Add tests for "is_cached"

S02-names/is_cached.t

@@ -0,0 +1,22 @@
+use v6;
+use Test;
+
+plan 6;
+
+#?pugs   skip "is cached NYI"
+#?niecza skip "is cached NYI"
+{
+    my @seen;
+    sub fib(Int $x) is cached {
+        @seen.push: $x;
+        $x <= 1 ?? 1 !! fib($x - 1) + fib($x - 2);
+    }
+    is fib(9), 55, 'does fib(9) work';
+    is @seen, (9,8,7,6,5,4,3,2,1,0), 'did we call them all (1)';
+    is fib(10), 89, 'does fib(10) work';
+    is @seen, (9,8,7,6,5,4,3,2,1,0,10), 'did we call them all (2)';
+    is fib(10), 89, 'does fib(10) work';
+    is @seen, (9,8,7,6,5,4,3,2,1,0,10), 'did we call them all (3)';
+} #6
+
+# vim: ft=perl6