[v.6 REVIEW] Improve DateTime subclass tests

- Use proper test routines
- Test type of created object
- Lexicalize the test class

Orig: e1449d6

Author: zoffixznet

S32-temporal/Date.t

@@ -3,7 +3,7 @@ use Test;
 
 # L<S32::Temporal/C<Date>>
 
-plan 116;
+plan 122;
 
 # construction
 {
@@ -176,13 +176,15 @@ is Date.new('2015-12-29',:formatter({sprintf "%2d/%2d/%4d",.day,.month,.year})),
 }
 
 {
-    class FooDate is Date { has $.foo };
+    my class FooDate is Date { has $.foo };
     for (2016,2,20), '2016-02-20', \(:2016year,:2month,:20day) -> $date {
         my $fd = FooDate.new(|$date, foo => 42);
-        is $fd.year, 2016, "is year in FooDate ok";
-        is $fd.month,   2, "is month in FooDate ok";
-        is $fd.day,    20, "is day in FooDate ok";
-        is $fd.foo,    42, "is foo in FooDate ok";
+        isa-ok    $fd, FooDate,   'created object is of right type';
+        isa-ok    $fd, Date,      'created object is a subclass';
+        is-deeply $fd.year, 2016, 'is year in FooDate ok';
+        is-deeply $fd.month,   2, 'is month in FooDate ok';
+        is-deeply $fd.day,    20, 'is day in FooDate ok';
+        is-deeply $fd.foo,    42, 'is foo in FooDate ok';
     }
 }