1 files changed, 22 insertions, 0 deletions
diff --git a/new-luxc/test/test/luxc/parser.lux b/new-luxc/test/test/luxc/parser.lux
index 7a0b2c278..4c1b65584 100644
--- a/new-luxc/test/test/luxc/parser.lux
+++ b/new-luxc/test/test/luxc/parser.lux
@@ -84,6 +84,28 @@
           (:: code;Eq<Code> = parsed sample))
         ))
 
+(def: nat-to-frac
+  (-> Nat Frac)
+  (|>. nat-to-int int-to-frac))
+
+(context: "Frac special syntax."
+  [numerator (|> r;nat (:: @ map (|>. (n.% +100) nat-to-frac)))
+   denominator (|> r;nat (:: @ map (|>. (n.% +100) (n.max +1) nat-to-frac)))
+   signed? r;bool
+   #let [expected (|> numerator (f./ denominator) (f.* (if signed? -1.0 1.0)))]]
+  (test "Can parse frac ratio syntax."
+        (case (&;parse [default-cursor
+                        (format (if signed? "-" "")
+                                (%i (frac-to-int numerator))
+                                "/"
+                                (%i (frac-to-int denominator)))])
+          (#R;Success [_ [_ (#;Frac actual)]])
+          (f.= expected actual)
+
+          _
+          false)
+        ))
+
 (def: comment-text^
   (r;Random Text)
   (let [char-gen (|> r;nat (r;filter (function [value]