Nicer error messages for unknown tokens

src/wasm-lib/kcl/src/parser.rs

@@ -36,13 +36,13 @@ impl Parser {
 
         if !self.unknown_tokens.is_empty() {
             let source_ranges = self.unknown_tokens.iter().map(SourceRange::from).collect();
-            return Err(KclError::Lexical(KclErrorDetails {
+            let token_list = self.unknown_tokens.iter().map(|t| t.value.as_str()).collect::<Vec<_>>();
-                source_ranges,
+            let message = if token_list.len() == 1 {
-                message: format!(
+                format!("found unknown token '{}'", token_list[0])
-                    "found unknown tokens {:?}",
+            } else {
-                    self.unknown_tokens.iter().map(|t| t.value.as_str()).collect::<Vec<_>>()
+                format!("found unknown tokens [{}]", token_list.join(", "))
-                ),
+            };
-            }));
+            return Err(KclError::Lexical(KclErrorDetails { source_ranges, message }));
         }
 
         parser_impl::run_parser(&mut self.tokens.as_slice())

src/wasm-lib/kcl/src/parser/parser_impl.rs

@@ -2216,7 +2216,7 @@ const secondExtrude = startSketchOn('XY')
         let err = parser.ast().unwrap_err();
         // TODO: Better errors when program cannot tokenize.
         // https://github.com/KittyCAD/modeling-app/issues/696
-        assert!(err.to_string().contains("found list of unknown tokens"));
+        assert!(err.to_string().contains("found unknown token"));
     }
 
     #[test]
@@ -2276,7 +2276,7 @@ z(-[["#,
         // https://github.com/KittyCAD/modeling-app/issues/696
         assert_eq!(
             result.err().unwrap().to_string(),
-            r##"lexical: KclErrorDetails { source_ranges: [SourceRange([6, 7])], message: "found list of unknown tokens \"#\"" }"##
+            r##"lexical: KclErrorDetails { source_ranges: [SourceRange([6, 7])], message: "found unknown token '#'" }"##
         );
     }
 
@@ -2290,7 +2290,7 @@ z(-[["#,
         // https://github.com/KittyCAD/modeling-app/issues/696
         assert_eq!(
             result.err().unwrap().to_string(),
-            r##"lexical: KclErrorDetails { source_ranges: [SourceRange([25, 26]), SourceRange([26, 27])], message: "found list of unknown tokens \"# #\"" }"##
+            r##"lexical: KclErrorDetails { source_ranges: [SourceRange([25, 26]), SourceRange([26, 27])], message: "found unknown tokens [#, #]" }"##
         );
     }