pkg/crypto: move tests to unittest package

pkg/crypto/lib/src/hmac.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of crypto;
 
 /**
  * Hash-based Message Authentication Code support.
  *
  * The [add] method is used to add data to the message. The [digest] and
  * [close] methods are used to extract the message authentication code.
  */
 // TODO(floitsch): make Hash implement Sink, EventSink or similar.
 class HMAC {
+  final List<int> _message;
+  Hash _hash;
+  List<int> _key;
   bool _isClosed = false;
 
   /**
    * Create an [HMAC] object from a [Hash] and a key.
    */
-  HMAC(Hash this._hash, List<int> this._key) : _message = [];
+  HMAC(Hash this._hash, List<int> this._key): _message = [];
 
   /**
    * Add a list of bytes to the message.
    */
   void add(List<int> data) {
     if (_isClosed) throw new StateError("HMAC is closed");
     _message.addAll(data);
   }
 
   /**
@@ skipping 68 matching lines @@
       throw new ArgumentError(
           'Invalid digest size: ${digest.length} in HMAC.verify. '
           'Expected: ${_hash.blockSize}.');
     }
     int result = 0;
     for (var i = 0; i < digest.length; i++) {
       result |= digest[i] ^ computedDigest[i];
     }
     return result == 0;
   }
-
-  // HMAC internal state.
-  Hash _hash;
-  List<int> _key;
-  final List<int> _message;
 }