Test native postinc/dec is opted to NQP ops

t/08-performance/02-qast-rewrites.t

@@ -0,0 +1,56 @@
+use lib <t/packages>;
+use Test::Helpers::QAST;
+use Test;
+plan 1;
+
+subtest 'postfix-inc/dec on natives gets overwritten to prefix' => {
+    plan 8;
+    qast-is ｢my int $i; $i++｣, -> \v {
+                qast-contains-op   v, 'add_i'
+        and not qast-contains-call v, '&prefix:<++>'
+        and not qast-contains-call v, '&postfix:<++>'
+    }, 'int, void context ++';
+
+    qast-is ｢my int $i; my int $y; $y = 1 + $i++｣, -> \v {
+                qast-contains-op   v, 'add_i'
+        and not qast-contains-call v, '&prefix:<++>'
+        and not qast-contains-call v, '&postfix:<++>'
+    }, 'int, non-void context ++';
+
+    qast-is ｢my int $i; $i--｣, -> \v {
+                qast-contains-op   v, 'sub_i'
+        and not qast-contains-call v, '&prefix:<-->'
+        and not qast-contains-call v, '&postfix:<-->'
+    }, 'int, void context --';
+
+    qast-is ｢my int $i; my int $y; $y = 1 + $i--｣, -> \v {
+                qast-contains-op   v, 'sub_i'
+        and not qast-contains-call v, '&prefix:<-->'
+        and not qast-contains-call v, '&postfix:<-->'
+    }, 'int, non-void context --';
+
+
+    qast-is ｢my num $i = 2e0; $i++｣, -> \v {
+                qast-contains-op   v, 'add_n'
+        and not qast-contains-call v, '&prefix:<++>'
+        and not qast-contains-call v, '&postfix:<++>'
+    }, 'num, void context ++';
+
+    qast-is ｢my num $i = 2e0; my num $y; $y = 1e0 + $i++｣, -> \v {
+                qast-contains-op   v, 'add_n'
+        and not qast-contains-call v, '&prefix:<++>'
+        and not qast-contains-call v, '&postfix:<++>'
+    }, 'num, non-void context ++';
+
+    qast-is ｢my num $i = 2e0; $i--｣, -> \v {
+                qast-contains-op   v, 'sub_n'
+        and not qast-contains-call v, '&prefix:<-->'
+        and not qast-contains-call v, '&postfix:<-->'
+    }, 'num, void context --';
+
+    qast-is ｢my num $i = 2e0; my int $y; $y = 1e0 + $i--｣, -> \v {
+                qast-contains-op   v, 'sub_n'
+        and not qast-contains-call v, '&prefix:<-->'
+        and not qast-contains-call v, '&postfix:<-->'
+    }, 'num, non-void context --';
+}