Add JavaScript runtime with eval-based execution and interrupt via worker termination

app/terminal/editor.tsx

@@ -12,6 +12,7 @@ const AceEditor = dynamic(
     await import("ace-builds/src-min-noconflict/ext-searchbox");
     await import("ace-builds/src-min-noconflict/mode-python");
     await import("ace-builds/src-min-noconflict/mode-c_cpp");
+    await import("ace-builds/src-min-noconflict/mode-javascript");
     await import("ace-builds/src-min-noconflict/mode-json");
     await import("ace-builds/src-min-noconflict/mode-csv");
     await import("ace-builds/src-min-noconflict/mode-text");
@@ -28,7 +29,7 @@ import { langConstants } from "./runtime";
 // snippetを有効化するにはsnippetもimportする必要がある: import "ace-builds/src-min-noconflict/snippets/python";
 
 // mode-xxxx.js のファイル名と、AceEditorの mode プロパティの値が対応する
-export type AceLang = "python" | "c_cpp" | "json" | "csv" | "text";
+export type AceLang = "python" | "c_cpp" | "javascript" | "json" | "csv" | "text";
 export function getAceLang(lang: string | undefined): AceLang {
   // Markdownで指定される可能性のある言語名からAceLangを取得
   switch (lang) {
@@ -38,6 +39,9 @@ export function getAceLang(lang: string | undefined): AceLang {
     case "cpp":
     case "c++":
       return "c_cpp";
+    case "javascript":
+    case "js":
+      return "javascript";
     case "json":
       return "json";
     case "csv":

app/terminal/highlight.ts

@@ -3,13 +3,16 @@ import chalk from "chalk";
 import { RuntimeLang } from "./runtime";
 // Python言語定義をインポート
 import "prismjs/components/prism-python";
+import "prismjs/components/prism-javascript";
 
-type PrismLang = "python";
+type PrismLang = "python" | "javascript";
 
 function getPrismLanguage(language: RuntimeLang): PrismLang {
   switch (language) {
     case "python":
       return "python";
+    case "javascript":
+      return "javascript";
     case "cpp":
       throw new Error(
         `highlight for ${language} is disabled because it should not support REPL`

app/terminal/javascript/page.tsx

@@ -0,0 +1,21 @@
+"use client";
+
+import { EditorComponent } from "../editor";
+import { ReplTerminal } from "../repl";
+
+export default function JavaScriptPage() {
+  return (
+    <div className="p-4 flex flex-col gap-4">
+      <ReplTerminal
+        terminalId=""
+        language="javascript"
+        initContent={"> console.log('hello, world!')\nhello, world!"}
+      />
+      <EditorComponent
+        language="javascript"
+        filename="main.js"
+        initContent="console.log('hello, world!');"
+      />
+    </div>
+  );
+}

