add functional test for qualifying issue #1

test/dune

@@ -0,0 +1,4 @@
+(tests
+ (names testrange)
+ (libraries oUnit range)
+ (action (run %{test})))

test/testrange.ml

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+open OUnit2
+open Base
+
+
+let equality_tests = 
+[
+  ("Issue #1 : Modified range can be equal to a natural one" >:: fun _ctxt ->
+    let data_a = Range.from 3 6 in
+    let data_b = Range.from 2 5 |> Range.map Int.succ in
+    assert_bool "equality failed" (Range.equal data_a data_b)
+  )
+]
+
+let non_reg_tests = [
+    equality_tests
+] |> List.concat
+
+
+let () = 
+  "Range non regression bug testing" >::: non_reg_tests |> run_test_tt_main