Revert "feat: add "unhandledrejection" event support (#12994) (#15080)" (#15210)

This reverts commit 1a7259b04b7229f6350a7a7c21b50497b5c80c17.

10 files changed, 10 insertions, 213 deletions

diff --git a/cli/dts/lib.deno.shared_globals.d.ts b/cli/dts/lib.deno.shared_globals.d.ts
index abf5e41fb..fc40bb54e 100644
--- a/cli/dts/lib.deno.shared_globals.d.ts
+++ b/cli/dts/lib.deno.shared_globals.d.ts
@@ -400,17 +400,6 @@ declare class ErrorEvent extends Event {
   constructor(type: string, eventInitDict?: ErrorEventInit);
 }
 
-interface PromiseRejectionEventInit extends EventInit {
-  promise: Promise<any>;
-  reason?: any;
-}
-
-declare class PromiseRejectionEvent extends Event {
-  readonly promise: Promise<any>;
-  readonly reason: any;
-  constructor(type: string, eventInitDict?: PromiseRejectionEventInit);
-}
-
 interface AbstractWorkerEventMap {
   "error": ErrorEvent;
 }
diff --git a/cli/tests/integration/run_tests.rs b/cli/tests/integration/run_tests.rs
index 06cb1629b..bb46fe1b5 100644
--- a/cli/tests/integration/run_tests.rs
+++ b/cli/tests/integration/run_tests.rs
@@ -2783,8 +2783,3 @@ itest!(followup_dyn_import_resolved {
   args: "run --unstable --allow-read followup_dyn_import_resolves/main.ts",
   output: "followup_dyn_import_resolves/main.ts.out",
 });
-
-itest!(unhandled_rejection {
-  args: "run --allow-read unhandled_rejection.js",
-  output: "unhandled_rejection.js.out",
-});
diff --git a/cli/tests/testdata/unhandled_rejection.js b/cli/tests/testdata/unhandled_rejection.js
deleted file mode 100644
index 352e861b4..000000000
--- a/cli/tests/testdata/unhandled_rejection.js
+++ /dev/null
@@ -1,11 +0,0 @@
-globalThis.addEventListener("unhandledrejection", (e) => {
-  console.log("unhandled rejection at:", e.promise, "reason:", e.reason);
-  e.preventDefault();
-});
-
-function Foo() {
-  this.bar = Promise.reject(new Error("bar not available"));
-}
-
-new Foo();
-Promise.reject();
diff --git a/cli/tests/testdata/unhandled_rejection.js.out b/cli/tests/testdata/unhandled_rejection.js.out
deleted file mode 100644
index 4c41795ce..000000000
--- a/cli/tests/testdata/unhandled_rejection.js.out
+++ /dev/null
@@ -1,8 +0,0 @@
-unhandled rejection at: Promise {
-  <rejected> Error: bar not available
-    at new Foo (file:///[WILDCARD]/testdata/unhandled_rejection.js:7:29)
-    at file:///[WILDCARD]/testdata/unhandled_rejection.js:10:1
-} reason: Error: bar not available
-    at new Foo (file:///[WILDCARD]/testdata/unhandled_rejection.js:7:29)
-    at file:///[WILDCARD]/testdata/unhandled_rejection.js:10:1
-unhandled rejection at: Promise { <rejected> undefined } reason: undefined
diff --git a/core/01_core.js b/core/01_core.js
index 21376b695..156300327 100644
--- a/core/01_core.js
+++ b/core/01_core.js
@@ -268,10 +268,6 @@
     terminate: opSync.bind(null, "op_terminate"),
     opNames: opSync.bind(null, "op_op_names"),
     eventLoopHasMoreWork: opSync.bind(null, "op_event_loop_has_more_work"),
-    setPromiseRejectCallback: opSync.bind(
-      null,
-      "op_set_promise_reject_callback",
-    ),
   });
 
