Use official JSON encoding for stream

runtime/vm/json_test.cc

 // 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.
 
 #include "platform/assert.h"
 #include "platform/text_buffer.h"
 #include "vm/json_stream.h"
 #include "vm/unit_test.h"
 #include "vm/dart_api_impl.h"
 
@@ skipping 201 matching lines @@
   EXPECT_STREQ("[\"Hel\\\"\\\"lo\\r\\n\\t\"]", js.ToCString());
 }
 
 
 TEST_CASE(JSON_JSONStream_DartString) {
   const char* kScriptChars =
       "var ascii = 'Hello, World!';\n"
       "var unicode = '\\u00CE\\u00F1\\u0163\\u00E9r\\u00F1\\u00E5\\u0163"
       "\\u00EE\\u00F6\\u00F1\\u00E5\\u013C\\u00EE\\u017E\\u00E5\\u0163"
       "\\u00EE\\u1EDD\\u00F1';\n"
-      "var surrogates = '\\u{1D11E}\\u{1D11E}\\u{1D11E}\\u{1D11E}"
-      "\\u{1D11E}';\n"
+      "var surrogates = '\\u{1D11E}\\u{1D11E}\\u{1D11E}"
+      "\\u{1D11E}\\u{1D11E}';\n"
+      "var wrongEncoding = '\\u{1D11E}' + surrogates[0] + '\\u{1D11E}';"
       "var nullInMiddle = 'This has\\u0000 four words.';";
 
   Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
   EXPECT_VALID(lib);
 
   Dart_Handle result;
   String& obj = String::Handle();
 
   {
     result = Dart_GetField(lib, NewString("ascii"));
@@ skipping 24 matching lines @@
   {
     result = Dart_GetField(lib, NewString("unicode"));
     EXPECT_VALID(result);
     obj ^= Api::UnwrapHandle(result);
 
     JSONStream js;
     {
       JSONObject jsobj(&js);
       EXPECT(!jsobj.AddPropertyStr("unicode", obj));
     }
-    EXPECT_STREQ("{\"unicode\":\"\\u00CE\\u00F1\\u0163\\u00E9r\\u00F1\\u00E5"
-                 "\\u0163\\u00EE\\u00F6\\u00F1\\u00E5\\u013C\\u00EE\\u017E"
-                 "\\u00E5\\u0163\\u00EE\\u1EDD\\u00F1\"}", js.ToCString());
+    EXPECT_STREQ("{\"unicode\":\"Îñţérñåţîöñåļîžåţîờñ\"}", js.ToCString());
   }
 
   {
     result = Dart_GetField(lib, NewString("surrogates"));
     EXPECT_VALID(result);
     obj ^= Api::UnwrapHandle(result);
 
     JSONStream js;
     {
       JSONObject jsobj(&js);
       EXPECT(!jsobj.AddPropertyStr("surrogates", obj));
     }
-    EXPECT_STREQ("{\"surrogates\":\"\\uD834\\uDD1E\\uD834\\uDD1E\\uD834\\uDD1E"
-                 "\\uD834\\uDD1E\\uD834\\uDD1E\"}", js.ToCString());
+    EXPECT_STREQ("{\"surrogates\":\"𝄞𝄞𝄞𝄞𝄞\"}", js.ToCString());
   }
 
   {
+    result = Dart_GetField(lib, NewString("wrongEncoding"));
+    EXPECT_VALID(result);
+    obj ^= Api::UnwrapHandle(result);
+
+    JSONStream js;
+    {
+      JSONObject jsobj(&js);
+      EXPECT(!jsobj.AddPropertyStr("wrongEncoding", obj));
+    }
+    EXPECT_STREQ("{\"wrongEncoding\":\"𝄞\\uD834𝄞\"}", js.ToCString());
+  }
+
+
+  {
     result = Dart_GetField(lib, NewString("nullInMiddle"));
     EXPECT_VALID(result);
     obj ^= Api::UnwrapHandle(result);
 
     JSONStream js;
     {
       JSONObject jsobj(&js);
       EXPECT(!jsobj.AddPropertyStr("nullInMiddle", obj));
     }
     EXPECT_STREQ("{\"nullInMiddle\":\"This has\\u0000 four words.\"}",
@@ skipping 40 matching lines @@
                                &js);
     }
   }
 
   EXPECT_STREQ("{\"test\":[{a, b, c},{a, b, c},{a, b, c}]}", js.ToCString());
 }
 
 #endif  // !PRODUCT
 
 }  // namespace dart