added parsing and testing for grouped expressions

src/parser/parser.cpp

@@ -46,6 +46,11 @@ namespace parser {
             std::bind(&parser::parse_boolean, this)
         );
 
+        register_prefix(
+            token::type::LPAREN,
+            std::bind(&parser::parse_grouped_expr, this)
+        );
+
         using namespace std::placeholders;
         register_infix(
             {token::type::PLUS,
@@ -238,6 +243,19 @@ namespace parser {
         return ret;
     };
 
+    ast::expression* parser::parse_grouped_expr() {
+        // TRACE_FUNCTION;
+        next_token();
+        ast::expression* ret = parse_expression(precedence::LOWEST);
+
+        if (!expect_next(token::type::RPAREN)) {
+            delete ret;
+            return nullptr;
+        }
+
+        return ret;
+    };
+
     ast::expression* parser::parse_infix_expr(ast::expression* left) {
         // TRACE_FUNCTION;
         ast::infix_expr* ret =

src/parser/parser.hpp

@@ -53,6 +53,7 @@ namespace parser {
         ast::expression* parse_integer();
         ast::expression* parse_boolean();
         ast::expression* parse_prefix_expr();
+        ast::expression* parse_grouped_expr();
 
         ast::expression* parse_infix_expr(ast::expression*);
     };

test/parser/expression.cpp

@@ -236,6 +236,11 @@ TEST_SUITE("Parser: expression") {
              "((3 + (4 * 5)) == ((3 * 1) + (4 * 5)))"},
             {"3 > 5 == false", "((3 > 5) == false)"},
             {"3 < 5 == true", "((3 < 5) == true)"},
+            {"1 + (2 + 3)", "(1 + (2 + 3))"},
+            {"(1 + a) * 17", "((1 + a) * 17)"},
+            {"2 / (5 + 5)", "(2 / (5 + 5))"},
+            {"-(5 + a)", "(-(5 + a))"},
+            {"!(true == true)", "(!(true == true))"},
         };
 
         for (auto& t : tests) {