[PATCH olang v1 3/3] parser: parse function params

[Johnny Richard <johnny@johnnyrichard.com>]

Signed-off-by: Johnny Richard <johnny@johnnyrichard.com>
---
 src/ast.c                              | 19 +++++++-
 src/ast.h                              | 12 ++++-
 src/parser.c                           | 66 ++++++++++++++++++++++----
 src/pretty_print_ast.c                 | 17 +++++++
 tests/olc/0027_function_with_params.ol |  9 ++++
 5 files changed, 112 insertions(+), 11 deletions(-)

diff --git a/src/ast.c b/src/ast.c
index bb74679..dc2e019 100644
--- a/src/ast.c
+++ b/src/ast.c
@@ -40,8 +40,12 @@ ast_new_translation_unit(arena_t *arena)
 }
 
 ast_node_t *
-ast_new_node_fn_def(arena_t *arena, string_view_t id, string_view_t return_type, ast_node_t *block)
+ast_new_node_fn_def(arena_t *arena, string_view_t id, list_t *params, string_view_t return_type, ast_node_t *block)
 {
+    assert(arena);
+    assert(params);
+    assert(block);
+
     ast_node_t *node_fn_def = (ast_node_t *)arena_alloc(arena, sizeof(ast_node_t));
     assert(node_fn_def);
 
@@ -51,6 +55,7 @@ ast_new_node_fn_def(arena_t *arena, string_view_t id, string_view_t return_type,
     fn_def->id = id;
     fn_def->return_type = return_type;
     fn_def->block = block;
+    fn_def->params = params;
 
     return node_fn_def;
 }
@@ -151,3 +156,15 @@ ast_new_node_block(arena_t *arena)
 
     return node_block;
 }
+
+ast_fn_param_t *
+ast_new_fn_param(arena_t *arena, string_view_t id, string_view_t type_id)
+{
+    ast_fn_param_t *fn_param = (ast_fn_param_t *)arena_alloc(arena, sizeof(ast_fn_param_t));
+    assert(fn_param);
+
+    fn_param->id = id;
+    fn_param->type_id = type_id;
+
+    return fn_param;
+}
diff --git a/src/ast.h b/src/ast.h
index 6cfbfc0..7ba431f 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -51,9 +51,16 @@ typedef struct ast_translation_unit
     list_t *decls;
 } ast_translation_unit_t;
 
+typedef struct ast_fn_param
+{
+    string_view_t id;
+    string_view_t type_id;
+} ast_fn_param_t;
+
 typedef struct ast_fn_definition
 {
     string_view_t id;
+    list_t *params;
     string_view_t return_type;
     ast_node_t *block;
     scope_t *scope;
@@ -149,7 +156,7 @@ ast_node_t *
 ast_new_translation_unit(arena_t *arena);
 
 ast_node_t *
-ast_new_node_fn_def(arena_t *arena, string_view_t id, string_view_t return_type, ast_node_t *block);
+ast_new_node_fn_def(arena_t *arena, string_view_t id, list_t *params, string_view_t return_type, ast_node_t *block);
 
 ast_node_t *
 ast_new_node_var_def(arena_t *arena, string_view_t id, string_view_t type, ast_node_t *value);
@@ -172,4 +179,7 @@ ast_new_node_if_stmt(arena_t *arena, ast_node_t *cond, ast_node_t *then, ast_nod
 ast_node_t *
 ast_new_node_block(arena_t *arena);
 
+ast_fn_param_t *
+ast_new_fn_param(arena_t *arena, string_view_t id, string_view_t type_id);
+
 #endif /* AST_H */
diff --git a/src/parser.c b/src/parser.c
index c79f3bd..11bb1cd 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -16,6 +16,7 @@
  */
 
 #include <assert.h>
+#include <errno.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <string.h>
@@ -48,9 +49,12 @@ parser_parse_if_stmt(parser_t *parser);
 static ast_node_t *
 parser_parse_var_def(parser_t *parser);
 
-ast_node_t *
+static ast_node_t *
 parser_parse_fn_definition(parser_t *parser);
 
+static list_t *
+parser_parse_fn_params(parser_t *parser);
+
 static ast_node_t *
 parser_parse_expr(parser_t *parser);
 
