add tests for the api

api-proc-macro/tests/test_derive_macro_into_command_definition.rs

@@ -149,3 +149,22 @@ fn test_generic_command() {
     .unwrap();
     assert_eq!(result.a, true);
 }
+
+#[test]
+fn test_unit_command() {
+    #[derive(IntoCommandDefinition)]
+    struct TestStruct;
+
+    let command_definition = TestStruct::create("Test".to_string());
+
+    assert_eq!(command_definition.name, "Test");
+    assert_eq!(command_definition.parameters.capacity(), 0);
+
+    TestStruct::parse(Command {
+        header: CommandHeader {
+            timestamp: Default::default(),
+        },
+        parameters: HashMap::new(),
+    })
+    .unwrap();
+}