Add test

dust-lang/src/parser/mod.rs

@@ -227,16 +227,7 @@ impl<'src> Parser<'src> {
 
     fn parse_grouped(&mut self, _allow_assignment: bool) -> Result<(), ParseError> {
         self.parse_expression()?;
-
-        if self.previous_token == Token::RightParenthesis {
-            Ok(())
-        } else {
-            Err(ParseError::ExpectedToken {
-                expected: TokenKind::RightParenthesis,
-                found: self.current_token.to_owned(),
-                position: self.current_position,
-            })
-        }
+        self.expect(TokenKind::RightParenthesis)
     }
 
     fn parse_unary(&mut self, _allow_assignment: bool) -> Result<(), ParseError> {

dust-lang/src/parser/tests.rs

@@ -2,6 +2,30 @@ use crate::Local;
 
 use super::*;
 
+#[test]
+fn parentheses_precedence() {
+    assert_eq!(
+        parse("(1 + 2) * 3"),
+        Ok(Chunk::with_data(
+            vec![
+                (
+                    *Instruction::add(0, 0, 1)
+                        .set_first_argument_to_constant()
+                        .set_second_argument_to_constant(),
+                    Span(3, 4)
+                ),
+                (
+                    *Instruction::multiply(1, 0, 2).set_second_argument_to_constant(),
+                    Span(8, 9)
+                ),
+                (Instruction::r#return(), Span(0, 11)),
+            ],
+            vec![Value::integer(1), Value::integer(2), Value::integer(3)],
+            vec![]
+        ))
+    );
+}
+
 #[test]
 fn add_multiply_precedence() {
     assert_eq!(
@@ -42,7 +66,7 @@ fn let_statement() {
 }
 
 #[test]
-fn integer() {
+fn constant() {
     assert_eq!(
         parse("42"),
         Ok(Chunk::with_data(