Revert realms from deno_core (#16366)

This revert has been discussed at length out-of-band (including with
@andreubotella). The realms work in impeding ongoing event loop and
performance work. We very much want to land realms but it needs to wait
until these lower-level refactors are complete. We hope to bring realms
back in a couple weeks.

5 files changed, 96 insertions, 454 deletions

diff --git a/core/bindings.rs b/core/bindings.rs
index a28a3a132..741ab6336 100644
--- a/core/bindings.rs
+++ b/core/bindings.rs
@@ -7,7 +7,6 @@ use crate::modules::validate_import_assertions;
 use crate::modules::ImportAssertionsKind;
 use crate::modules::ModuleMap;
 use crate::ops::OpCtx;
-use crate::JsRealm;
 use crate::JsRuntime;
 use log::debug;
 use std::option::Option;
@@ -425,15 +424,15 @@ pub extern "C" fn promise_reject_callback(message: v8::PromiseRejectMessage) {
   // SAFETY: `CallbackScope` can be safely constructed from `&PromiseRejectMessage`
   let scope = &mut unsafe { v8::CallbackScope::new(&message) };
 
-  let realm_state_rc = JsRealm::state_from_scope(scope);
+  let state_rc = JsRuntime::state(scope);
+  let mut state = state_rc.borrow_mut();
 
-  if let Some(js_promise_reject_cb) =
-    realm_state_rc.borrow().js_promise_reject_cb.clone()
-  {
+  if let Some(js_promise_reject_cb) = state.js_promise_reject_cb.clone() {
     let tc_scope = &mut v8::TryCatch::new(scope);
     let undefined: v8::Local<v8::Value> = v8::undefined(tc_scope).into();
     let type_ = v8::Integer::new(tc_scope, message.get_event() as i32);
     let promise = message.get_promise();
+    drop(state); // Drop borrow, callbacks can call back into runtime.
 
     let reason = match message.get_event() {
       PromiseRejectWithNoHandler
@@ -456,7 +455,6 @@ pub extern "C" fn promise_reject_callback(message: v8::PromiseRejectMessage) {
       };
 
     if has_unhandled_rejection_handler {
-      let state_rc = JsRuntime::state(tc_scope);
       let mut state = state_rc.borrow_mut();
       if let Some(pending_mod_evaluate) = state.pending_mod_evaluate.as_mut() {
         if !pending_mod_evaluate.has_evaluated {
@@ -467,8 +465,6 @@ pub extern "C" fn promise_reject_callback(message: v8::PromiseRejectMessage) {
       }
     }
   } else {
-    let state_rc = JsRuntime::state(scope);
-    let mut state = state_rc.borrow_mut();
     let promise = message.get_promise();
     let promise_global = v8::Global::new(scope, promise);
     match message.get_event() {
@@ -487,7 +483,7 @@ pub extern "C" fn promise_reject_callback(message: v8::PromiseRejectMessage) {
         // Should not warn. See #1272
       }
     }
-  };
+  }
 }
 
 /// This binding should be used if there's a custom console implementation
diff --git a/core/error.rs b/core/error.rs
index 626f9b6f2..7df5c1efa 100644
--- a/core/error.rs
+++ b/core/error.rs
@@ -1,7 +1,6 @@
 // Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
 
 use crate::runtime::GetErrorClassFn;
-use crate::runtime::JsRealm;
 use crate::runtime::JsRuntime;
 use crate::source_map::apply_source_map;
 use crate::source_map::get_source_line;
@@ -98,7 +97,7 @@ pub fn to_v8_error<'a>(
   get_class: GetErrorClassFn,
   error: &Error,
 ) -> v8::Local<'a, v8::Value> {
-  let cb = JsRealm::state_from_scope(scope)
+  let cb = JsRuntime::state(scope)
     .borrow()
     .js_build_custom_error_cb
     .clone()
@@ -218,10 +217,10 @@ impl JsError {
     let msg = v8::Exception::create_message(scope, exception);
 
     let mut exception_message = None;
-    let realm_state_rc = JsRealm::state_from_scope(scope);
+    let state_rc = JsRuntime::state(scope);
 
     let js_format_exception_cb =
-      realm_state_rc.borrow().js_format_exception_cb.clone();
+      state_rc.borrow().js_format_exception_cb.clone();
     if let Some(format_exception_cb) = js_format_exception_cb {
       let format_exception_cb = format_exception_cb.open(scope);
       let this = v8::undefined(scope).into();
@@ -286,7 +285,6 @@ impl JsError {
       let mut source_line = None;
       let mut source_line_frame_index = None;
       {
-        let state_rc = JsRuntime::state(scope);
         let state = &mut *state_rc.borrow_mut();
 
