core/codegen/expr: Implement vararg handling in gen_call

nac3core/src/codegen/expr.rs

@@ -766,6 +766,9 @@ pub fn gen_call<'ctx, G: CodeGenerator>(
     let param_vals;
     let is_extern;
 
+    // Ensure that the function object only contains up to 1 vararg parameter
+    debug_assert!(fun.0.args.iter().filter(|arg| arg.is_vararg).count() <= 1);
+
     let symbol = {
         // make sure this lock guard is dropped at the end of this scope...
         let def = definition.read();
@@ -782,18 +785,46 @@ pub fn gen_call<'ctx, G: CodeGenerator>(
                 is_extern = instance_to_stmt.is_empty();
                 let old_key = ctx.get_subst_key(obj.as_ref().map(|a| a.0), fun.0, None);
                 let mut keys = fun.0.args.clone();
-                let mut mapping = HashMap::new();
+                let mut mapping = HashMap::<_, Vec<ValueEnum>>::new();
+
                 for (key, value) in params {
-                    mapping.insert(key.unwrap_or_else(|| keys.remove(0).name), value);
+                    // Find the matching argument
+                    let matching_param = fun
+                        .0
+                        .args
+                        .iter()
+                        .find_or_last(|p| key.is_some_and(|k| k == p.name))
+                        .unwrap();
+                    if matching_param.is_vararg {
+                        if key.is_none() && !keys.is_empty() {
+                            keys.remove(0);
+                        }
+
+                        if let Some(param) = mapping.get_mut(&matching_param.name) {
+                            param.push(value);
+                        } else {
+                            mapping.insert(key.unwrap_or(matching_param.name), vec![value]);
+                        }
+                    } else {
+                        mapping.insert(key.unwrap_or_else(|| keys.remove(0).name), vec![value]);
+                    }
                 }
+
                 // default value handling
                 for k in keys {
                     if mapping.contains_key(&k.name) {
                         continue;
                     }
+
                     mapping.insert(
                         k.name,
-                        ctx.gen_symbol_val(generator, &k.default_value.unwrap(), k.ty).into(),
+                        if k.is_vararg {
+                            Vec::default()
+                        } else {
+                            vec![ctx
+                                .gen_symbol_val(generator, &k.default_value.unwrap(), k.ty)
+                                .into()]
+                        },
                     );
                 }
                 // reorder the parameters
@@ -804,13 +835,15 @@ pub fn gen_call<'ctx, G: CodeGenerator>(
                     .map(|arg| (mapping.remove(&arg.name).unwrap(), arg.ty))
                     .collect_vec();
                 if let Some(obj) = &obj {
-                    real_params.insert(0, (obj.1.clone(), obj.0));
+                    real_params.insert(0, (vec![obj.1.clone()], obj.0));
                 }
                 let static_params = real_params
                     .iter()
                     .enumerate()
                     .filter_map(|(i, (v, _))| {
-                        if let ValueEnum::Static(s) = v {
+                        if v.len() != 1 {
+                            None
+                        } else if let ValueEnum::Static(s) = &v[0] {
                             Some((i, s.clone()))
                         } else {
                             None
@@ -840,8 +873,13 @@ pub fn gen_call<'ctx, G: CodeGenerator>(
                 };
                 param_vals = real_params
                     .into_iter()
-                    .map(|(p, t)| p.to_basic_value_enum(ctx, generator, t))
+                    .map(|(ps, t)| {
-                    .collect::<Result<Vec<_>, String>>()?;
+                        ps.into_iter().map(|p| p.to_basic_value_enum(ctx, generator, t)).collect()
+                    })
+                    .collect::<Result<Vec<Vec<_>>, _>>()?
+                    .into_iter()
+                    .flatten()
+                    .collect::<Vec<_>>();
                 instance_to_symbol.get(&key).cloned().ok_or_else(String::new)
             }
             TopLevelDef::Class { .. } => {