ffi(test_error_handling): fix UB by matching extern "C" signature and using valid FFINetwork; move invalid raw-value testing to C-side

Author: PastaPastaPasta

dash-spv-ffi/tests/unit/test_error_handling.rs

@@ -173,19 +173,10 @@ mod tests {
 
     #[test]
     fn test_invalid_enum_handling() {
-        // Test with invalid network value
-        // Since we can't safely create an invalid enum in Rust, we'll test the C API
-        // by calling it with a raw value that doesn't correspond to any valid variant
+        // Use a valid enum value to avoid UB in Rust tests. If invalid raw inputs
+        // need to be tested, do so from a C test or add a raw-int FFI entrypoint.
         unsafe {
-            // dash_spv_ffi_config_new expects FFINetwork but we'll cast an invalid i32
-            // This simulates what could happen from C code
-            let config = {
-                extern "C" {
-                    fn dash_spv_ffi_config_new(network: i32) -> *mut std::ffi::c_void;
-                }
-                dash_spv_ffi_config_new(999) as *mut FFIClientConfig
-            };
-            // Should still create a config (defaults to Dash)
+            let config = dash_spv_ffi_config_new(FFINetwork::Dash);
             assert!(!config.is_null());
             dash_spv_ffi_config_destroy(config);
         }