   ObjectAssign(globalThis.__bootstrap, { core });
diff --git a/core/bindings.rs b/core/bindings.rs
index c9e27f087..49dc62c0e 100644
--- a/core/bindings.rs
+++ b/core/bindings.rs
@@ -282,6 +282,14 @@ pub extern "C" fn promise_reject_callback(message: v8::PromiseRejectMessage) {
   let state_rc = JsRuntime::state(scope);
   let mut state = state_rc.borrow_mut();
 
+  // Node compat: perform synchronous process.emit("unhandledRejection").
+  //
+  // Note the callback follows the (type, promise, reason) signature of Node's
+  // internal promiseRejectHandler from lib/internal/process/promises.js, not
+  // the (promise, reason) signature of the "unhandledRejection" event listener.
+  //
+  // Short-circuits Deno's regular unhandled rejection logic because that's
+  // a) asynchronous, and b) always terminates.
   if let Some(js_promise_reject_cb) = state.js_promise_reject_cb.clone() {
     let js_uncaught_exception_cb = state.js_uncaught_exception_cb.clone();
 
@@ -323,7 +331,6 @@ pub extern "C" fn promise_reject_callback(message: v8::PromiseRejectMessage) {
     }
 
     if tc_scope.has_caught() {
-      // TODO(bartlomieju): ensure that TODO provided below is still valid.
       // If we get here, an exception was thrown by the unhandledRejection
       // handler and there is ether no uncaughtException handler or the
       // handler threw an exception of its own.
@@ -341,6 +348,7 @@ pub extern "C" fn promise_reject_callback(message: v8::PromiseRejectMessage) {
   } else {
     let promise = message.get_promise();
     let promise_global = v8::Global::new(scope, promise);
+
     match message.get_event() {
       PromiseRejectWithNoHandler => {
         let error = message.get_value().unwrap();
diff --git a/core/ops_builtin_v8.rs b/core/ops_builtin_v8.rs
index a17e273f3..39469c0ad 100644
--- a/core/ops_builtin_v8.rs
+++ b/core/ops_builtin_v8.rs
@@ -48,9 +48,6 @@ pub(crate) fn init_builtins_v8() -> Vec<OpDecl> {
     op_apply_source_map::decl(),
     op_set_format_exception_callback::decl(),
     op_event_loop_has_more_work::decl(),
-    op_store_pending_promise_exception::decl(),
-    op_remove_pending_promise_exception::decl(),
-    op_has_pending_promise_exception::decl(),
   ]
 }
 
@@ -795,48 +792,3 @@ fn op_set_format_exception_callback<'a>(
 fn op_event_loop_has_more_work(scope: &mut v8::HandleScope) -> bool {
   JsRuntime::event_loop_pending_state(scope).is_pending()
 }
-
-#[op(v8)]
-fn op_store_pending_promise_exception<'a>(
-  scope: &mut v8::HandleScope<'a>,
-  promise: serde_v8::Value<'a>,
-  reason: serde_v8::Value<'a>,
-) {
-  let state_rc = JsRuntime::state(scope);
-  let mut state = state_rc.borrow_mut();
-  let promise_value =
-    v8::Local::<v8::Promise>::try_from(promise.v8_value).unwrap();
-  let promise_global = v8::Global::new(scope, promise_value);
-  let error_global = v8::Global::new(scope, reason.v8_value);
-  state
-    .pending_promise_exceptions
-    .insert(promise_global, error_global);
-}
-
-#[op(v8)]
-fn op_remove_pending_promise_exception<'a>(
-  scope: &mut v8::HandleScope<'a>,
-  promise: serde_v8::Value<'a>,
-) {
-  let state_rc = JsRuntime::state(scope);
-  let mut state = state_rc.borrow_mut();
-  let promise_value =
-    v8::Local::<v8::Promise>::try_from(promise.v8_value).unwrap();
-  let promise_global = v8::Global::new(scope, promise_value);
-  state.pending_promise_exceptions.remove(&promise_global);
-}
-
-#[op(v8)]
-fn op_has_pending_promise_exception<'a>(
-  scope: &mut v8::HandleScope<'a>,
-  promise: serde_v8::Value<'a>,
-) -> bool {
-  let state_rc = JsRuntime::state(scope);
-  let state = state_rc.borrow();
-  let promise_value =
-    v8::Local::<v8::Promise>::try_from(promise.v8_value).unwrap();
-  let promise_global = v8::Global::new(scope, promise_value);
-  state
-    .pending_promise_exceptions
-    .contains_key(&promise_global)
-}
diff --git a/ext/web/02_event.js b/ext/web/02_event.js
index 105c7d3c4..5d8f69673 100644
--- a/ext/web/02_event.js
+++ b/ext/web/02_event.js
@@ -1278,58 +1278,6 @@
     [SymbolToStringTag] = "ProgressEvent";
   }
 
