tests: unique: test also invalid arguments

Make sure that erlang:unique_integer/1 fails with error:badarg when an
invalid list is given.

Signed-off-by: Davide Bettio <davide@uninstall.it>

Author: bettio

tests/erlang_tests/unique.erl

@@ -20,7 +20,7 @@
 
 -module(unique).
 
--export([start/0]).
+-export([start/0, id/1, check_error/3]).
 
 start() ->
     ok = unique_0(),
@@ -39,6 +39,20 @@ start() ->
     receive_messages(N),
     0.
 
+test_invalid() ->
+    ok = ?MODULE:check_error(fun() -> erlang:unique_integer(?MODULE:id(5)) end),
+    ok = ?MODULE:check_error(fun() -> erlang:unique_integer(?MODULE:id([positive | monotonic])) end).
+
+check_error(F, A, B) ->
+    try F() of
+        Result -> {unexpected, Result}
+    catch
+        A:B -> ok
+    end.
+
+id(X) ->
+    X.
+
 unique_0() ->
     A = erlang:unique_integer(),
     B = erlang:unique_integer(),