vm: add run-after-evaluate microtask mode

This allows timeouts to apply to e.g. `Promise`s and `async function`s
from code running inside of `vm.Context`s, by giving the Context its
own microtasks queue.

Fixes: https://github.com/nodejs/node/issues/3020

PR-URL: https://github.com/nodejs/node/pull/34023
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Denys Otrishko <shishugi@gmail.com>

doc/api/vm.md

@@ -188,6 +188,9 @@ overhead.
 <!-- YAML
 added: v0.3.1
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/34023
+    description: The `microtaskMode` option is supported now.
   - version: v10.0.0
     pr-url: https://github.com/nodejs/node/pull/19016
     description: The `contextCodeGeneration` option is supported now.
@@ -225,6 +228,10 @@ changes:
       `EvalError`. **Default:** `true`.
     * `wasm` {boolean} If set to false any attempt to compile a WebAssembly
       module will throw a `WebAssembly.CompileError`. **Default:** `true`.
+  * `microtaskMode` {string} If set to `afterEvaluate`, microtasks (tasks
+    scheduled through `Promise`s any `async function`s) will be run immediately
+    after the script has run. They are included in the `timeout` and
+    `breakOnSigint` scopes in that case.
 * Returns: {any} the result of the very last statement executed in the script.
 
 First contextifies the given `contextObject`, runs the compiled code contained
@@ -846,6 +853,9 @@ function with the given `params`.
 <!-- YAML
 added: v0.3.1
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/34023
+    description: The `microtaskMode` option is supported now.
   - version: v10.0.0
     pr-url: https://github.com/nodejs/node/pull/19398
     description: The first argument can no longer be a function.
@@ -871,6 +881,10 @@ changes:
       `EvalError`. **Default:** `true`.
     * `wasm` {boolean} If set to false any attempt to compile a WebAssembly
       module will throw a `WebAssembly.CompileError`. **Default:** `true`.
+  * `microtaskMode` {string} If set to `afterEvaluate`, microtasks (tasks
+    scheduled through `Promise`s any `async function`s) will be run immediately
+    after a script has run through [`script.runInContext()`][].
+    They are included in the `timeout` and `breakOnSigint` scopes in that case.
 * Returns: {Object} contextified object.
 
 If given a `contextObject`, the `vm.createContext()` method will [prepare
@@ -1002,6 +1016,9 @@ console.log(contextObject);
 <!-- YAML
 added: v0.3.1
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/34023
+    description: The `microtaskMode` option is supported now.
   - version: v10.0.0
     pr-url: https://github.com/nodejs/node/pull/19016
     description: The `contextCodeGeneration` option is supported now.
@@ -1068,6 +1085,10 @@ changes:
     * Returns: {Module Namespace Object|vm.Module} Returning a `vm.Module` is
       recommended in order to take advantage of error tracking, and to avoid
       issues with namespaces that contain `then` function exports.
+  * `microtaskMode` {string} If set to `afterEvaluate`, microtasks (tasks
+    scheduled through `Promise`s any `async function`s) will be run immediately
+    after the script has run. They are included in the `timeout` and
+    `breakOnSigint` scopes in that case.
 * Returns: {any} the result of the very last statement executed in the script.
 
 The `vm.runInNewContext()` first contextifies the given `contextObject` (or
@@ -1224,13 +1245,13 @@ within which it can operate. The process of creating the V8 Context and
 associating it with the `contextObject` is what this document refers to as
 "contextifying" the object.
 
-## Timeout limitations when using `process.nextTick()`, promises, and `queueMicrotask()`
+## Timeout interactions with asynchronous tasks and Promises
 
-Because of the internal mechanics of how the `process.nextTick()` queue and
-the microtask queue that underlies Promises are implemented within V8 and
-Node.js, it is possible for code running within a context to "escape" the
-`timeout` set using `vm.runInContext()`, `vm.runInNewContext()`, and
-`vm.runInThisContext()`.
+`Promise`s and `async function`s can schedule tasks run by the JavaScript
+engine asynchronously. By default, these tasks are run after all JavaScript
+functions on the current stack are done executing.
+This allows escaping the functionality of the `timeout` and
+`breakOnSigint` options.
 
