pkg/crypto: tighten up

pkg/crypto/lib/src/hash_utils.dart

Index: pkg/crypto/lib/src/hash_utils.dart
diff --git a/pkg/crypto/lib/src/hash_utils.dart b/pkg/crypto/lib/src/hash_utils.dart
index 713dbb9d2cd0ce6f8475bb1de5a87de16eb3ea73..84df9d0e4826edde02f9764f52f43423bcbab6a6 100644
--- a/pkg/crypto/lib/src/hash_utils.dart
+++ b/pkg/crypto/lib/src/hash_utils.dart
@@ -22,16 +22,17 @@ int _rotl32(int val, int shift) {
 // Base class encapsulating common behavior for cryptographic hash
 // functions.
 abstract class _HashBase implements Hash {
-  _HashBase(int this._chunkSizeInWords,
-            int this._digestSizeInWords,
+  _HashBase(int chunkSizeInWords,
+            int digestSizeInWords,
             bool this._bigEndianWords)
-      : _pendingData = [] {
-    _currentChunk = new List(_chunkSizeInWords);
-    _h = new List(_digestSizeInWords);
-  }
+      : _pendingData = [],
+        _currentChunk = new List(chunkSizeInWords),
+        _h = new List(digestSizeInWords),
+        _chunkSizeInWords = chunkSizeInWords,
+        _digestSizeInWords = digestSizeInWords;
 
   // Update the hasher with more data.
-  add(List<int> data) {
+  void add(List<int> data) {
     if (_digestCalled) {
       throw new StateError(
           'Hash update method called after digest was retrieved');
@@ -58,18 +59,15 @@ abstract class _HashBase implements Hash {
     return _chunkSizeInWords * _BYTES_PER_WORD;
   }
 
-  // Create a fresh instance of this Hash.
-  newInstance();
-
   // One round of the hash computation.
-  _updateHash(List<int> m);
+  void _updateHash(List<int> m);
 
   // Helper methods.
-  _add32(x, y) => (x + y) & _MASK_32;
-  _roundUp(val, n) => (val + n - 1) & -n;
+  int _add32(x, y) => (x + y) & _MASK_32;
+  int _roundUp(val, n) => (val + n - 1) & -n;
 
   // Compute the final result as a list of bytes from the hash words.
-  _resultAsBytes() {
+  List<int> _resultAsBytes() {
     var result = [];
     for (var i = 0; i < _h.length; i++) {
       result.addAll(_wordToBytes(_h[i]));
@@ -78,7 +76,7 @@ abstract class _HashBase implements Hash {
   }
 
   // Converts a list of bytes to a chunk of 32-bit words.
-  _bytesToChunk(List<int> data, int dataIndex) {
+  void _bytesToChunk(List<int> data, int dataIndex) {
     assert((data.length - dataIndex) >= (_chunkSizeInWords * _BYTES_PER_WORD));
 
     for (var wordIndex = 0; wordIndex < _chunkSizeInWords; wordIndex++) {
@@ -96,7 +94,7 @@ abstract class _HashBase implements Hash {
   }
 
   // Convert a 32-bit word to four bytes.
-  _wordToBytes(int word) {
+  List<int> _wordToBytes(int word) {
     List<int> bytes = new List(_BYTES_PER_WORD);
     bytes[0] = (word >> (_bigEndianWords ? 24 : 0)) & _MASK_8;
     bytes[1] = (word >> (_bigEndianWords ? 16 : 8)) & _MASK_8;
@@ -107,7 +105,7 @@ abstract class _HashBase implements Hash {
 
   // Iterate through data updating the hash computation for each
   // chunk.
-  _iterate() {
+  void _iterate() {
     var len = _pendingData.length;
     var chunkSizeInBytes = _chunkSizeInWords * _BYTES_PER_WORD;
     if (len >= chunkSizeInBytes) {
@@ -122,7 +120,7 @@ abstract class _HashBase implements Hash {
 
   // Finalize the data. Add a 1 bit to the end of the message. Expand with
   // 0 bits and add the length of the message.
-  _finalizeData() {
+  void _finalizeData() {
     _pendingData.add(0x80);
     var contentsLength = _lengthInBytes + 9;
     var chunkSizeInBytes = _chunkSizeInWords * _BYTES_PER_WORD;
@@ -148,7 +146,7 @@ abstract class _HashBase implements Hash {
   final bool _bigEndianWords;
   int _lengthInBytes = 0;
   List<int> _pendingData;
-  List<int> _currentChunk;
-  List<int> _h;
+  final List<int> _currentChunk;
+  final List<int> _h;
   bool _digestCalled = false;
 }