adding number of args check and avoiding compiler warnings

Author: marcomq

src/py_lib.rs

@@ -63,6 +63,28 @@ pub fn register_function_str(fn_name: String, number_of_args: Option<u8>) -> cra
             .globals
             .get_item(&fn_name, vm)
             .expect(&format!("Function {fn_name} not found"));
+
+        if let Some(num_args) = number_of_args {
+            let py_analyze_sig = format!(
+                r#"
+from inspect import signature
+if len(signature({}).parameters) != {}:
+    raise Exception("Function parameters don't match in 'registerFunction'")
+"#,
+                fn_name, num_args
+            );
+
+            let code_obj = vm
+                .compile(
+                    &py_analyze_sig,
+                    rustpython_vm::compiler::Mode::Exec,
+                    "<embedded>".to_owned(),
+                )
+                .map_err(|err| vm.new_syntax_error(&err, Some(&py_analyze_sig)))?;
+            vm.run_code_obj(code_obj, GLOBALS.clone()).expect(&format!(
+                "Number of args doesn't match signature of {fn_name}."
+            ));
+        }
         FUNCTION_MAP.lock().unwrap().insert(fn_name);
         Ok(())
     })

src/py_lib_pyo3.rs

@@ -76,11 +76,10 @@ pub fn register_function_str(fn_name: String, number_of_args: Option<u8>) -> cra
         if let Some(num_args) = number_of_args {
             let py_analyze_sig = format!(
                 r#"
-if True:
-    from inspect import signature
-    if len(signature({}).parameters) != {}:
-        raise Exception("Function parameters don't match in 'registerFunction'")
-    "#,
+from inspect import signature
+if len(signature({}).parameters) != {}:
+    raise Exception("Function parameters don't match in 'registerFunction'")
+"#,
                 fn_name, num_args
             );
             let code_c = CString::new(py_analyze_sig).expect("CString::new failed");