Fix incorrect attribute name in X::AdHoc.new

- Partially phixes #1266
- Includes todoed test that still wants to be told
    what the better message is

src/core/IO/Socket/Async.pm

@@ -198,7 +198,7 @@ my class IO::Socket::Async {
                                 # do nothing
                             }
                             elsif err {
-                                quit(X::AdHoc.new(message => err));
+                                quit(X::AdHoc.new(payload => err));
                                 $finished = 1;
                             }
                             else {

t/05-messages/02-errors.t

@@ -2,7 +2,7 @@ use lib <t/packages/>;
 use Test;
 use Test::Helpers;
 
-plan 2;
+plan 3;
 
 # RT #132295
 
@@ -16,4 +16,12 @@ throws-like { for [:a] X [:b] -> ($i, $j) { } },
     message => / '<anon>' /,
     "anonymous subs get '<anon>' in arity error messages";
 
+todo 'needs better error message';
+throws-like {
+    sub l { IO::Socket::Async.listen: "localhost", 111390 }
+    react whenever l() {
+        whenever l() {} # try to listen on already open sock
+    }
+}, X::AdHoc, message => /'something good'/
+
 # vim: ft=perl6 expandtab sw=4