Fix crash in program viewer when trying to display new value type

.chronus/changes/fix-playground-program-viewer-crash-2024-5-14-15-45-7.md

@@ -0,0 +1,8 @@
+---
+# Change versionKind to one of: internal, fix, dependencies, feature, deprecation, breaking
+changeKind: feature
+packages:
+  - "@typespec/playground"
+---
+
+Add error recovery for viewer that crash

.chronus/changes/fix-playground-program-viewer-crash-2024-5-14-16-11-12.md

@@ -0,0 +1,8 @@
+---
+# Change versionKind to one of: internal, fix, dependencies, feature, deprecation, breaking
+changeKind: fix
+packages:
+  - "@typespec/html-program-viewer"
+---
+
+Fix crash in program viewer when trying to display new value type

packages/html-program-viewer/src/ui.tsx

@@ -1,5 +1,6 @@
 import { css } from "@emotion/react";
 import {
+  Entity,
   Enum,
   EnumMember,
   getNamespaceFullName,
@@ -132,12 +133,12 @@ const NamedTypeUI = <T extends NamedType>({ type, name, properties }: NamedTypeU
         return undefined;
       }
 
-      const render = (x: any) =>
-        action === "ref" ? <TypeReference type={value} /> : <TypeUI type={x} />;
+      const render = (x: Entity) =>
+        action === "ref" ? <TypeReference type={value} /> : <EntityUI entity={x} />;
       let valueUI;
       if (value === undefined) {
         valueUI = value;
-      } else if (value.kind) {
+      } else if (value.entityKind) {
         valueUI = render(value);
       } else if (
         typeof value === "object" &&
@@ -160,10 +161,19 @@ const NamedTypeUI = <T extends NamedType>({ type, name, properties }: NamedTypeU
 };
 
 interface TypeUIProps {
-  type: Type;
+  readonly entity: Entity;
 }
 
-const TypeUI: FunctionComponent<TypeUIProps> = ({ type }) => {
+const EntityUI: FunctionComponent<TypeUIProps> = ({ entity }) => {
+  switch (entity.entityKind) {
+    case "Type":
+      return <TypeUI type={entity} />;
+    default:
+      return null;
+  }
+};
+
+const TypeUI: FunctionComponent<{ type: Type }> = ({ type }) => {
   switch (type.kind) {
     case "Namespace":
       return <NamespaceUI type={type} />;
@@ -379,7 +389,7 @@ const TypeReference: FunctionComponent<{ type: Type }> = ({ type }) => {
       if (type.name === "") {
         return (
           <KeyValueSection>
-            <TypeUI type={type} />
+            <EntityUI entity={type} />
           </KeyValueSection>
         );
       } else {

packages/playground/package.json

@@ -85,6 +85,7 @@
     "monaco-editor": "~0.46.0",
     "react": "~18.3.1",
     "react-dom": "~18.3.1",
+    "react-error-boundary": "^4.0.13",
     "swagger-ui-dist": "^5.17.10",
     "vscode-languageserver": "~9.0.1",
     "vscode-languageserver-textdocument": "~1.0.11"

packages/playground/src/react/output-view/output-view.module.css

@@ -26,3 +26,7 @@
 .viewer-tabs-container {
   background-color: var(--colorNeutralBackground3);
 }
+
+.viewer-error {
+  padding: 20px;
+}

packages/playground/src/react/output-view/output-view.tsx

@@ -1,5 +1,6 @@
-import { Tab, TabList, type SelectTabEventHandler } from "@fluentui/react-components";
+import { Button, Tab, TabList, type SelectTabEventHandler } from "@fluentui/react-components";
 import { useCallback, useMemo, useState, type FunctionComponent } from "react";
+import { ErrorBoundary, type FallbackProps } from "react-error-boundary";
 import type { PlaygroundEditorsOptions } from "../playground.js";
 import type { CompilationState, CompileResult, FileOutputViewer, ProgramViewer } from "../types.js";
 import { createFileViewer } from "./file-viewer.js";
@@ -81,10 +82,12 @@ const OutputViewInternal: FunctionComponent<{
   return (
     <div className={style["output-view"]}>
       <div className={style["output-content"]}>
-        <viewer.render
-          program={compilationResult.program}
-          outputFiles={compilationResult.outputFiles}
-        />
+        <ErrorBoundary fallbackRender={fallbackRender}>
+          <viewer.render
+            program={compilationResult.program}
+            outputFiles={compilationResult.outputFiles}
+          />
+        </ErrorBoundary>
       </div>
       <div className={style["viewer-tabs-container"]}>
         <TabList
@@ -106,3 +109,13 @@ const OutputViewInternal: FunctionComponent<{
     </div>
   );
 };
+
+function fallbackRender({ error, resetErrorBoundary }: FallbackProps) {
+  return (
+    <div role="alert" className={style["viewer-error"]}>
+      <h2>Something went wrong:</h2>
+      <div style={{ color: "red" }}>{error.toString()}</div>
+      <Button onClick={resetErrorBoundary}>Try again</Button>
+    </div>
+  );
+}