added a bit of tests

src/lexer.rs

@@ -73,3 +73,62 @@ impl<'a> Display for Token<'a> {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use Token::*;
+
+    fn assert_lex(src: &str, expected: &[Token]) {
+        assert_eq!(Token::lexer(src).collect::<Vec<_>>(), expected)
+    }
+    #[test]
+    fn gibberish() {
+        assert_lex(
+            "(][)}'{\"ABLE\"corp :wisp ¨",
+            &[
+                LeftParen,
+                RightBracket,
+                LeftBracket,
+                RightParen,
+                RightCurly,
+                Quote,
+                LeftCurly,
+                String("ABLE"),
+                Symbol("corp"),
+                Keyword("wisp"),
+                Error,
+            ],
+        )
+    }
+
+    #[test]
+    fn function() {
+        assert_lex(
+            "(defun print-add [x y] (println (add x y))) (print-add 42 12)",
+            &[
+                LeftParen,
+                Symbol("defun"),
+                Symbol("print-add"),
+                LeftBracket,
+                Symbol("x"),
+                Symbol("y"),
+                RightBracket,
+                LeftParen,
+                Symbol("println"),
+                LeftParen,
+                Symbol("add"),
+                Symbol("x"),
+                Symbol("y"),
+                RightParen,
+                RightParen,
+                RightParen,
+                LeftParen,
+                Symbol("print-add"),
+                Number(42.0.into()),
+                Number(12.0.into()),
+                RightParen,
+            ],
+        )
+    }
+}

src/parser.rs

@@ -61,3 +61,28 @@ fn stream_of_lexer<'a>(
     let len = lexer.source().len();
     Stream::from_iter(len..len + 1, lexer.spanned())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn assert_parse(src: &str, expected: &[Value]) {
+        assert_eq!(read(src).unwrap(), expected)
+    }
+
+    #[test]
+    fn simple_fn() {
+        assert_parse(
+            "(defn test [] (println \"Hello, world!\"))",
+            &[Value::List(Box::new(List::from_vec(vec![
+                Value::Symbol("defn".into()),
+                Value::Symbol("test".into()),
+                Value::Vector(vec![]),
+                Value::List(Box::new(List::from_vec(vec![
+                    Value::Symbol("println".into()),
+                    Value::String("Hello, world!".into()),
+                ]))),
+            ])))],
+        )
+    }
+}