@@ -262,6 +266,55 @@ parser_parse_factor(parser_t *parser)
     }
 }
 
+static list_t *
+parser_parse_fn_params(parser_t *parser)
+{
+    if (!skip_expected_token(parser, TOKEN_OPAREN)) {
+        return NULL;
+    }
+
+    list_t *params = arena_alloc(parser->arena, sizeof(list_t));
+    if (params == NULL) {
+        fprintf(stderr, "[FATAL] Out of memory: parser_parse_fn_params: %s\n", strerror(errno));
+        exit(EXIT_FAILURE);
+    }
+
+    list_init(params, parser->arena);
+
+    skip_line_feeds(parser->lexer);
+
+    token_t token;
+    lexer_next_token(parser->lexer, &token);
+
+    bool is_not_first_param = false;
+
+    while (token.kind != TOKEN_CPAREN && token.kind != TOKEN_EOF) {
+        if (is_not_first_param && expected_token(parser, &token, TOKEN_COMMA)) {
+            lexer_next_token(parser->lexer, &token);
+        }
+
+        if (!expected_token(parser, &token, TOKEN_ID)) {
+            return NULL;
+        }
+
+        string_view_t type_id;
+        parser_parse_type(parser, &type_id);
+
+        ast_fn_param_t *param = ast_new_fn_param(parser->arena, token.value, type_id);
+        list_append(params, param);
+
+        skip_line_feeds(parser->lexer);
+        lexer_next_token(parser->lexer, &token);
+        is_not_first_param = true;
+    }
+
+    if (!expected_token(parser, &token, TOKEN_CPAREN)) {
+        return NULL;
+    }
+
+    return params;
+}
+
 ast_node_t *
 parser_parse_fn_definition(parser_t *parser)
 {
@@ -279,13 +332,8 @@ parser_parse_fn_definition(parser_t *parser)
 
     skip_line_feeds(parser->lexer);
 
-    if (!skip_expected_token(parser, TOKEN_OPAREN)) {
-        return NULL;
-    }
-
-    skip_line_feeds(parser->lexer);
-
-    if (!skip_expected_token(parser, TOKEN_CPAREN)) {
+    list_t *params = parser_parse_fn_params(parser);
+    if (params == NULL) {
         return NULL;
     }
 
@@ -301,7 +349,7 @@ parser_parse_fn_definition(parser_t *parser)
         return NULL;
     }
 
-    return ast_new_node_fn_def(parser->arena, fn_name_token.value, fn_return_type, block);
+    return ast_new_node_fn_def(parser->arena, fn_name_token.value, params, fn_return_type, block);
 }
 
 static bool
diff --git a/src/pretty_print_ast.c b/src/pretty_print_ast.c
index 8116e60..b53ea5c 100644
--- a/src/pretty_print_ast.c
+++ b/src/pretty_print_ast.c
@@ -108,6 +108,17 @@ pretty_print_node_new(arena_t *arena)
     return node;
 }
 
+static pretty_print_node_t *
+pretty_print_new_fn_param(ast_fn_param_t *param, arena_t *arena)
+{
+    pretty_print_node_t *node = pretty_print_node_new(arena);
+    char name[256];
+    sprintf(name, "Param_Definition <name:" SV_FMT "> <type:" SV_FMT ">", SV_ARG(param->id), SV_ARG(param->type_id));
+    node->name = (char *)arena_alloc(arena, sizeof(char) * (strlen(name) + 1));
+    strcpy(node->name, name);
+    return node;
+}
+
 static pretty_print_node_t *
 ast_node_to_pretty_print_node(ast_node_t *ast, arena_t *arena)
 {
@@ -141,6 +152,12 @@ ast_node_to_pretty_print_node(ast_node_t *ast, arena_t *arena)
             node->name = (char *)arena_alloc(arena, sizeof(char) * (strlen(name) + 1));
             strcpy(node->name, name);
 
+            list_item_t *param = list_head(fn_def.params);
+            while (param != NULL) {
+                list_append(node->children, pretty_print_new_fn_param(param->value, arena));
+                param = list_next(param);
+            }
+
             pretty_print_node_t *block = ast_node_to_pretty_print_node(fn_def.block, arena);
             list_append(node->children, block);
             return node;
diff --git a/tests/olc/0027_function_with_params.ol b/tests/olc/0027_function_with_params.ol
index f70fe7c..1d74d39 100644
--- a/tests/olc/0027_function_with_params.ol
+++ b/tests/olc/0027_function_with_params.ol
@@ -39,3 +39,12 @@ fn main(argc: u8, argv: u64): u8 {
 # ./0027_function_with_params.ol:18:1: <}>
 # END
 
+# TEST test_ast WITH
+# Translation_Unit
+# `-Function_Definition <name:main> <return:u8>
+#   |-Param_Definition <name:argc> <type:u8>
+#   |-Param_Definition <name:argv> <type:u64>
+#   `-Block
+#     `-Return_Statement
+#       `-Literal <kind:u32> <value:0>
+# END
-- 
2.46.0