1 files changed, 35 insertions, 0 deletions
diff --git a/stdlib/source/test/lux/abstract/hash.lux b/stdlib/source/test/lux/abstract/hash.lux
new file mode 100644
index 000000000..f7f82ffe2
--- /dev/null
+++ b/stdlib/source/test/lux/abstract/hash.lux
@@ -0,0 +1,35 @@
+(.module:
+  [lux #*
+   ["_" test (#+ Test)]
+   [abstract
+    [monad (#+ do)]]
+   [data
+    ["." bit ("#@." equivalence)]
+    [number
+     ["n" nat]
+     ["i" int]]]
+   [math
+    ["." random]]]
+  {1
+   ["." /]})
+
+(def: #export test
+  Test
+  (do random.monad
+    [left random.nat
+     right random.int
+     other-left random.nat
+     other-right random.int]
+    (<| (_.covering /._)
+        ($_ _.and
+            (_.cover [/.product]
+                     (and (n.= (:: (/.product n.hash i.hash) hash [left right])
+                               (n.* (:: n.hash hash left)
+                                    (:: i.hash hash right)))
+                          (bit@= (:: (/.product n.hash i.hash) = [left right] [left right])
+                                 (and (:: n.hash = left left)
+                                      (:: i.hash = right right)))
+                          (bit@= (:: (/.product n.hash i.hash) = [left right] [other-left other-right])
+                                 (and (:: n.hash = left other-left)
+                                      (:: i.hash = right other-right)))))
+            ))))