From b83c4bb0cc6e410d96a1a99332ad124cae089ed3 Mon Sep 17 00:00:00 2001
From: Shautvast <shautvast@gmail.com>
Date: Mon, 10 Nov 2025 15:24:31 +0100
Subject: [PATCH] type checking on constructor arguments

---
 src/bytecode_compiler.rs | 30 +++++++++++-------------------
 src/compiler_tests.rs    | 15 +++++++++++++++
 src/vm.rs                | 13 +++++++++++--
 3 files changed, 37 insertions(+), 21 deletions(-)

diff --git a/src/bytecode_compiler.rs b/src/bytecode_compiler.rs
index 796cb00..60949e4 100644
--- a/src/bytecode_compiler.rs
+++ b/src/bytecode_compiler.rs
@@ -160,21 +160,6 @@ impl Compiler {
         registry: &mut HashMap<String, Chunk>,
     ) -> Result<(), CompilerErrorAtLine> {
         match expression {
-            // Expression::FunctionCall {
-            //     name, arguments, ..
-            // } => {
-            //     let qname = format!("{}.{}", namespace, name);
-            //     let name_index = self
-            //         .chunk
-            //         .find_constant(&qname)
-            //         .unwrap_or_else(|| self.chunk.add_constant(Value::String(qname)));
-            //
-            //     for argument in arguments {
-            //         self.compile_expression(namespace, argument, registry)?;
-            //     }
-            //     self.emit_bytes(OP_CALL, name_index as u16);
-            //     self.emit_byte(arguments.len() as u16);
-            // }
             Expression::FunctionCall {
                 name, arguments, ..
             } => {
@@ -281,7 +266,9 @@ impl Compiler {
                 }
             }
             Expression::Stop { .. } => {}
-            NamedParameter { value,.. } => {self.compile_expression(namespace, value, symbols, registry)?}
+            NamedParameter { value, .. } => {
+                self.compile_expression(namespace, value, symbols, registry)?
+            }
             Expression::ListGet { index, list } => {
                 self.compile_expression(namespace, list, symbols, registry)?;
                 self.compile_expression(namespace, index, symbols, registry)?;
@@ -305,10 +292,15 @@ impl Compiler {
     ) -> Result<(), CompilerErrorAtLine> {
         for parameter in parameters {
             for argument in arguments {
-                if let NamedParameter { name, .. } = argument {
+                if let NamedParameter { name, value, .. } = argument {
                     if name.lexeme == parameter.name.lexeme {
-                        self.compile_expression(namespace, argument, symbols, registry)?;
-                        break;
+                        let value_type = infer_type(value, symbols);
+                        if parameter.var_type != value_type {
+                            return Err(CompilerErrorAtLine::raise(CompilerError::IncompatibleTypes(parameter.var_type.clone(), value_type), argument.line()));
+                        } else {
+                            self.compile_expression(namespace, argument, symbols, registry)?;
+                            break;
+                        }
                     }
                 } else {
                     self.compile_expression(namespace, argument, symbols, registry)?;
diff --git a/src/compiler_tests.rs b/src/compiler_tests.rs
index e225127..bd2bf12 100644
--- a/src/compiler_tests.rs
+++ b/src/compiler_tests.rs
@@ -147,6 +147,21 @@ p"#);
         );
     }
 
+    #[test]
+    fn declare_and_instantiate_object_wrong_type() {
+        let r = run(r#"
+object Person:
+   name: string
+
+let p = Person(name: 0x42)
+p"#);
+        assert!(r.is_err());
+        assert_eq!(
+            r#"Compilation failed: error at line 5, Expected string, found integer"#,
+            format!("{}", r.unwrap_err().to_string())
+        );
+    }
+
     #[test]
     fn literal_map() {
         let result = run(r#"{"name": "Dent", "age": 40 }"#);
diff --git a/src/vm.rs b/src/vm.rs
index e515b34..8a96f34 100644
--- a/src/vm.rs
+++ b/src/vm.rs
@@ -220,11 +220,20 @@ impl Vm {
 
                         if let Some(params) = constructor {
                             if params.len() != args.len() {
-                                return Err(RuntimeError::IllegalArgumentsException(function_name, params.len(), args.len()));
+                                return Err(RuntimeError::IllegalArgumentsException(
+                                    function_name,
+                                    params.len(),
+                                    args.len(),
+                                ));
                             }
 
                             let mut fields = vec![];
-                            params.iter().zip(args.into_iter()).for_each(|(param, arg)| {fields.push((param.name.lexeme.clone(), arg))});
+                            params
+                                .iter()
+                                .zip(args.into_iter())
+                                .for_each(|(param, arg)| {
+                                    fields.push((param.name.lexeme.clone(), arg))
+                                });
                             let new_instance = Value::ObjectType(Box::new(Object {
                                 definition: function_name,
                                 fields,