         // When the stack frame array is empty, but the source location given by
diff --git a/core/ops_builtin_v8.rs b/core/ops_builtin_v8.rs
index 8629bbdbe..29ba4ec2b 100644
--- a/core/ops_builtin_v8.rs
+++ b/core/ops_builtin_v8.rs
@@ -8,7 +8,6 @@ use crate::ops_builtin::WasmStreamingResource;
 use crate::resolve_url_or_path;
 use crate::serde_v8::from_v8;
 use crate::source_map::apply_source_map as apply_source_map_;
-use crate::JsRealm;
 use crate::JsRuntime;
 use crate::OpDecl;
 use crate::ZeroCopyBuf;
@@ -74,14 +73,14 @@ fn to_v8_local_fn(
 
 #[op(v8)]
 fn op_ref_op(scope: &mut v8::HandleScope, promise_id: i32) {
-  let context_state = JsRealm::state_from_scope(scope);
-  context_state.borrow_mut().unrefed_ops.remove(&promise_id);
+  let state_rc = JsRuntime::state(scope);
+  state_rc.borrow_mut().unrefed_ops.remove(&promise_id);
 }
 
 #[op(v8)]
 fn op_unref_op(scope: &mut v8::HandleScope, promise_id: i32) {
-  let context_state = JsRealm::state_from_scope(scope);
-  context_state.borrow_mut().unrefed_ops.insert(promise_id);
+  let state_rc = JsRuntime::state(scope);
+  state_rc.borrow_mut().unrefed_ops.insert(promise_id);
 }
 
 #[op(v8)]
@@ -112,8 +111,8 @@ fn op_set_promise_reject_callback<'a>(
   cb: serde_v8::Value,
 ) -> Result<Option<serde_v8::Value<'a>>, Error> {
   let cb = to_v8_fn(scope, cb)?;
-  let realm_state_rc = JsRealm::state_from_scope(scope);
-  let old = realm_state_rc.borrow_mut().js_promise_reject_cb.replace(cb);
+  let state_rc = JsRuntime::state(scope);
+  let old = state_rc.borrow_mut().js_promise_reject_cb.replace(cb);
   let old = old.map(|v| v8::Local::new(scope, v));
   Ok(old.map(|v| from_v8(scope, v.into()).unwrap()))
 }
@@ -675,28 +674,22 @@ fn op_set_wasm_streaming_callback(
   cb: serde_v8::Value,
 ) -> Result<(), Error> {
   let cb = to_v8_fn(scope, cb)?;
-  let realm_state_rc = JsRealm::state_from_scope(scope);
-  let mut realm_state = realm_state_rc.borrow_mut();
+  let state_rc = JsRuntime::state(scope);
+  let mut state = state_rc.borrow_mut();
   // The callback to pass to the v8 API has to be a unit type, so it can't
   // borrow or move any local variables. Therefore, we're storing the JS
   // callback in a JsRuntimeState slot.
-  if realm_state.js_wasm_streaming_cb.is_some() {
+  if state.js_wasm_streaming_cb.is_some() {
     return Err(type_error("op_set_wasm_streaming_callback already called"));
   }
-  realm_state.js_wasm_streaming_cb = Some(cb);
+  state.js_wasm_streaming_cb = Some(cb);
 