 For example, the following code executed by `vm.runInNewContext()` with a
 timeout of 5 milliseconds schedules an infinite loop to run after a promise
@@ -1240,21 +1261,52 @@ resolves. The scheduled loop is never interrupted by the timeout:
 const vm = require('vm');
 
 function loop() {
+  console.log('entering loop');
   while (1) console.log(Date.now());
 }
 
 vm.runInNewContext(
-  'Promise.resolve().then(loop);',
+  'Promise.resolve().then(() => loop());',
   { loop, console },
   { timeout: 5 }
 );
+// This prints *before* 'entering loop' (!)
+console.log('done executing');
 ```
 
-This issue also occurs when the `loop()` call is scheduled using
-the `process.nextTick()` and `queueMicrotask()` functions.
+This can be addressed by passing `microtaskMode: 'afterEvaluate'` to the code
+that creates the `Context`:
 
-This issue occurs because all contexts share the same microtask and nextTick
-queues.
+```js
+const vm = require('vm');
+
+function loop() {
+  while (1) console.log(Date.now());
+}
+
+vm.runInNewContext(
+  'Promise.resolve().then(() => loop());',
+  { loop, console },
+  { timeout: 5, microtaskMode: 'afterEvaluate' }
+);
+```
+
+In this case, the microtask scheduled through `promise.then()` will be run
+before returning from `vm.runInNewContext()`, and will be interrupted
+by the `timeout` functionality. This applies only to code running in a
+`vm.Context`, so e.g. [`vm.runInThisContext()`][] does not take this option.
+
+Promise callbacks are entered into the microtask queue of the context in which
+they were created. For example, if `() => loop()` is replaced with just `loop`
+in the above example, then `loop` will be pushed into the global microtask
+queue, because it is a function from the outer (main) context, and thus will
+also be able to escape the timeout.
+
+If asynchronous scheduling functions such as `process.nextTick()`,
+`queueMicrotask()`, `setTimeout()`, `setImmediate()`, etc. are made available
+inside a `vm.Context`, functions passed to them will be added to global queues,
+which are shared by all contexts. Therefore, callbacks passed to those functions
+are not controllable through the timeout either.
 
 [`ERR_VM_DYNAMIC_IMPORT_CALLBACK_MISSING`]: errors.html#ERR_VM_DYNAMIC_IMPORT_CALLBACK_MISSING
 [`ERR_VM_MODULE_STATUS`]: errors.html#ERR_VM_MODULE_STATUS

lib/vm.js

@@ -29,6 +29,7 @@ const {
 
 const {
   ContextifyScript,
+  MicrotaskQueue,
   makeContext,
   isContext: _isContext,
   constants,
@@ -186,6 +187,7 @@ function getContextOptions(options) {
     name: options.contextName,
     origin: options.contextOrigin,
     codeGeneration: undefined,
+    microtaskMode: options.microtaskMode,
   };
   if (contextOptions.name !== undefined)
     validateString(contextOptions.name, 'options.contextName');
@@ -201,6 +203,8 @@ function getContextOptions(options) {
       validateBoolean(wasm, 'options.contextCodeGeneration.wasm');
     contextOptions.codeGeneration = { strings, wasm };
   }
+  if (options.microtaskMode !== undefined)
+    validateString(options.microtaskMode, 'options.microtaskMode');
   return contextOptions;
 }
 
@@ -222,7 +226,8 @@ function createContext(contextObject = {}, options = {}) {
   const {
     name = `VM Context ${defaultContextNameIndex++}`,
     origin,
-    codeGeneration
+    codeGeneration,
+    microtaskMode
   } = options;
 
   validateString(name, 'options.name');
@@ -239,7 +244,22 @@ function createContext(contextObject = {}, options = {}) {
     validateBoolean(wasm, 'options.codeGeneration.wasm');
   }
 