app/terminal/javascript/runtime.tsx

@@ -0,0 +1,238 @@
+"use client";
+
+import {
+  useState,
+  useRef,
+  useCallback,
+  ReactNode,
+  createContext,
+  useContext,
+  useEffect,
+} from "react";
+import { SyntaxStatus, ReplOutput, ReplCommand } from "../repl";
+import { Mutex, MutexInterface } from "async-mutex";
+import { RuntimeContext } from "../runtime";
+
+const JavaScriptContext = createContext<RuntimeContext>(null!);
+
+export function useJavaScript(): RuntimeContext {
+  const context = useContext(JavaScriptContext);
+  if (!context) {
+    throw new Error("useJavaScript must be used within a JavaScriptProvider");
+  }
+  return context;
+}
+
+type MessageToWorker =
+  | {
+      type: "init";
+      payload?: undefined;
+    }
+  | {
+      type: "runJavaScript";
+      payload: { code: string };
+    }
+  | {
+      type: "checkSyntax";
+      payload: { code: string };
+    }
+  | {
+      type: "restoreState";
+      payload: { commands: string[] };
+    };
+
+type MessageFromWorker =
+  | { id: number; payload: unknown }
+  | { id: number; error: string };
+
+type InitPayloadFromWorker = { success: boolean };
+type RunPayloadFromWorker = {
+  output: ReplOutput[];
+  updatedFiles: [string, string][];
+};
+type StatusPayloadFromWorker = { status: SyntaxStatus };
+
+export function JavaScriptProvider({ children }: { children: ReactNode }) {
+  const workerRef = useRef<Worker | null>(null);
+  const [ready, setReady] = useState<boolean>(false);
+  const mutex = useRef<MutexInterface>(new Mutex());
+  const messageCallbacks = useRef<
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    Map<number, [(payload: any) => void, (error: string) => void]>
+  >(new Map());
+  const nextMessageId = useRef<number>(0);
+  const executedCommands = useRef<string[]>([]);
+
+  function postMessage<T>({ type, payload }: MessageToWorker) {
+    const id = nextMessageId.current++;
+    return new Promise<T>((resolve, reject) => {
+      messageCallbacks.current.set(id, [resolve, reject]);
+      workerRef.current?.postMessage({ id, type, payload });
+    });
+  }
+
+  const initializeWorker = useCallback(() => {
+    const worker = new Worker("/javascript.worker.js");
+    workerRef.current = worker;
+
+    worker.onmessage = (event) => {
+      const data = event.data as MessageFromWorker;
+      if (messageCallbacks.current.has(data.id)) {
+        const [resolve, reject] = messageCallbacks.current.get(data.id)!;
+        if ("error" in data) {
+          reject(data.error);
+        } else {
+          resolve(data.payload);
+        }
+        messageCallbacks.current.delete(data.id);
+      }
+    };
+
+    return postMessage<InitPayloadFromWorker>({
+      type: "init",
+    }).then(({ success }) => {
+      if (success) {
+        setReady(true);
+      }
+      return worker;
+    });
+  }, []);
+
+  useEffect(() => {
+    let worker: Worker | null = null;
+    initializeWorker().then((w) => {
+      worker = w;
+    });
+
+    return () => {
+      worker?.terminate();
+    };
+  }, [initializeWorker]);
+
+  const interrupt = useCallback(() => {
+    // Since we can't interrupt JavaScript execution directly,
+    // we terminate the worker and restart it, then restore state
+
+    // Reject all pending callbacks before terminating
+    const error = "Worker interrupted";
+    messageCallbacks.current.forEach(([, reject]) => reject(error));
+    messageCallbacks.current.clear();
+
+    // Terminate the current worker
+    workerRef.current?.terminate();
+
+    // Reset ready state
+    setReady(false);
+
+    mutex.current.runExclusive(async () => {
+      // Create a new worker and wait for it to be ready
+      await initializeWorker();
+
+      // Restore state by re-executing previous commands
+      if (executedCommands.current.length > 0) {
+        await postMessage<{ success: boolean }>({
+          type: "restoreState",
+          payload: { commands: executedCommands.current },
+        });
+      }
+    });
+  }, [initializeWorker]);
+
+  const runCommand = useCallback(
+    async (code: string): Promise<ReplOutput[]> => {
+      if (!mutex.current.isLocked()) {
+        throw new Error(
+          "mutex of JavaScriptContext must be locked for runCommand"
+        );
+      }
+      if (!workerRef.current || !ready) {
+        return [{ type: "error", message: "JavaScript runtime is not ready yet." }];
+      }
+
+      try {
+        const { output } = await postMessage<RunPayloadFromWorker>({
+          type: "runJavaScript",
+          payload: { code },
+        });
+        // Save successfully executed command
+        executedCommands.current.push(code);
+        return output;
+      } catch (error) {
+        // Handle errors (including "Worker interrupted")
+        if (error instanceof Error) {
+          return [{ type: "error", message: error.message }];
+        }
+        return [{ type: "error", message: String(error) }];
+      }
+    },
+    [ready]
+  );
+
+  const checkSyntax = useCallback(
+    async (code: string): Promise<SyntaxStatus> => {
+      if (!workerRef.current || !ready) return "invalid";
+      const { status } = await mutex.current.runExclusive(() =>
+        postMessage<StatusPayloadFromWorker>({
+          type: "checkSyntax",
+          payload: { code },
+        })
+      );
+      return status;
+    },
+    [ready]
+  );
+
+  const runFiles = useCallback(
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    async (_filenames: string[]): Promise<ReplOutput[]> => {
+      return [
+        {
+          type: "error",
+          message: "JavaScript file execution is not supported in this runtime",
+        },
+      ];
+    },
+    []
+  );
+
+  const splitReplExamples = useCallback((content: string): ReplCommand[] => {
+    const initCommands: { command: string; output: ReplOutput[] }[] = [];
+    for (const line of content.split("\n")) {
+      if (line.startsWith("> ")) {
+        // Remove the prompt from the command
+        initCommands.push({ command: line.slice(2), output: [] });
+      } else {
+        // Lines without prompt are output from the previous command
+        if (initCommands.length > 0) {
+          initCommands[initCommands.length - 1].output.push({
+            type: "stdout",
+            message: line,
+          });
+        }
+      }
+    }
+    return initCommands;
+  }, []);
+
+  const getCommandlineStr = useCallback(
+    (filenames: string[]) => `node ${filenames[0]}`,
+    []
+  );
+
+  return (
+    <JavaScriptContext.Provider
+      value={{
+        ready,
+        runCommand,
+        checkSyntax,
+        mutex: mutex.current,
+        runFiles,
+        interrupt,
+        splitReplExamples,
+        getCommandlineStr,
+      }}
+    >
+      {children}
+    </JavaScriptContext.Provider>
+  );
+}

