repl: don't use deprecated domain module

Author: avivkeller

doc/api/errors.md

@@ -2016,13 +2016,6 @@ An invalid `options.protocol` was passed to `http.request()`.
 Both `breakEvalOnSigint` and `eval` options were set in the [`REPL`][] config,
 which is not supported.
 
-<a id="ERR_INVALID_REPL_INPUT"></a>
-
-### `ERR_INVALID_REPL_INPUT`
-
-The input may not be used in the [`REPL`][]. The conditions under which this
-error is used are described in the [`REPL`][] documentation.
-
 <a id="ERR_INVALID_RETURN_PROPERTY"></a>
 
 ### `ERR_INVALID_RETURN_PROPERTY`
@@ -3538,6 +3531,13 @@ removed: v16.7.0
 While using the Performance Timing API (`perf_hooks`), a performance mark is
 invalid.
 
+<a id="ERR_INVALID_REPL_INPUT"></a>
+
+### `ERR_INVALID_REPL_INPUT`
+
+The input may not be used in the [`REPL`][]. The conditions under which this
+error is used are described in the [`REPL`][] documentation.
+
 <a id="ERR_INVALID_TRANSFER_OBJECT"></a>
 
 ### `ERR_INVALID_TRANSFER_OBJECT`

doc/api/repl.md

@@ -147,39 +147,6 @@ global or scoped variable, the input `fs` will be evaluated on-demand as
 > fs.createReadStream('./some/file');
 ```
 
-#### Global uncaught exceptions
-
-<!-- YAML
-changes:
-  - version: v12.3.0
-    pr-url: https://github.com/nodejs/node/pull/27151
-    description: The `'uncaughtException'` event is from now on triggered if the
-                 repl is used as standalone program.
--->
-
-The REPL uses the [`domain`][] module to catch all uncaught exceptions for that
-REPL session.
-
-This use of the [`domain`][] module in the REPL has these side effects:
-
-* Uncaught exceptions only emit the [`'uncaughtException'`][] event in the
-  standalone REPL. Adding a listener for this event in a REPL within
-  another Node.js program results in [`ERR_INVALID_REPL_INPUT`][].
-
-  ```js
-  const r = repl.start();
-
-  r.write('process.on("uncaughtException", () => console.log("Foobar"));\n');
-  // Output stream includes:
-  //   TypeError [ERR_INVALID_REPL_INPUT]: Listeners for `uncaughtException`
-  //   cannot be used in the REPL
-
-  r.close();
-  ```
-
-* Trying to use [`process.setUncaughtExceptionCaptureCallback()`][] throws
-  an [`ERR_DOMAIN_CANNOT_SET_UNCAUGHT_EXCEPTION_CAPTURE`][] error.
-
 #### Assignment of the `_` (underscore) variable
 
 <!-- YAML
@@ -768,13 +735,8 @@ avoiding open network interfaces.
 
 [TTY keybindings]: readline.md#tty-keybindings
 [ZSH]: https://en.wikipedia.org/wiki/Z_shell
-[`'uncaughtException'`]: process.md#event-uncaughtexception
 [`--no-experimental-repl-await`]: cli.md#--no-experimental-repl-await
-[`ERR_DOMAIN_CANNOT_SET_UNCAUGHT_EXCEPTION_CAPTURE`]: errors.md#err_domain_cannot_set_uncaught_exception_capture
-[`ERR_INVALID_REPL_INPUT`]: errors.md#err_invalid_repl_input
 [`curl(1)`]: https://curl.haxx.se/docs/manpage.html
-[`domain`]: domain.md
-[`process.setUncaughtExceptionCaptureCallback()`]: process.md#processsetuncaughtexceptioncapturecallbackfn
 [`readline.InterfaceCompleter`]: readline.md#use-of-the-completer-function
 [`repl.ReplServer`]: #class-replserver
 [`repl.start()`]: #replstartoptions

lib/internal/errors.js

@@ -1502,7 +1502,6 @@ E('ERR_INVALID_PROTOCOL',
   TypeError);
 E('ERR_INVALID_REPL_EVAL_CONFIG',
   'Cannot specify both "breakEvalOnSigint" and "eval" for REPL', TypeError);
-E('ERR_INVALID_REPL_INPUT', '%s', TypeError);
 E('ERR_INVALID_RETURN_PROPERTY', (input, name, prop, value) => {
   return `Expected a valid ${input} to be returned for the "${prop}" from the` +
          ` "${name}" hook but got ${determineSpecificType(value)}.`;

lib/repl.js

@@ -60,6 +60,7 @@ const {
   ArrayPrototypeUnshift,
   Boolean,
   Error: MainContextError,
+  FunctionPrototypeApply,
   FunctionPrototypeBind,
   JSONStringify,
   MathMaxApply,
@@ -76,9 +77,9 @@ const {
   ReflectApply,
   RegExp,
   RegExpPrototypeExec,
+  SafeMap,
   SafePromiseRace,
   SafeSet,
-  SafeWeakSet,
   StringPrototypeCharAt,
   StringPrototypeCodePointAt,
   StringPrototypeEndsWith,
@@ -138,7 +139,6 @@ ArrayPrototypeForEach(
   BuiltinModule.getSchemeOnlyModuleNames(),