-  makeContext(contextObject, name, origin, strings, wasm);
+  let microtaskQueue = null;
+  if (microtaskMode !== undefined) {
+    validateString(microtaskMode, 'options.microtaskMode');
+
+    if (microtaskMode === 'afterEvaluate') {
+      microtaskQueue = new MicrotaskQueue();
+    } else {
+      throw new ERR_INVALID_ARG_VALUE(
+        'options.microtaskQueue',
+        microtaskQueue,
+        'must be \'afterEvaluate\' or undefined'
+      );
+    }
+  }
+
+  makeContext(contextObject, name, origin, strings, wasm, microtaskQueue);
   return contextObject;
 }
 

src/env.h

@@ -433,6 +433,7 @@ constexpr size_t kFsStatsBufferLength =
   V(i18n_converter_template, v8::ObjectTemplate)                               \
   V(libuv_stream_wrap_ctor_template, v8::FunctionTemplate)                     \
   V(message_port_constructor_template, v8::FunctionTemplate)                   \
+  V(microtask_queue_ctor_template, v8::FunctionTemplate)                       \
   V(pipe_constructor_template, v8::FunctionTemplate)                           \
   V(promise_wrap_template, v8::ObjectTemplate)                                 \
   V(sab_lifetimepartner_constructor_template, v8::FunctionTemplate)            \

src/module_wrap.cc

@@ -35,6 +35,7 @@ using v8::IntegrityLevel;
 using v8::Isolate;
 using v8::Local;
 using v8::MaybeLocal;
+using v8::MicrotaskQueue;
 using v8::Module;
 using v8::Number;
 using v8::Object;
@@ -106,15 +107,15 @@ void ModuleWrap::New(const FunctionCallbackInfo<Value>& args) {
   Local<String> url = args[0].As<String>();
 
   Local<Context> context;
+  ContextifyContext* contextify_context = nullptr;
   if (args[1]->IsUndefined()) {
     context = that->CreationContext();
   } else {
     CHECK(args[1]->IsObject());
-    ContextifyContext* sandbox =
-        ContextifyContext::ContextFromContextifiedSandbox(
-            env, args[1].As<Object>());
-    CHECK_NOT_NULL(sandbox);
-    context = sandbox->context();
+    contextify_context = ContextifyContext::ContextFromContextifiedSandbox(
+        env, args[1].As<Object>());
+    CHECK_NOT_NULL(contextify_context);
+    context = contextify_context->context();
   }
 
   Local<Integer> line_offset;
@@ -224,6 +225,7 @@ void ModuleWrap::New(const FunctionCallbackInfo<Value>& args) {
   }
 
   obj->context_.Reset(isolate, context);
+  obj->contextify_context_ = contextify_context;
 
   env->hash_to_module_map.emplace(module->GetIdentityHash(), obj);
 
@@ -319,6 +321,11 @@ void ModuleWrap::Evaluate(const FunctionCallbackInfo<Value>& args) {
   Local<Context> context = obj->context_.Get(isolate);
   Local<Module> module = obj->module_.Get(isolate);
 
+  ContextifyContext* contextify_context = obj->contextify_context_;
+  std::shared_ptr<MicrotaskQueue> microtask_queue;
+  if (contextify_context != nullptr)
+      microtask_queue = contextify_context->microtask_queue();
+
   // module.evaluate(timeout, breakOnSigint)
   CHECK_EQ(args.Length(), 2);
 
@@ -334,18 +341,24 @@ void ModuleWrap::Evaluate(const FunctionCallbackInfo<Value>& args) {
   bool timed_out = false;
   bool received_signal = false;
   MaybeLocal<Value> result;
+  auto run = [&]() {
+    MaybeLocal<Value> result = module->Evaluate(context);
+    if (!result.IsEmpty() && microtask_queue)
+      microtask_queue->PerformCheckpoint(isolate);
+    return result;
+  };
   if (break_on_sigint && timeout != -1) {
     Watchdog wd(isolate, timeout, &timed_out);
     SigintWatchdog swd(isolate, &received_signal);
-    result = module->Evaluate(context);
+    result = run();
   } else if (break_on_sigint) {
