Merge pull request #5 from froth/parser

Testing based on to_string, wrong but more readable
froth · Jan 11, 2024 · ad64b45 · ad64b45
2 parents b654848 + 59d161a
commit ad64b45
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Showing 3 changed files with 11 additions and 20 deletions.
diff --git a/src/expr.rs b/src/expr.rs
@@ -31,7 +31,7 @@ impl Expr {
 impl Display for Expr {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
-            Self::Binary(left, token, right) => write!(f, "({} {} {})", token.lexeme, left, right),
+            Self::Binary(left, token, right) => write!(f, "({} {} {})", token.token_type, left, right),
             Self::Grouping(expr) => write!(f, "(group {})", expr),
             Self::Literal(literal) => write!(f, "({})", literal),
             Self::Unary(token, right) => write!(f, "({} {})", token.lexeme, right),

diff --git a/src/parser.rs b/src/parser.rs
@@ -128,7 +128,7 @@ mod parser_tests {
         ];
         let mut parser = Parser::new(tokens);
         let expr = parser.parse();
-        assert_matches!(expr, Expr::Literal(Literal::String(s)) if string == s);
+        assert_eq!(expr.to_string(), r#"("foo")"#);
     }
 
     #[test]
@@ -144,24 +144,7 @@ mod parser_tests {
         ];
         let mut parser = Parser::new(tokens);
         let expr = parser.parse();
-        match expr {
-            Expr::Binary(lhs, op, rhs) => {
-                assert_matches!(op.token_type, TokenType::EqualEqual);
-                assert_matches!(
-                    *lhs,
-                    Expr::Binary(
-                        _,
-                        Token {
-                            token_type: TokenType::BangEqual,
-                            ..
-                        },
-                        _
-                    )
-                );
-                assert_matches!(*rhs, Expr::Literal(Literal::String(_)));
-            }
-            _ => panic!("should be binary"),
-        }
+        assert_eq!(expr.to_string(), r#"(EqualEqual (BangEqual ("foo") ("foo")) ("foo"))"#);
     }
 
     fn token(token_type: TokenType) -> Token {

diff --git a/src/token.rs b/src/token.rs
@@ -1,3 +1,5 @@
+use std::fmt::Display;
+
 #[derive(Debug, Clone)]
 pub enum TokenType {
     //single character tokens.
@@ -49,6 +51,12 @@ pub enum TokenType {
     Eof,
 }
 
+impl Display for TokenType {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{:?}", self) // Display in terms of debug. Antipattern?
+    }
+}
+
 #[derive(Debug, Clone)]
 pub struct Token {
     pub token_type: TokenType,