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test/response_test.dart

 // Copyright (c) 2014, 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.
 
 library shelf.response_test;
 
 import 'dart:async';
 import 'dart:convert';
 
 import 'package:shelf/shelf.dart' hide Request;
@@ skipping 94 matching lines @@
       expect(copy.encoding, request.encoding);
       expect(copy.context, same(request.context));
 
       controller.add(HELLO_BYTES);
       return new Future(() {
         controller
           ..add(WORLD_BYTES)
           ..close();
       });
     });
+
+
+    test("allows the original response to be read", () {
+      var response = new Response.ok(null);
+      var changed = response.change();
+
+      expect(response.read().toList(), completion(isEmpty));
+      expect(changed.read, throwsStateError);
+    });
+
+    test("allows the changed response to be read", () {
+      var response = new Response.ok(null);
+      var changed = response.change();
+
+      expect(changed.read().toList(), completion(isEmpty));
+      expect(response.read, throwsStateError);
+    });
+
+    test("allows another changed response to be read", () {
+      var response = new Response.ok(null);
+      var changed1 = response.change();
+      var changed2 = response.change();
+
+      expect(changed2.read().toList(), completion(isEmpty));
+      expect(changed1.read, throwsStateError);
+      expect(response.read, throwsStateError);
+    });
   });
 }