     SigintWatchdog swd(isolate, &received_signal);
-    result = module->Evaluate(context);
+    result = run();
   } else if (timeout != -1) {
     Watchdog wd(isolate, timeout, &timed_out);
-    result = module->Evaluate(context);
+    result = run();
   } else {
-    result = module->Evaluate(context);
+    result = run();
   }
 
   if (result.IsEmpty()) {

src/module_wrap.h

@@ -12,6 +12,10 @@ namespace node {
 
 class Environment;
 
+namespace contextify {
+class ContextifyContext;
+}
+
 namespace loader {
 
 enum ScriptType : int {
@@ -82,12 +86,13 @@ class ModuleWrap : public BaseObject {
   static ModuleWrap* GetFromModule(node::Environment*, v8::Local<v8::Module>);
 
   v8::Global<v8::Function> synthetic_evaluation_steps_;
-  bool synthetic_ = false;
   v8::Global<v8::Module> module_;
   v8::Global<v8::String> url_;
-  bool linked_ = false;
   std::unordered_map<std::string, v8::Global<v8::Promise>> resolve_cache_;
   v8::Global<v8::Context> context_;
+  contextify::ContextifyContext* contextify_context_ = nullptr;
+  bool synthetic_ = false;
+  bool linked_ = false;
   uint32_t id_;
 };
 

src/node_contextify.cc

@@ -54,6 +54,8 @@ using v8::Maybe;
 using v8::MaybeLocal;
 using v8::MeasureMemoryExecution;
 using v8::MeasureMemoryMode;
+using v8::MicrotaskQueue;
+using v8::MicrotasksPolicy;
 using v8::Name;
 using v8::NamedPropertyHandlerConfiguration;
 using v8::Number;
@@ -108,7 +110,10 @@ Local<Name> Uint32ToName(Local<Context> context, uint32_t index) {
 
 ContextifyContext::ContextifyContext(
     Environment* env,
-    Local<Object> sandbox_obj, const ContextOptions& options) : env_(env) {
+    Local<Object> sandbox_obj,
+    const ContextOptions& options)
+  : env_(env),
+    microtask_queue_wrap_(options.microtask_queue_wrap) {
   MaybeLocal<Context> v8_context = CreateV8Context(env, sandbox_obj, options);
 
   // Allocation failure, maximum call stack size reached, termination, etc.
@@ -188,7 +193,13 @@ MaybeLocal<Context> ContextifyContext::CreateV8Context(
 
   object_template->SetHandler(config);
   object_template->SetHandler(indexed_config);
-  Local<Context> ctx = Context::New(env->isolate(), nullptr, object_template);
+  Local<Context> ctx = Context::New(
+      env->isolate(),
+      nullptr,  // extensions
+      object_template,
+      {},       // global object
+      {},       // deserialization callback
+      microtask_queue() ? microtask_queue().get() : nullptr);
   if (ctx.IsEmpty()) return MaybeLocal<Context>();
   // Only partially initialize the context - the primordials are left out
   // and only initialized when necessary.
@@ -247,7 +258,7 @@ void ContextifyContext::Init(Environment* env, Local<Object> target) {
 void ContextifyContext::MakeContext(const FunctionCallbackInfo<Value>& args) {
   Environment* env = Environment::GetCurrent(args);
 
-  CHECK_EQ(args.Length(), 5);
+  CHECK_EQ(args.Length(), 6);
   CHECK(args[0]->IsObject());
   Local<Object> sandbox = args[0].As<Object>();
 
@@ -273,6 +284,13 @@ void ContextifyContext::MakeContext(const FunctionCallbackInfo<Value>& args) {
   CHECK(args[4]->IsBoolean());
   options.allow_code_gen_wasm = args[4].As<Boolean>();
 
+  if (args[5]->IsObject() &&
+      !env->microtask_queue_ctor_template().IsEmpty() &&
+      env->microtask_queue_ctor_template()->HasInstance(args[5])) {
+    options.microtask_queue_wrap.reset(
+        Unwrap<MicrotaskQueueWrap>(args[5].As<Object>()));
+  }
+
   TryCatchScope try_catch(env);
   auto context_ptr = std::make_unique<ContextifyContext>(env, sandbox, options);
 
