pkg/http tweaks

pkg/http/lib/src/multipart_request.dart

Index: pkg/http/lib/src/multipart_request.dart
diff --git a/pkg/http/lib/src/multipart_request.dart b/pkg/http/lib/src/multipart_request.dart
index 051ac76b5701d1054f2cc8791991e7ed44414705..e0c413a66db678560c30e1232eea3142aabb3b3f 100644
--- a/pkg/http/lib/src/multipart_request.dart
+++ b/pkg/http/lib/src/multipart_request.dart
@@ -5,7 +5,6 @@
 library multipart_request;
 
 import 'dart:async';
-import 'dart:io';
 import 'dart:math';
 import 'dart:utf';
 
@@ -36,7 +35,7 @@ class MultipartRequest extends BaseRequest {
   /// The total length of the multipart boundaries used when building the
   /// request body. According to http://tools.ietf.org/html/rfc1341.html, this
   /// can't be longer than 70.
-  static final int _BOUNDARY_LENGTH = 70;
+  static const int _BOUNDARY_LENGTH = 70;
 
   static final Random _random = new Random();
 
@@ -75,7 +74,7 @@ class MultipartRequest extends BaseRequest {
     return length + "--".length + _BOUNDARY_LENGTH + "--\r\n".length;
   }
 
-  set contentLength(int value) {
+  void set contentLength(int value) {
     throw new UnsupportedError("Cannot set the contentLength property of "
         "multipart requests.");
   }
@@ -84,7 +83,7 @@ class MultipartRequest extends BaseRequest {
   /// that will emit the request body.
   ByteStream finalize() {
     // TODO(nweiz): freeze fields and files
-    var boundary = _boundaryString(_BOUNDARY_LENGTH);
+    var boundary = _boundaryString();
     headers['content-type'] = 'multipart/form-data; boundary="$boundary"';
     headers['content-transfer-encoding'] = 'binary';
     super.finalize();
@@ -123,7 +122,7 @@ class MultipartRequest extends BaseRequest {
 
   /// All character codes that are valid in multipart boundaries. From
   /// http://tools.ietf.org/html/rfc2046#section-5.1.1.
-  static final List<int> _BOUNDARY_CHARACTERS = const <int>[
+  static const List<int> _BOUNDARY_CHARACTERS = const <int>[
     39, 40, 41, 43, 95, 44, 45, 46, 47, 58, 61, 63, 48, 49, 50, 51, 52, 53, 54,
     55, 56, 57, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80,
     81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 97, 98, 99, 100, 101, 102, 103,
@@ -157,15 +156,13 @@ class MultipartRequest extends BaseRequest {
     return '$header\r\n\r\n';
   }
 
-  /// Returns a randomly-generated multipart boundary string of the given
-  /// [length].
-  String _boundaryString(int length) {
+  /// Returns a randomly-generated multipart boundary string
+  String _boundaryString() {
     var prefix = "dart-http-boundary-";
-    var list = new List<int>(length - prefix.length);
-    for (var i = 0; i < list.length; i++) {
-      list[i] = _BOUNDARY_CHARACTERS[
-          _random.nextInt(_BOUNDARY_CHARACTERS.length)];
-    }
+    var list = new List<int>.generate(_BOUNDARY_LENGTH - prefix.length,
+        (index) =>
+            _BOUNDARY_CHARACTERS[_random.nextInt(_BOUNDARY_CHARACTERS.length)],
+        growable: false);
     return "$prefix${new String.fromCharCodes(list)}";
   }
 }