From bf91985e00832adfcd316ea15627a02c88a6beb5 Mon Sep 17 00:00:00 2001
From: bog <bog@gozmail.net>
Date: Sun, 18 Feb 2024 11:35:33 +0100
Subject: [PATCH] :bug: type checking of overloaded functions.

---
 lang/src/sym_table.c     | 24 +++++++++++++++++++-----
 lang/src/sym_table.h     |  1 +
 lang/src/type_checker.c  | 13 +++++++++++--
 lang/src/type_resolver.c | 14 ++++++++++++++
 4 files changed, 45 insertions(+), 7 deletions(-)

diff --git a/lang/src/sym_table.c b/lang/src/sym_table.c
index b5e45fe..17d109b 100644
--- a/lang/src/sym_table.c
+++ b/lang/src/sym_table.c
@@ -12,6 +12,12 @@ void sym_table_init(struct sym_table* self, struct sym_table* prev)
   self->addr_counter = 0;
 
   self->prev = prev;
+  self->next = NULL;
+
+  if (self->prev && self->prev->next == NULL)
+    {
+      self->prev->next = self;
+    }
 }
 
 void sym_table_free(struct sym_table* self)
@@ -96,7 +102,7 @@ struct sym* sym_table_fetch(struct sym_table* self,
 
   if (self->prev)
     {
-      return sym_table_fetch(self->prev, name, NULL);
+      return sym_table_fetch(self->prev, name, type);
     }
 
   return NULL;
@@ -109,8 +115,15 @@ struct sym* sym_table_fetch_fun(struct sym_table* self,
   struct vec args_ty;
   vec_init(&args_ty, 1);
 
+  struct sym_table* itr = self;
+
+  while (itr->next)
+    {
+      itr = itr->next;
+    }
+
   struct type_resolver resolver;
-  type_resolver_init(&resolver, self);
+  type_resolver_init(&resolver, itr);
 
   for (size_t i=0; i < args->children.size; i++)
     {
@@ -119,6 +132,7 @@ struct sym* sym_table_fetch_fun(struct sym_table* self,
       type_init(arg_type, TYPE_VOID);
 
       type_resolver_resolve(&resolver, child, arg_type);
+
       vec_push(&args_ty, arg_type);
     }
 
@@ -177,7 +191,7 @@ struct sym* sym_table_fetch_fun(struct sym_table* self,
 
   if (self->prev)
     {
-      return sym_table_fetch(self->prev, name, NULL);
+      return sym_table_fetch_fun(self->prev, name, args);
     }
 
   return NULL;
@@ -205,7 +219,7 @@ int sym_table_declare(struct sym_table* self,
   assert(self);
   assert(strcmp(name, "") != 0);
 
-  struct sym* s = sym_table_fetch(self, name, NULL);
+  struct sym* s = sym_table_fetch(self, name, new_type);
 
   if (s && s->parent == self->root
       && type_equals(s->type, new_type))
@@ -236,7 +250,7 @@ int sym_table_declare_global(struct sym_table* self,
   assert(self);
   assert(strcmp(name, "") != 0);
 
-  struct sym* s = sym_table_fetch(self, name, NULL);
+  struct sym* s = sym_table_fetch(self, name, new_type);
 
   if (s && s->parent == self->root && s->is_global
       && type_equals(s->type, new_type))
diff --git a/lang/src/sym_table.h b/lang/src/sym_table.h
index 7905f4b..74df115 100644
--- a/lang/src/sym_table.h
+++ b/lang/src/sym_table.h
@@ -20,6 +20,7 @@ struct table {
 };
 
 struct sym_table {
+  struct sym_table* next;
   struct sym_table* prev;
   struct table* root;
   int addr_counter;
diff --git a/lang/src/type_checker.c b/lang/src/type_checker.c
index 4e6b40b..8a66b60 100644
--- a/lang/src/type_checker.c
+++ b/lang/src/type_checker.c
@@ -83,8 +83,8 @@ int type_checker_check(struct type_checker* self,
       struct node* args = node->children.data[1];
 
       struct sym* entry = sym_table_fetch_fun(&self->sym_table,
-                                          target->value,
-                                          args);
+                                              target->value,
+                                              args);
 
       if (!entry)
         {
@@ -109,6 +109,7 @@ int type_checker_check(struct type_checker* self,
         {
           struct type* sub = ty->subtypes.data[i + 1];
           struct node* sub_node = args->children.data[i];
+
           struct type t;
           type_init(&t, TYPE_VOID);
 
@@ -118,6 +119,14 @@ int type_checker_check(struct type_checker* self,
               return 1;
             }
 
+          if (type_checker_check(self, sub_node) != 0)
+            {
+              self->error_line = sub_node->line;
+
+              type_free(&t);
+              return 1;
+            }
+
           if (!type_equals(&t, sub))
             {
               type_checker_error_msg(self, sub_node, sub, &t);
diff --git a/lang/src/type_resolver.c b/lang/src/type_resolver.c
index 299b5fa..5c08062 100644
--- a/lang/src/type_resolver.c
+++ b/lang/src/type_resolver.c
@@ -1,5 +1,6 @@
 #include "type_resolver.h"
 #include "node.h"
+#include "sym_table.h"
 #include "type.h"
 
 void type_resolver_init(struct type_resolver* self,
@@ -40,9 +41,22 @@ int type_resolver_resolve(struct type_resolver* self,
     };
 
     case NODE_CALL: {
+      struct node* target = node->children.data[0];
+      struct node* args = node->children.data[1];
+      struct sym* entry = sym_table_fetch_fun(self->sym_table,
+                                              target->value,
+                                              args);
+
+      if (entry)
+        {
+          type_copy(entry->type->subtypes.data[0], type);
+          return 0;
+        }
+
       struct type call_type;
       type_init(&call_type, TYPE_VOID);
 
+
       if (type_resolver_resolve(self, node->children.data[0], &call_type) == 0
           && call_type.subtypes.size > 0)
         {