@@ -845,6 +863,7 @@ void ContextifyScript::RunInThisContext(
               display_errors,
               break_on_sigint,
               break_on_first_line,
+              nullptr,  // microtask_queue
               args);
 
   TRACE_EVENT_NESTABLE_ASYNC_END0(
@@ -891,6 +910,7 @@ void ContextifyScript::RunInContext(const FunctionCallbackInfo<Value>& args) {
               display_errors,
               break_on_sigint,
               break_on_first_line,
+              contextify_context->microtask_queue(),
               args);
 
   TRACE_EVENT_NESTABLE_ASYNC_END0(
@@ -902,6 +922,7 @@ bool ContextifyScript::EvalMachine(Environment* env,
                                    const bool display_errors,
                                    const bool break_on_sigint,
                                    const bool break_on_first_line,
+                                   std::shared_ptr<MicrotaskQueue> mtask_queue,
                                    const FunctionCallbackInfo<Value>& args) {
   if (!env->can_call_into_js())
     return false;
@@ -926,18 +947,24 @@ bool ContextifyScript::EvalMachine(Environment* env,
   MaybeLocal<Value> result;
   bool timed_out = false;
   bool received_signal = false;
+  auto run = [&]() {
+    MaybeLocal<Value> result = script->Run(env->context());
+    if (!result.IsEmpty() && mtask_queue)
+      mtask_queue->PerformCheckpoint(env->isolate());
+    return result;
+  };
   if (break_on_sigint && timeout != -1) {
     Watchdog wd(env->isolate(), timeout, &timed_out);
     SigintWatchdog swd(env->isolate(), &received_signal);
-    result = script->Run(env->context());
+    result = run();
   } else if (break_on_sigint) {
     SigintWatchdog swd(env->isolate(), &received_signal);
-    result = script->Run(env->context());
+    result = run();
   } else if (timeout != -1) {
     Watchdog wd(env->isolate(), timeout, &timed_out);
-    result = script->Run(env->context());
+    result = run();
   } else {
-    result = script->Run(env->context());
+    result = run();
   }
 
   // Convert the termination exception into a regular exception.
@@ -1232,6 +1259,43 @@ static void MeasureMemory(const FunctionCallbackInfo<Value>& args) {
   args.GetReturnValue().Set(promise);
 }
 
+MicrotaskQueueWrap::MicrotaskQueueWrap(Environment* env, Local<Object> obj)
+  : BaseObject(env, obj),
+    microtask_queue_(
+        MicrotaskQueue::New(env->isolate(), MicrotasksPolicy::kExplicit)) {
+  MakeWeak();
+}
+
+const std::shared_ptr<MicrotaskQueue>&
+MicrotaskQueueWrap::microtask_queue() const {
+  return microtask_queue_;
+}
+
+void MicrotaskQueueWrap::New(const FunctionCallbackInfo<Value>& args) {
+  CHECK(args.IsConstructCall());
+  new MicrotaskQueueWrap(Environment::GetCurrent(args), args.This());
+}
+
+void MicrotaskQueueWrap::Init(Environment* env, Local<Object> target) {
+  HandleScope scope(env->isolate());
+  Local<String> class_name =
+      FIXED_ONE_BYTE_STRING(env->isolate(), "MicrotaskQueue");
+
+  Local<FunctionTemplate> tmpl = env->NewFunctionTemplate(New);
+  tmpl->InstanceTemplate()->SetInternalFieldCount(
+      ContextifyScript::kInternalFieldCount);
+  tmpl->SetClassName(class_name);
+
+  if (target->Set(env->context(),
+                  class_name,
+                  tmpl->GetFunction(env->context()).ToLocalChecked())
+          .IsNothing()) {
+    return;
+  }
+  env->set_microtask_queue_ctor_template(tmpl);
+}
+
+
 void Initialize(Local<Object> target,
                 Local<Value> unused,
                 Local<Context> context,
@@ -1240,6 +1304,7 @@ void Initialize(Local<Object> target,
