parser: Ensure the expression types

When assign a variable or returning a value it now ensures that the
expression matches the expected type.

To make this possible a %result_type% field was added to ast_node_t and
this field is used whenever to make the comparison.

Signed-off-by: Carlos Maniero <carlos@maniero.me>
Signed-off-by: Johnny Richard <johnny@johnnyrichard.com>

1 files changed, 23 insertions, 2 deletions

diff --git a/src/ast.c b/src/ast.c
index 8a46034..4fd5a3f 100644
--- a/src/ast.c
+++ b/src/ast.c
@@ -73,6 +73,7 @@ ast_node_new_return_stmt(ast_node_t *argument)
   ast_node_t *node = ast_node_new();
 
   *node = (ast_node_t){
+    .result_type = TYPE_VOID,
     .kind = AST_RETURN_STMT,
     .data = { .return_stmt = { .argument = argument } },
   };
@@ -106,6 +107,7 @@ ast_node_new_literal_integer(uint32_t number)
 
   *node = (ast_node_t){
     .kind = AST_LITERAL,
+    .result_type = TYPE_I32,
     .data = {
       .literal = {
         .kind = AST_LITERAL_INTEGER,
@@ -124,6 +126,7 @@ ast_node_new_literal_bool(bool boolean)
 
   *node = (ast_node_t){
     .kind = AST_LITERAL,
+    .result_type = TYPE_BOOL,
     .data = {
       .literal = {
         .kind = AST_LITERAL_BOOL,
@@ -136,12 +139,13 @@ ast_node_new_literal_bool(bool boolean)
 }
 
 ast_node_t *
-ast_node_new_binary_operation(ast_binary_operation_kind_t kind, ast_node_t *left, ast_node_t *right)
+ast_node_new_binary_operation(ast_binary_operation_kind_t kind, ast_node_t *left, ast_node_t *right, type_t result_type)
 {
   ast_node_t *node = ast_node_new();
 
   *node = (ast_node_t){
     .kind = AST_BINARY_OPERATION,
+    .result_type = result_type,
     .data = {
       .binary_operation = {
         .kind = kind,
@@ -161,6 +165,7 @@ ast_node_new_variable_declaration(string_view_t variable_name, type_t type, ast_
 
   *node = (ast_node_t){
     .kind = AST_VARIABLE_DECLARATION,
+    .result_type = TYPE_VOID,
     .data = {
       .variable_declaration = {
         .identifier = { .name = variable_name },
@@ -180,6 +185,7 @@ ast_node_new_variable_assignment(ast_identifier_t *identifier, ast_node_t *expre
 
   *node = (ast_node_t){
     .kind = AST_VARIABLE_ASSIGNMENT,
+    .result_type = TYPE_VOID,
     .data = {
       .variable_assignment = {
         .identifier = identifier,
@@ -192,14 +198,29 @@ ast_node_new_variable_assignment(ast_identifier_t *identifier, ast_node_t *expre
 }
 
 ast_node_t *
-ast_node_new_variable(ast_identifier_t *identifier)
+ast_node_new_variable(ast_identifier_t *identifier, type_t result_type)
 {
   ast_node_t *node = ast_node_new();
 
   *node = (ast_node_t){
     .kind = AST_VARIABLE,
+    .result_type = result_type,
     .data = { .variable = { .identifier = identifier } },
   };
 
   return node;
 }
+
+char *
+ast_type_to_str(type_t type)
+{
+  switch (type) {
+    case TYPE_I32:
+      return "i32";
+    case TYPE_BOOL:
+      return "bool";
+    case TYPE_VOID:
+      return "void";
+  }
+  assert(false);
+}