Add test for global variables

test/c/ffi_test.c

@@ -26,7 +26,7 @@ CString upcall_test(StringFactory fun) {
     return fun();
 }
 
-static int counter = 0;
+int counter = 0;
 
 static char* responses[] = { "Hello, world!", "Goodbye friend.", "co'oi prenu" };
 

test/clj/coffi/ffi_test.clj

@@ -44,3 +44,8 @@
            {:a \x
             :x 3.14
             :y 42.0})))
+
+(t/deftest static-variables-are-mutable
+  (ffi/freset! (ffi/static-variable "counter" ::mem/int) 1)
+  (t/is (= ((ffi/cfn "get_string1" [] ::mem/c-string))
+           "Goodbye friend.")))