add more unit tests for lexing

tests/test_lex.rs

@@ -45,4 +45,109 @@ mod lex_tests {
             }
         }
     }
+
+    #[test]
+    fn test_bad_symbol() {
+        let document: &str = "(as;dd)";
+        let output: &str = "Problem lexing document: \"Unparsable token:as;dd\"";
+        match lex(document.to_string()) {
+            Ok(box_cell) => {
+                print!("Bad token yielded: {}\n", *box_cell);
+                assert!(false);
+            },
+            Err(s) => {
+                assert_eq!(s, output.to_string());
+            }
+        }
+    }
+
+    #[test]
+    fn test_unmatched_list_delim_flat() {
+        let document: &str = "(one two";
+        let output: &str = "Problem lexing document: \"Unmatched list delimiter in input\"";
+        match lex(document.to_string()) {
+            Ok(box_cell) => {
+                print!("Bad token yielded: {}\n", *box_cell);
+                assert!(false);
+            },
+            Err(s) => {
+                assert_eq!(s, output.to_string());
+            }
+        }
+    }
+
+    #[test]
+    fn test_unmatched_list_delim_complex() {
+        let document: &str = "(one two (three)";
+        let output: &str = "Problem lexing document: \"Unmatched list delimiter in input\"";
+        match lex(document.to_string()) {
+            Ok(box_cell) => {
+                print!("Bad token yielded: {}\n", *box_cell);
+                assert!(false);
+            },
+            Err(s) => {
+                assert_eq!(s, output.to_string());
+            }
+        }
+    }
+
+    #[test]
+    fn test_comment() {
+        let document: &str = "#!/bin/relish\n(one two)";
+        let output: &str = "(one two nil)";
+        match lex(document.to_string()) {
+            Ok(box_cell) => {
+                assert_eq!(format!("{}", *box_cell), output.to_string());
+            },
+            Err(s) => {
+                print!("{}\n", s);
+                assert!(false);
+            }
+        }
+    }
+
+    #[test]
+    fn test_postline_comment() {
+        let document: &str = "#!/bin/relish\n((one two)# another doc comment\n(three four))";
+        let output: &str = "(one two nil)";
+        match lex(document.to_string()) {
+            Ok(box_cell) => {
+                assert_eq!(format!("{}", *box_cell), output.to_string());
+            },
+            Err(s) => {
+                print!("{}\n", s);
+                assert!(false);
+            }
+        }
+    }
+
+    #[test]
+    fn test_inline_comment() {
+        let document: &str = "#!/bin/relish\n((one two)\n# another doc comment\nthree)";
+        let output: &str = "(one two nil)";
+        match lex(document.to_string()) {
+            Ok(box_cell) => {
+                assert_eq!(format!("{}", *box_cell), output.to_string());
+            },
+            Err(s) => {
+                print!("{}\n", s);
+                assert!(false);
+            }
+        }
+    }
+
+    #[test]
+    fn test_bad_token_list() {
+        let document: &str = "(one t(wo)";
+        let output: &str = "Problem lexing document: \"list started in middle of another token\"";
+        match lex(document.to_string()) {
+            Ok(box_cell) => {
+                print!("Bad token yielded: {}\n", *box_cell);
+                assert!(false);
+            },
+            Err(s) => {
+                assert_eq!(s, output.to_string());
+            }
+        }
+    }
 }