-  class PromiseRejectionEvent extends Event {
-    #promise = null;
-    #reason = null;
-
-    get promise() {
-      return this.#promise;
-    }
-    get reason() {
-      return this.#reason;
-    }
-
-    constructor(
-      type,
-      {
-        bubbles,
-        cancelable,
-        composed,
-        promise,
-        reason,
-      } = {},
-    ) {
-      super(type, {
-        bubbles: bubbles,
-        cancelable: cancelable,
-        composed: composed,
-      });
-
-      this.#promise = promise;
-      this.#reason = reason;
-    }
-
-    [SymbolFor("Deno.privateCustomInspect")](inspect) {
-      return inspect(consoleInternal.createFilteredInspectProxy({
-        object: this,
-        evaluate: this instanceof PromiseRejectionEvent,
-        keys: [
-          ...EVENT_PROPS,
-          "promise",
-          "reason",
-        ],
-      }));
-    }
-
-    // TODO(lucacasonato): remove when this interface is spec aligned
-    [SymbolToStringTag] = "PromiseRejectionEvent";
-  }
-
-  defineEnumerableProps(PromiseRejectionEvent, [
-    "promise",
-    "reason",
-  ]);
-
   const _eventHandlers = Symbol("eventHandlers");
 
   function makeWrappedHandler(handler, isSpecialErrorEventHandler) {
@@ -1478,7 +1426,6 @@
   window.MessageEvent = MessageEvent;
   window.CustomEvent = CustomEvent;
   window.ProgressEvent = ProgressEvent;
-  window.PromiseRejectionEvent = PromiseRejectionEvent;
   window.dispatchEvent = EventTarget.prototype.dispatchEvent;
   window.addEventListener = EventTarget.prototype.addEventListener;
   window.removeEventListener = EventTarget.prototype.removeEventListener;
diff --git a/runtime/js/99_main.js b/runtime/js/99_main.js
index 47c2ab9b1..c13faa936 100644
--- a/runtime/js/99_main.js
+++ b/runtime/js/99_main.js
@@ -11,10 +11,6 @@ delete Intl.v8BreakIterator;
 ((window) => {
   const core = Deno.core;
   const {
-    ArrayPrototypeIndexOf,
-    ArrayPrototypePush,
-    ArrayPrototypeShift,
-    ArrayPrototypeSplice,
     ArrayPrototypeMap,
     DateNow,
     Error,
@@ -31,11 +27,7 @@ delete Intl.v8BreakIterator;
     SymbolFor,
     SymbolIterator,
     PromisePrototypeThen,
-    SafeWeakMap,
     TypeError,
-    WeakMapPrototypeDelete,
-    WeakMapPrototypeGet,
-    WeakMapPrototypeSet,
   } = window.__bootstrap.primordials;
   const util = window.__bootstrap.util;
   const eventTarget = window.__bootstrap.eventTarget;
@@ -241,7 +233,6 @@ delete Intl.v8BreakIterator;
 
   function runtimeStart(runtimeOptions, source) {
     core.setMacrotaskCallback(timers.handleTimerMacrotask);
-    core.setMacrotaskCallback(promiseRejectMacrotaskCallback);
     core.setWasmStreamingCallback(fetch.handleWasmStreaming);
     core.opSync("op_set_format_exception_callback", formatException);
     version.setVersions(
@@ -420,7 +411,6 @@ delete Intl.v8BreakIterator;
     PerformanceEntry: util.nonEnumerable(performance.PerformanceEntry),
     PerformanceMark: util.nonEnumerable(performance.PerformanceMark),
     PerformanceMeasure: util.nonEnumerable(performance.PerformanceMeasure),
-    PromiseRejectionEvent: util.nonEnumerable(PromiseRejectionEvent),
     ProgressEvent: util.nonEnumerable(ProgressEvent),
     ReadableStream: util.nonEnumerable(streams.ReadableStream),
     ReadableStreamDefaultReader: util.nonEnumerable(
@@ -563,60 +553,6 @@ delete Intl.v8BreakIterator;
     postMessage: util.writable(postMessage),
   };
 