   (lib) => ArrayPrototypePush(nodeSchemeBuiltinLibs, `node:${lib}`),
 );
-const domain = require('domain');
 let debug = require('internal/util/debuglog').debuglog('repl', (fn) => {
   debug = fn;
 });
@@ -147,7 +147,6 @@ const {
   codes: {
     ERR_CANNOT_WATCH_SIGINT,
     ERR_INVALID_REPL_EVAL_CONFIG,
-    ERR_INVALID_REPL_INPUT,
     ERR_MISSING_ARGS,
     ERR_SCRIPT_EXECUTION_INTERRUPTED,
   },
@@ -191,6 +190,7 @@ const {
 const {
   makeContextifyScript,
 } = require('internal/vm');
+const { createHook } = require('async_hooks');
 let nextREPLResourceNumber = 1;
 // This prevents v8 code cache from getting confused and using a different
 // cache from a resource of the same name
@@ -205,13 +205,43 @@ const globalBuiltins =
   new SafeSet(vm.runInNewContext('Object.getOwnPropertyNames(globalThis)'));
 
 const parentModule = module;
-const domainSet = new SafeWeakSet();
 
 const kBufferedCommandSymbol = Symbol('bufferedCommand');
 const kContextId = Symbol('contextId');
 const kLoadingSymbol = Symbol('loading');
+const kListeningREPLs = new SafeSet();
+const kAsyncREPLMap = new SafeMap();
+let kActiveREPL;
+const kAsyncHook = createHook({
+  init(asyncId) {
+    if (kActiveREPL) {
+      kAsyncREPLMap.set(asyncId, kActiveREPL);
+    }
+  },
+
+  before(asyncId) {
+    kActiveREPL = kAsyncREPLMap.get(asyncId) || kActiveREPL;
+  },
+
+  destroy(asyncId) {
+    kAsyncREPLMap.delete(asyncId);
+  },
+});
+
+let kHasSetUncaughtListener = false;
 
-let addedNewListener = false;
+function handleUncaughtException(er) {
+  kActiveREPL?._onEvalError(er);
+}
+
+function removeListeningREPL(repl) {
+  kListeningREPLs.delete(repl);
+  if (kListeningREPLs.size === 0) {
+    kAsyncHook.disable();
+    kHasSetUncaughtListener = false;
+    process.off('uncaughtException', handleUncaughtException);
+  }
+}
 
 try {
   // Hack for require.resolve("./relative") to work properly.
@@ -346,7 +376,6 @@ function REPLServer(prompt,
 
   this.allowBlockingCompletions = !!options.allowBlockingCompletions;
   this.useColors = !!options.useColors;
-  this._domain = options.domain || domain.create();
   this.useGlobal = !!useGlobal;
   this.ignoreUndefined = !!ignoreUndefined;
   this.replMode = replMode || module.exports.REPL_MODE_SLOPPY;
@@ -369,28 +398,8 @@ function REPLServer(prompt,
     // It is possible to introspect the running REPL accessing this variable
     // from inside the REPL. This is useful for anyone working on the REPL.
     module.exports.repl = this;
-  } else if (!addedNewListener) {
-    // Add this listener only once and use a WeakSet that contains the REPLs
-    // domains. Otherwise we'd have to add a single listener to each REPL
-    // instance and that could trigger the `MaxListenersExceededWarning`.
-    process.prependListener('newListener', (event, listener) => {
-      if (event === 'uncaughtException' &&
-          process.domain &&
-          listener.name !== 'domainUncaughtExceptionClear' &&
-          domainSet.has(process.domain)) {
-        // Throw an error so that the event will not be added and the current
-        // domain takes over. That way the user is notified about the error
-        // and the current code evaluation is stopped, just as any other code
-        // that contains an error.
-        throw new ERR_INVALID_REPL_INPUT(
-          'Listeners for `uncaughtException` cannot be used in the REPL');
-      }
-    });
-    addedNewListener = true;
   }
 
-  domainSet.add(this._domain);
-
   const savedRegExMatches = ['', '', '', '', '', '', '', '', '', ''];
   const sep = '\u0000\u0000\u0000';
   const regExMatcher = new RegExp(`^${sep}(.*)${sep}(.*)${sep}(.*)${sep}(.*)` +
@@ -612,13 +621,8 @@ function REPLServer(prompt,
         }
       } catch (e) {
         err = e;
-
-        if (process.domain) {
-          debug('not recoverable, send to domain');
-          process.domain.emit('error', err);
-          process.domain.exit();
-          return;
-        }
+        self._onEvalError(e);
+        return;
       }
 
       if (awaitPromise && !err) {
@@ -644,10 +648,8 @@ function REPLServer(prompt,