app/terminal/runtime.tsx

@@ -2,6 +2,7 @@ import { MutexInterface } from "async-mutex";
 import { ReplOutput, SyntaxStatus, ReplCommand } from "./repl";
 import { PyodideProvider, usePyodide } from "./python/runtime";
 import { useWandbox, WandboxProvider } from "./wandbox/runtime";
+import { JavaScriptProvider, useJavaScript } from "./javascript/runtime";
 import { AceLang } from "./editor";
 import { ReactNode } from "react";
 
@@ -28,7 +29,7 @@ export interface LangConstants {
   prompt?: string;
   promptMore?: string;
 }
-export type RuntimeLang = "python" | "cpp";
+export type RuntimeLang = "python" | "cpp" | "javascript";
 
 export function getRuntimeLang(
   lang: string | undefined
@@ -41,6 +42,9 @@ export function getRuntimeLang(
     case "cpp":
     case "c++":
       return "cpp";
+    case "javascript":
+    case "js":
+      return "javascript";
     default:
       console.warn(`Unsupported language for runtime: ${lang}`);
       return undefined;
@@ -50,12 +54,15 @@ export function useRuntime(language: RuntimeLang): RuntimeContext {
   // すべての言語のcontextをインスタンス化
   const pyodide = usePyodide();
   const wandboxCpp = useWandbox("cpp");
+  const javascript = useJavaScript();
 
   switch (language) {
     case "python":
       return pyodide;
     case "cpp":
       return wandboxCpp;
+    case "javascript":
+      return javascript;
     default:
       language satisfies never;
       throw new Error(`Runtime not implemented for language: ${language}`);
@@ -64,7 +71,9 @@ export function useRuntime(language: RuntimeLang): RuntimeContext {
 export function RuntimeProvider({ children }: { children: ReactNode }) {
   return (
     <PyodideProvider>
-      <WandboxProvider>{children}</WandboxProvider>
+      <WandboxProvider>
+        <JavaScriptProvider>{children}</JavaScriptProvider>
+      </WandboxProvider>
     </PyodideProvider>
   );
 }
@@ -77,6 +86,11 @@ export function langConstants(lang: RuntimeLang | AceLang): LangConstants {
         prompt: ">>> ",
         promptMore: "... ",
       };
+    case "javascript":
+      return {
+        tabSize: 2,
+        prompt: "> ",
+      };
     case "c_cpp":
     case "cpp":
       return {