   Isolate* isolate = env->isolate();
   ContextifyContext::Init(env, target);
   ContextifyScript::Init(env, target);
+  MicrotaskQueueWrap::Init(env, target);
 
   env->SetMethod(target, "startSigintWatchdog", StartSigintWatchdog);
   env->SetMethod(target, "stopSigintWatchdog", StopSigintWatchdog);

src/node_contextify.h

@@ -10,11 +10,32 @@
 namespace node {
 namespace contextify {
 
+class MicrotaskQueueWrap : public BaseObject {
+ public:
+  MicrotaskQueueWrap(Environment* env, v8::Local<v8::Object> obj);
+
+  const std::shared_ptr<v8::MicrotaskQueue>& microtask_queue() const;
+
+  static void Init(Environment* env, v8::Local<v8::Object> target);
+  static void New(const v8::FunctionCallbackInfo<v8::Value>& args);
+
+  // This could have methods for running the microtask queue, if we ever decide
+  // to make that fully customizable from userland.
+
+  SET_NO_MEMORY_INFO()
+  SET_MEMORY_INFO_NAME(MicrotaskQueueWrap)
+  SET_SELF_SIZE(MicrotaskQueueWrap)
+
+ private:
+  std::shared_ptr<v8::MicrotaskQueue> microtask_queue_;
+};
+
 struct ContextOptions {
   v8::Local<v8::String> name;
   v8::Local<v8::String> origin;
   v8::Local<v8::Boolean> allow_code_gen_strings;
   v8::Local<v8::Boolean> allow_code_gen_wasm;
+  BaseObjectPtr<MicrotaskQueueWrap> microtask_queue_wrap;
 };
 
 class ContextifyContext {
@@ -53,6 +74,11 @@ class ContextifyContext {
         context()->GetEmbedderData(ContextEmbedderIndex::kSandboxObject));
   }
 
+  inline std::shared_ptr<v8::MicrotaskQueue> microtask_queue() const {
+    if (!microtask_queue_wrap_) return {};
+    return microtask_queue_wrap_->microtask_queue();
+  }
+
 
   template <typename T>
   static ContextifyContext* Get(const v8::PropertyCallbackInfo<T>& args);
@@ -102,6 +128,7 @@ class ContextifyContext {
       const v8::PropertyCallbackInfo<v8::Boolean>& args);
   Environment* const env_;
   v8::Global<v8::Context> context_;
+  BaseObjectPtr<MicrotaskQueueWrap> microtask_queue_wrap_;
 };
 
 class ContextifyScript : public BaseObject {
@@ -125,6 +152,7 @@ class ContextifyScript : public BaseObject {
                           const bool display_errors,
                           const bool break_on_sigint,
                           const bool break_on_first_line,
+                          std::shared_ptr<v8::MicrotaskQueue> microtask_queue,
                           const v8::FunctionCallbackInfo<v8::Value>& args);
 
   inline uint32_t id() { return id_; }

test/known_issues/known_issues.status

@@ -14,9 +14,6 @@ test-vm-timeout-escape-queuemicrotask: SKIP
 [$system==win32]
 
 [$system==linux]
-# https://github.com/nodejs/node/pull/23743
-# https://github.com/nodejs/node/issues/3020
-test-vm-timeout-escape-promise: PASS,FLAKY
 
 [$system==macos]
 

test/known_issues/test-vm-timeout-escape-queuemicrotask.js

@@ -35,7 +35,7 @@ assert.throws(() => {
       queueMicrotask,
       loop
     },
-    { timeout }
+    { timeout, microtaskMode: 'afterScriptRun' }
   );
 }, {
   code: 'ERR_SCRIPT_EXECUTION_TIMEOUT',

test/parallel/test-vm-timeout-escape-promise-2.js

@@ -0,0 +1,38 @@
+'use strict';
+// https://github.com/nodejs/node/issues/3020
+// Promises used to allow code to escape the timeout
+// set for runInContext, runInNewContext, and runInThisContext.
+
+require('../common');
+const assert = require('assert');
+const vm = require('vm');
+
+const NS_PER_MS = 1000000n;
+
+const hrtime = process.hrtime.bigint;
+
+function loop() {
+  const start = hrtime();
+  while (1) {
+    const current = hrtime();
+    const span = (current - start) / NS_PER_MS;