             const result = (await promise)?.value;
             finishExecution(null, result);
           } catch (err) {
-            if (err && process.domain) {
-              debug('not recoverable, send to domain');
-              process.domain.emit('error', err);
-              process.domain.exit();
+            if (err) {
+              self._onEvalError(err);
               return;
             }
             finishExecution(err);
@@ -665,10 +667,17 @@ function REPLServer(prompt,
     }
   }
 
-  self.eval = self._domain.bind(eval_);
+  self.eval = function(...args) {
+    try {
+      kActiveREPL = this;
+      FunctionPrototypeApply(eval_, this, args);
+    } catch (e) {
+      self._onEvalError(e);
+    }
+  };
 
-  self._domain.on('error', function debugDomainError(e) {
-    debug('domain error');
+  self._onEvalError = function _onEvalError(e) {
+    debug('eval error');
     let errStack = '';
 
     if (typeof e === 'object' && e !== null) {
@@ -696,11 +705,6 @@ function REPLServer(prompt,
       });
       decorateErrorStack(e);
 
-      if (e.domainThrown) {
-        delete e.domain;
-        delete e.domainThrown;
-      }
-
       if (isError(e)) {
         if (e.stack) {
           if (e.name === 'SyntaxError') {
@@ -740,10 +744,13 @@ function REPLServer(prompt,
       self.lastError = e;
     }
 
-    if (options[kStandaloneREPL] &&
-        process.listenerCount('uncaughtException') !== 0) {
+    if (options[kStandaloneREPL] && process.listenerCount('uncaughtException') > 1) {
       process.nextTick(() => {
-        process.emit('uncaughtException', e);
+        const listeners = process.listeners('uncaughtException');
+        for (let i = 0; i < listeners.length; i++) {
+          const listener = listeners[i];
+          if (listener !== handleUncaughtException) listener(e);
+        }
         self.clearBufferedCommand();
         self.lines.level = [];
         self.displayPrompt();
@@ -778,7 +785,14 @@ function REPLServer(prompt,
       self.lines.level = [];
       self.displayPrompt();
     }
-  });
+  };
+  kListeningREPLs.add(self);
+
+  if (!kHasSetUncaughtListener) {
+    kAsyncHook.enable();
+    process.on('uncaughtException', handleUncaughtException);
+    kHasSetUncaughtListener = true;
+  }
 
   self.clearBufferedCommand();
 
@@ -951,7 +965,7 @@ function REPLServer(prompt,
           self.displayPrompt();
           return;
         }
-        self._domain.emit('error', e.err || e);
+        self._onEvalError(e.err || e);
       }
 
       // Clear buffer if no SyntaxErrors
@@ -971,8 +985,7 @@ function REPLServer(prompt,
         self.output.write(self.writer(ret) + '\n');
       }
 
-      // Display prompt again (unless we already did by emitting the 'error'
-      // event on the domain instance).
+      // Display prompt again
       if (!e) {
         self.displayPrompt();
       }
@@ -1082,15 +1095,17 @@ REPLServer.prototype.clearBufferedCommand = function clearBufferedCommand() {
 REPLServer.prototype.close = function close() {
   if (this.terminal && this._flushing && !this._closingOnFlush) {
     this._closingOnFlush = true;
-    this.once('flushHistory', () =>
-      ReflectApply(Interface.prototype.close, this, []),
-    );
+    this.once('flushHistory', () => {
+      removeListeningREPL(this);
+      ReflectApply(Interface.prototype.close, this, []);
+    });
 
     return;
   }
-  process.nextTick(() =>
-    ReflectApply(Interface.prototype.close, this, []),
-  );
+  process.nextTick(() => {
+    removeListeningREPL(this);
+    ReflectApply(Interface.prototype.close, this, []);
+  });
 };
 
 REPLServer.prototype.createContext = function() {

test/fixtures/repl-tab-completion-nested-repls.js

@@ -32,9 +32,7 @@ const putIn = new ArrayStream();
 const testMe = repl.start('', putIn);
 
 // Some errors are passed to the domain, but do not callback.
-testMe._domain.on('error', function(err) {
-  throw err;
-});
+testMe._onEvalError = (err) => { throw err };
 
 // Nesting of structures causes REPL to use a nested REPL for completion.
 putIn.run([