 @@ void main() {
       expect(out[0], equals(2));
     });
 
-    test('toUint8List handles non-list iterables', () {
+    test('toUint8List handles non-list iterables of type Set', () {
       final out = toUint8List({1, 2, 3, 4});
       expect(out, equals(Uint8List.fromList([1, 2, 3, 4])));
     });
 
+    test('toUint8List handles non-list iterables of type Queue', () {
+      final out = toUint8List(Queue<int>.from([1, 2, 3, 4]));
+      expect(out, equals(Uint8List.fromList([1, 2, 3, 4])));
+    });
+
     test('toUint8List returns same instance for full Uint8List buffer', () {
       final full = Uint8List.fromList(List.generate(8, (i) => i));
       final out = toUint8List(full);

test/xchacha20_poly1305_test.dart

@@ -67,7 +67,11 @@ void main() {
     test('random nonce is used if nonce is null', () {
       var key = randomNumbers(32);
       var text = randomBytes(100);
-      xchacha20poly1305(text, key);
+      var out = xchacha20poly1305(text, key);
+      expect(out.data, isNotEmpty);
+      expect(out.data, isNot(equals(text)));
+      var out2 = xchacha20poly1305(text, key);
+      expect(out2, isNot(equals(out)));
     });
     test('subkey is same as internal key', () {
       var x = XChaCha20(Uint8List(32)).poly1305();