Add type argument test

dust-lang/src/abstract_tree/function_call.rs

@@ -134,8 +134,8 @@ impl AbstractNode for FunctionCall {
                 .map(|r#type| r#type.node.clone())
                 .zip(self.type_arguments.into_iter().map(|r#type| r#type.node))
             {
-                if let Type::Argument(identifier) = type_parameter {
-                    function_context.set_type(identifier, type_argument)?;
+                if let Type::Argument(identifier, r#type) = type_parameter {
+                    function_context.set_type(identifier, *r#type)?;
                 }
             }
         };

dust-lang/src/abstract_tree/type.rs

@@ -13,7 +13,7 @@ use super::{AbstractNode, Action, WithPosition};
 #[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Ord)]
 pub enum Type {
     Any,
-    Argument(Identifier),
+    Argument(Identifier, Box<Type>),
     Boolean,
     Float,
     Function {
@@ -191,7 +191,7 @@ impl Display for Type {
                 write!(f, ") : {}", return_type.node)
             }
             Type::Structure { name, .. } => write!(f, "{name}"),
-            Type::Argument(identifier) => write!(f, "{identifier}"),
+            Type::Argument(identifier, _type) => write!(f, "{identifier}"),
         }
     }
 }

dust-lang/tests/functions.rs

@@ -4,7 +4,19 @@ use dust_lang::{
     *,
 };
 
-use dust_lang::interpret;
+#[test]
+fn function_call_with_type_argument() {
+    assert_eq!(
+        interpret(
+            "test",
+            "
+            foobar = (T)(x : T) T { x }
+            foobar::(int)::(42)
+            ",
+        ),
+        Ok(Some(Value::integer(42)))
+    );
+}
 
 #[test]
 fn function_call() {