-  const pendingRejections = [];
-  const pendingRejectionsReasons = new SafeWeakMap();
-
-  function promiseRejectCallback(type, promise, reason) {
-    switch (type) {
-      case 0: {
-        core.opSync("op_store_pending_promise_exception", promise, reason);
-        ArrayPrototypePush(pendingRejections, promise);
-        WeakMapPrototypeSet(pendingRejectionsReasons, promise, reason);
-        break;
-      }
-      case 1: {
-        core.opSync("op_remove_pending_promise_exception", promise);
-        const index = ArrayPrototypeIndexOf(pendingRejections, promise);
-        if (index > -1) {
-          ArrayPrototypeSplice(pendingRejections, index, 1);
-          WeakMapPrototypeDelete(pendingRejectionsReasons, promise);
-        }
-        break;
-      }
-      default:
-        return;
-    }
-  }
-
-  function promiseRejectMacrotaskCallback() {
-    while (pendingRejections.length > 0) {
-      const promise = ArrayPrototypeShift(pendingRejections);
-      const hasPendingException = core.opSync(
-        "op_has_pending_promise_exception",
-        promise,
-      );
-      const reason = WeakMapPrototypeGet(pendingRejectionsReasons, promise);
-      WeakMapPrototypeDelete(pendingRejectionsReasons, promise);
-
-      if (!hasPendingException) {
-        return;
-      }
-
-      const event = new PromiseRejectionEvent("unhandledrejection", {
-        cancelable: true,
-        promise,
-        reason,
-      });
-      globalThis.dispatchEvent(event);
-
-      // If event was not prevented we will let Rust side handle it.
-      if (event.defaultPrevented) {
-        core.opSync("op_remove_pending_promise_exception", promise);
-      }
-    }
-    return true;
-  }
-
   let hasBootstrapped = false;
 
   function bootstrapMainRuntime(runtimeOptions) {
@@ -649,10 +585,6 @@ delete Intl.v8BreakIterator;
     defineEventHandler(window, "load");
     defineEventHandler(window, "beforeunload");
     defineEventHandler(window, "unload");
-    defineEventHandler(window, "unhandledrejection");
-
-    core.setPromiseRejectCallback(promiseRejectCallback);
-
     const isUnloadDispatched = SymbolFor("isUnloadDispatched");
     // Stores the flag for checking whether unload is dispatched or not.
     // This prevents the recursive dispatches of unload events.
@@ -753,10 +685,6 @@ delete Intl.v8BreakIterator;
 
     defineEventHandler(self, "message");
     defineEventHandler(self, "error", undefined, true);
-    defineEventHandler(self, "unhandledrejection");
-
-    core.setPromiseRejectCallback(promiseRejectCallback);
-
     // `Deno.exit()` is an alias to `self.close()`. Setting and exit
     // code using an op in worker context is a no-op.
     os.setExitHandler((_exitCode) => {
diff --git a/tools/wpt/expectation.json b/tools/wpt/expectation.json
index 0d53dd962..56b0b1199 100644
--- a/tools/wpt/expectation.json
+++ b/tools/wpt/expectation.json
@@ -4360,6 +4360,7 @@
           "The CanvasPath interface object should be exposed.",
           "The TextMetrics interface object should be exposed.",
           "The Path2D interface object should be exposed.",
+          "The PromiseRejectionEvent interface object should be exposed.",
           "The EventSource interface object should be exposed.",
           "The XMLHttpRequestEventTarget interface object should be exposed.",
           "The XMLHttpRequestUpload interface object should be exposed.",