Require a digit when parsing JSON number.

tests/utils/src/JsonTest.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.
 
 #library('jsonTest');
 
 #import('dart:json');
 
 main() {
   testEscaping();
@@ skipping 29 matching lines @@
                    JSON.parse(' { "key1" : 1 } '));
 }
 
 void testParseInvalid() {
   void testString(String s) {
     // TODO(ajohnsen): Require JSONParseException exception once all JSON libs
     //                 have been updated.
     Expect.throws(() => JSON.parse(s));
   }
   testString("");
+  testString("-");
+  testString("-.");
   testString("3.a");
   testString("{ key: value }");
   testString("tru");
 
   // Lists
   testString('[, ]');
   testString('["", ]');
   testString('["", "]');
   testString('["" ""]');
 
@@ skipping 36 matching lines @@
   Expect.stringEquals('"\\u001d"', JSON.stringify('\u001d'));
   Expect.stringEquals('"\\u001e"', JSON.stringify('\u001e'));
   Expect.stringEquals('"\\u001f"', JSON.stringify('\u001f'));
   Expect.stringEquals('"\\\""', JSON.stringify('"'));
   Expect.stringEquals('"\\\\"', JSON.stringify('\\'));
   Expect.stringEquals('"Got \\b, \\f, \\n, \\r, \\t, \\u0000, \\\\, and \\"."',
       JSON.stringify('Got \b, \f, \n, \r, \t, \u0000, \\, and ".'));
   Expect.stringEquals('"Got \\b\\f\\n\\r\\t\\u0000\\\\\\"."',
     JSON.stringify('Got \b\f\n\r\t\u0000\\".'));
 }