1 files changed, 24 insertions, 0 deletions
diff --git a/test/unit/concepts/Cardinality.ml b/test/unit/concepts/Cardinality.ml
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+++ b/test/unit/concepts/Cardinality.ml
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+open Alcotest
+
+module C = Rnt.Concepts.Cardinality
+
+let klass = testable (fun ppf c -> Format.pp_print_string ppf (C.to_string c)) C.equal
+
+let chain () =
+  check bool "empty is least" true (C.leq C.Empty C.Countable);
+  check bool "a tighter ceiling is smaller" true (C.leq (C.Bounded 2) (C.Bounded 5));
+  check bool "a ceiling is finite" true (C.leq (C.Bounded 5) C.Finite);
+  check bool "countable is greatest" true (C.leq C.Finite C.Countable);
+  check bool "and nothing above it" false (C.leq C.Countable C.Finite)
+
+let exhaustion () =
+  check bool "a bounded generator can be exhausted" true (C.exhaustible (C.Bounded 3));
+  check bool "a countable one cannot" false (C.exhaustible C.Countable)
+
+let emptiness () = check klass "a ceiling of zero is emptiness" C.Empty (C.bounded 0)
+
+let suites () =
+  [ ( "concepts/cardinality",
+      [ test_case "chain" `Quick chain;
+        test_case "exhaustion" `Quick exhaustion;
+        test_case "emptiness" `Quick emptiness ] ) ]