+    if (span >= 100n) {
+      throw new Error(
+        `escaped timeout at ${span} milliseconds!`);
+    }
+  }
+}
+
+assert.throws(() => {
+  vm.runInNewContext(
+    'Promise.resolve().then(() => loop());',
+    {
+      hrtime,
+      loop
+    },
+    { timeout: 10, microtaskMode: 'afterEvaluate' }
+  );
+}, {
+  code: 'ERR_SCRIPT_EXECUTION_TIMEOUT',
+  message: 'Script execution timed out after 10ms'
+});

test/parallel/test-vm-timeout-escape-promise-module-2.js

@@ -0,0 +1,42 @@
+// Flags: --experimental-vm-modules
+'use strict';
+
+// https://github.com/nodejs/node/issues/3020
+// Promises used to allow code to escape the timeout
+// set for runInContext, runInNewContext, and runInThisContext.
+
+const common = require('../common');
+const assert = require('assert');
+const vm = require('vm');
+
+const NS_PER_MS = 1000000n;
+
+const hrtime = process.hrtime.bigint;
+
+function loop() {
+  const start = hrtime();
+  while (1) {
+    const current = hrtime();
+    const span = (current - start) / NS_PER_MS;
+    if (span >= 100n) {
+      throw new Error(
+        `escaped timeout at ${span} milliseconds!`);
+    }
+  }
+}
+
+assert.rejects(async () => {
+  const module = new vm.SourceTextModule(
+    'Promise.resolve().then(() => loop());',
+    {
+      context: vm.createContext({
+        hrtime,
+        loop
+      }, { microtaskMode: 'afterEvaluate' })
+    });
+  await module.link(common.mustNotCall());
+  await module.evaluate({ timeout: 10 });
+}, {
+  code: 'ERR_SCRIPT_EXECUTION_TIMEOUT',
+  message: 'Script execution timed out after 10ms'
+});

test/parallel/test-vm-timeout-escape-promise-module.js

@@ -0,0 +1,42 @@
+// Flags: --experimental-vm-modules
+'use strict';
+
+// https://github.com/nodejs/node/issues/3020
+// Promises used to allow code to escape the timeout
+// set for runInContext, runInNewContext, and runInThisContext.
+
+const common = require('../common');
+const assert = require('assert');
+const vm = require('vm');
+
+const NS_PER_MS = 1000000n;
+
+const hrtime = process.hrtime.bigint;
+
+function loop() {
+  const start = hrtime();
+  while (1) {
+    const current = hrtime();
+    const span = (current - start) / NS_PER_MS;
+    if (span >= 100n) {
+      throw new Error(
+        `escaped timeout at ${span} milliseconds!`);
+    }
+  }
+}
+
+assert.rejects(async () => {
+  const module = new vm.SourceTextModule(
+    'Promise.resolve().then(() => loop()); loop();',
+    {
+      context: vm.createContext({
+        hrtime,
+        loop
+      }, { microtaskMode: 'afterEvaluate' })
+    });
+  await module.link(common.mustNotCall());
+  await module.evaluate({ timeout: 5 });
+}, {
+  code: 'ERR_SCRIPT_EXECUTION_TIMEOUT',
+  message: 'Script execution timed out after 5ms'
+});

test/parallel/test-vm-timeout-escape-promise.js

@@ -1,8 +1,8 @@
 'use strict';
 
 // https://github.com/nodejs/node/issues/3020
-// Promises, nextTick, and queueMicrotask allow code to escape the timeout
-// set for runInContext, runInNewContext, and runInThisContext
+// Promises used to allow code to escape the timeout
+// set for runInContext, runInNewContext, and runInThisContext.
 
 require('../common');
 const assert = require('assert');
@@ -26,12 +26,12 @@ function loop() {
 
 assert.throws(() => {
   vm.runInNewContext(
-    'Promise.resolve().then(loop); loop();',
+    'Promise.resolve().then(() => loop()); loop();',
     {
       hrtime,
       loop
     },
-    { timeout: 5 }
+    { timeout: 5, microtaskMode: 'afterEvaluate' }
   );
 }, {
   code: 'ERR_SCRIPT_EXECUTION_TIMEOUT',