Add argument error for int.parse(null).

runtime/lib/integers_patch.dart

Index: runtime/lib/integers_patch.dart
diff --git a/runtime/lib/integers_patch.dart b/runtime/lib/integers_patch.dart
index 4ac46dc74ce7d8a629ff4fac86102ad09ea1a839..c49dbf3c107700f6c3a62b05ccd6e3a842d71d34 100644
--- a/runtime/lib/integers_patch.dart
+++ b/runtime/lib/integers_patch.dart
@@ -22,17 +22,17 @@ patch class int {
         return null;  // Empty.
       }
     }
-    int smiLimit = is64Bit() ? 18 : 9;
+    var smiLimit = is64Bit() ? 18 : 9;
     if ((last - ix) >= smiLimit) {
       return null;  // May not fit into a Smi.
     }
     var result = 0;
     for (int i = ix; i <= last; i++) {
-      var c = str.codeUnitAt(i) - 0x30;
-      if ((c > 9) || (c < 0)) {
+      var c = 0x30 ^ str.codeUnitAt(i);
+      if (9 < c) {
         return null;
       }
-      result = result * 10 + c;
+      result = 10 * result + c;
     }
     return sign * result;
   }
@@ -62,6 +62,7 @@ patch class int {
   /* patch */ static int parse(String source,
                                { int radix,
                                  int onError(String str) }) {
+    if (identical(source, null)) throw new ArgumentError(source);

[srdjan, 2014/09/17 15:13:53]

Please explain why you are using identical instead of ==.

[Lasse Reichstein Nielsen, 2014/09/17 15:28:04]

Ack, a silly attempt to see if it made any difference (it didn't), but I forgot
to roll it back.
I'll undo that.

     if (radix == null) {
       int result;
       if (source.isNotEmpty) result = _parse(source);