fix: method calls were receiving the object reference as the last argument.

The object reference (`self` or `this` in some programming languages) must be the first argument in a method call, but it was the last one.

Author: plusvic

lib/src/compiler/emit.rs

@@ -635,15 +635,16 @@ fn emit_expr(
         },
 
         Expr::FuncCall(func_call) => {
-            // Emit the arguments first.
-            for expr in func_call.args.iter() {
-                emit_expr(ctx, ir, *expr, instr);
-            }
-
+            // If this is method call, the target object (self or this in some
+            // programming languages) is the first argument.
             if let Some(obj) = func_call.object {
                 emit_expr(ctx, ir, obj, instr);
             }
-
+            
+            for expr in func_call.args.iter() {
+                emit_expr(ctx, ir, *expr, instr);
+            }
+            
             if func_call.signature().result_may_be_undef {
                 emit_call_and_handle_undef(
                     ctx,

lib/src/modules/test_proto2/mod.rs

@@ -1,8 +1,9 @@
+use std::rc::Rc;
+
 use crate::modules::prelude::*;
 use crate::modules::protos::test_proto2::NestedProto2;
 use crate::modules::protos::test_proto2::TestProto2;
 use crate::types::Struct;
-use std::rc::Rc;
 
 #[cfg(test)]
 mod tests;
@@ -41,6 +42,25 @@ pub(crate) fn nested_method(
     structure.field_by_name("nested_bool").unwrap().type_value.as_bool()
 }
 
+#[module_export(
+    name = "nested_method_with_arg",
+    method_of = "test_proto2.NestedProto2"
+)]
+pub(crate) fn nested_method_with_arg(
+    ctx: &mut ScanContext,
+    structure: Rc<Struct>,
+    arg: RuntimeString,
+) -> bool {
+    let arg = arg.as_bstr(ctx);
+    let field = structure
+        .field_by_name("nested_string")
+        .unwrap()
+        .type_value
+        .as_string();
+
+    arg.eq(field.as_bstr())
+}
+
 #[module_export]
 pub(crate) fn undef_i64(_ctx: &mut ScanContext) -> Option<i64> {
     None
@@ -126,6 +146,7 @@ fn main(data: &[u8], _meta: Option<&[u8]>) -> TestProto2 {
     nested.set_nested_int32_one(1);
     nested.set_nested_int64_one(1);
     nested.set_nested_bool(false);
+    nested.set_nested_string("foo".to_string());
 
     nested.nested_array_int64.push(1);
     nested.nested_array_int64.push(10);

lib/src/modules/test_proto2/tests/mod.rs

@@ -266,6 +266,12 @@ fn test_proto2_module() {
         "#
     );
 
+    condition_true!(
+        r#"
+        test_proto2.nested.nested_method_with_arg("foo")
+        "#
+    );
+
     condition_true!(
         r#"
         not test_proto2.array_struct[0].nested_method()