Highlight line that has error

package.json

@@ -25,7 +25,7 @@
     "react-simple-code-editor": "^0.11.0",
     "styled-components": "^5.2.0",
     "typescript": "~3.7.2",
-    "zwiftout": "^0.5.0"
+    "zwiftout": "^1.0.0"
   },
   "scripts": {
     "predeploy": "yarn build",

src/App.tsx

@@ -1,7 +1,7 @@
 import React, { useState, useCallback } from "react";
 import { WorkoutPlot } from "./components/WorkoutPlot";
 import { WorkoutStats } from "./components/WorkoutStats";
-import { parse } from "zwiftout";
+import { parse, ParseError, ValidationError, ZwiftoutException } from "zwiftout";
 import { ErrorMessage } from "./components/ErrorMessage";
 import styled from "styled-components";
 import { CodeEditor } from "./components/CodeEditor";
@@ -32,7 +32,7 @@ const AppContainer = styled.div`
 export function App() {
   const [text, setText] = useState(defaultWorkout);
   const [workout, setWorkout] = useState(parse(defaultWorkout));
-  const [error, setError] = useState<string | undefined>(undefined);
+  const [error, setError] = useState<ZwiftoutException | undefined>(undefined);
 
   const onChange = useCallback(
     (value: string) => {
@@ -41,7 +41,11 @@ export function App() {
         setWorkout(parse(value));
         setError(undefined);
       } catch (e) {
-        setError(e.message);
+        if (e instanceof ParseError || e instanceof ValidationError) {
+          setError(e);
+        } else {
+          throw e;
+        }
       }
     },
     [setText, setWorkout, setError],
@@ -50,9 +54,9 @@ export function App() {
   return (
     <AppContainer>
       <AppTitle />
-      <CodeEditor onValueChange={onChange} value={text} />
+      <CodeEditor onValueChange={onChange} value={text} error={error} />
       <WorkoutPlot intervals={workout.intervals} />
-      {error && <ErrorMessage>{error}</ErrorMessage>}
+      {error && <ErrorMessage>{error.message}</ErrorMessage>}
       <WorkoutStats workout={workout} />
       <ZwoOutput workout={workout} />
       <Credits />

src/components/CodeEditor.tsx

@@ -1,5 +1,7 @@
+import React, { useCallback } from "react";
 import Editor from "react-simple-code-editor";
 import styled from "styled-components";
+import { ZwiftoutException } from "zwiftout";
 
 const highlight = (code: string): string => {
   return code
@@ -11,7 +13,7 @@ const highlight = (code: string): string => {
     .replace(/@(.*?)$/gm, "<code class='comment-start'>@</code><code class='comment'>$1</code>");
 };
 
-export const CodeEditor = styled(Editor).attrs({ padding: 10, highlight })`
+export const BaseCodeEditor = styled(Editor).attrs({ padding: 10 })`
   font-family: source-code-pro, Menlo, Monaco, Consolas, "Courier New", monospace;
   font-size: 14px;
   line-height: 1.3;
@@ -46,4 +48,26 @@ export const CodeEditor = styled(Editor).attrs({ padding: 10, highlight })`
     font-style: italic;
     color: #888;
   }
+  code.error {
+    background-color: rgba(252, 152, 152, 0.5);
+    border-radius: 4px;
+  }
 `;
+
+const highlightErrorLine = (code: string, linenr: number): string => {
+  const regex = new RegExp(`^((?:[^\\n]*?\\n){${linenr}})([^\\n]*?)\\n`);
+  return code.replace(regex, "$1<code class='error'>$2</code>\n");
+};
+
+interface CodeEditorProps {
+  value: string;
+  onValueChange: (value: string) => void;
+  error: ZwiftoutException | undefined;
+}
+
+export const CodeEditor: React.FC<CodeEditorProps> = ({ value, onValueChange, error }) => {
+  const highlightFn = useCallback((code: string) => highlight(error ? highlightErrorLine(code, error.loc.row) : code), [
+    error,
+  ]);
+  return <BaseCodeEditor value={value} onValueChange={onValueChange} highlight={highlightFn} />;
+};

yarn.lock

@@ -11075,10 +11075,10 @@ yargs@^13.3.0, yargs@^13.3.2:
     y18n "^4.0.0"
     yargs-parser "^13.1.2"
 
-zwiftout@^0.5.0:
-  version "0.5.0"
-  resolved "https://registry.yarnpkg.com/zwiftout/-/zwiftout-0.5.0.tgz#ca46fa1e0f16fba185bce97ba8f1d3674011ceff"
-  integrity sha512-GHHd8N27l5AfYs36tl8a5n4sMos8kw7zI5ojA6K3tbyrLRyPAk2EF439CubK0XX5ad0JLr9gnpZwzKrNo5Kd2A==
+zwiftout@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/zwiftout/-/zwiftout-1.0.0.tgz#58dd2f2cf556e97a8a0b7385a2429f4cb2f5fabf"
+  integrity sha512-N1IOERpuInNUwTn8vL97lH/Tuwy8wjTE2XhUybBplmmK9AcPSgSx2Ll4fQXnGHEtEG0Sen5ev9Kv3lgQrdmReQ==
   dependencies:
     argparse "^2.0.1"
     ramda "^0.27.1"