Throw FormatException when Int32/Int64.parseRadix() encounters bad digit

pkg/fixnum/test/int_64_test.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 int64test;
 import 'package:fixnum/fixnum.dart';
 import 'package:unittest/unittest.dart';
 
 void main() {
   group("is-tests", () {
@@ skipping 640 matching lines @@
       checkInt(12345678);
       checkInt(-12345678);
       checkInt(2147483647);
       checkInt(2147483648);
       checkInt(-2147483647);
       checkInt(-2147483648);
       checkInt(4294967295);
       checkInt(4294967296);
       checkInt(-4294967295);
       checkInt(-4294967296);
+      expect(() => Int64.parseRadix('xyzzy', -1), throwsArgumentError);
+      expect(() => Int64.parseRadix('plugh', 10),
+          throwsA(new isInstanceOf<FormatException>()));
     });
 
     test("parseRadix", () {
       check(String s, int r, String x) {
         expect(Int64.parseRadix(s, r).toString(), x);
       }
       check('ghoul', 36, '27699213');
       check('ghoul', 35, '24769346');
       // Min and max value.
       check("-9223372036854775808", 10, "-9223372036854775808");
@@ skipping 71 matching lines @@
       expect(Int64.MAX_VALUE.toRadixString(10), "9223372036854775807");
       expect(Int64.MAX_VALUE.toRadixString(11), "1728002635214590697");
       expect(Int64.MAX_VALUE.toRadixString(12), "41a792678515120367");
       expect(Int64.MAX_VALUE.toRadixString(13), "10b269549075433c37");
       expect(Int64.MAX_VALUE.toRadixString(14), "4340724c6c71dc7a7");
       expect(Int64.MAX_VALUE.toRadixString(15), "160e2ad3246366807");
       expect(Int64.MAX_VALUE.toRadixString(16), "7fffffffffffffff");
     });
   });
 }