   scope.set_wasm_streaming_callback(|scope, arg, wasm_streaming| {
     let (cb_handle, streaming_rid) = {
-      let realm_state_rc = JsRealm::state_from_scope(scope);
-      let cb_handle = realm_state_rc
-        .borrow()
-        .js_wasm_streaming_cb
-        .as_ref()
-        .unwrap()
-        .clone();
       let state_rc = JsRuntime::state(scope);
-      let streaming_rid = state_rc
-        .borrow()
+      let state = state_rc.borrow();
+      let cb_handle = state.js_wasm_streaming_cb.as_ref().unwrap().clone();
+      let streaming_rid = state
         .op_state
         .borrow_mut()
         .resource_table
@@ -829,11 +822,8 @@ fn op_set_format_exception_callback<'a>(
   cb: serde_v8::Value<'a>,
 ) -> Result<Option<serde_v8::Value<'a>>, Error> {
   let cb = to_v8_fn(scope, cb)?;
-  let realm_state_rc = JsRealm::state_from_scope(scope);
-  let old = realm_state_rc
-    .borrow_mut()
-    .js_format_exception_cb
-    .replace(cb);
+  let state_rc = JsRuntime::state(scope);
+  let old = state_rc.borrow_mut().js_format_exception_cb.replace(cb);
   let old = old.map(|v| v8::Local::new(scope, v));
   Ok(old.map(|v| from_v8(scope, v.into()).unwrap()))
 }
diff --git a/core/runtime.rs b/core/runtime.rs
index 60e187af5..c1ef6d1a4 100644
--- a/core/runtime.rs
+++ b/core/runtime.rs
@@ -47,8 +47,7 @@ use std::task::Context;
 use std::task::Poll;
 use v8::OwnedIsolate;
 
-type PendingOpFuture =
-  OpCall<(v8::Global<v8::Context>, PromiseId, OpId, OpResult)>;
+type PendingOpFuture = OpCall<(PromiseId, OpId, OpResult)>;
 
 pub enum Snapshot {
   Static(&'static [u8]),
@@ -143,24 +142,18 @@ pub type SharedArrayBufferStore =
 
 pub type CompiledWasmModuleStore = CrossIsolateStore<v8::CompiledWasmModule>;
 
-#[derive(Default)]
-pub(crate) struct ContextState {
-  js_recv_cb: Option<v8::Global<v8::Function>>,
-  pub(crate) js_build_custom_error_cb: Option<v8::Global<v8::Function>>,
-  pub(crate) js_promise_reject_cb: Option<v8::Global<v8::Function>>,
-  pub(crate) js_format_exception_cb: Option<v8::Global<v8::Function>>,
-  pub(crate) js_wasm_streaming_cb: Option<v8::Global<v8::Function>>,
-  pub(crate) unrefed_ops: HashSet<i32>,
-}
-
 /// Internal state for JsRuntime which is stored in one of v8::Isolate's
 /// embedder slots.
 pub(crate) struct JsRuntimeState {
   global_realm: Option<JsRealm>,
-  known_realms: Vec<v8::Weak<v8::Context>>,
+  pub(crate) js_recv_cb: Option<v8::Global<v8::Function>>,
   pub(crate) js_macrotask_cbs: Vec<v8::Global<v8::Function>>,
   pub(crate) js_nexttick_cbs: Vec<v8::Global<v8::Function>>,
+  pub(crate) js_promise_reject_cb: Option<v8::Global<v8::Function>>,
+  pub(crate) js_format_exception_cb: Option<v8::Global<v8::Function>>,
+  pub(crate) js_build_custom_error_cb: Option<v8::Global<v8::Function>>,
   pub(crate) has_tick_scheduled: bool,
+  pub(crate) js_wasm_streaming_cb: Option<v8::Global<v8::Function>>,
   pub(crate) pending_promise_exceptions:
     HashMap<v8::Global<v8::Promise>, v8::Global<v8::Value>>,
   pub(crate) pending_dyn_mod_evaluate: Vec<DynImportModEvaluate>,
@@ -171,6 +164,7 @@ pub(crate) struct JsRuntimeState {
   pub(crate) source_map_getter: Option<Box<dyn SourceMapGetter>>,
   pub(crate) source_map_cache: SourceMapCache,
   pub(crate) pending_ops: FuturesUnordered<PendingOpFuture>,
+  pub(crate) unrefed_ops: HashSet<i32>,
   pub(crate) have_unpolled_ops: bool,
   pub(crate) op_state: Rc<RefCell<OpState>>,
   #[allow(dead_code)]
@@ -408,20 +402,24 @@ impl JsRuntime {
       .module_loader
       .unwrap_or_else(|| Rc::new(NoopModuleLoader));
 
-    let known_realms = vec![v8::Weak::new(&mut isolate, &global_context)];
     let state_rc = Rc::new(RefCell::new(JsRuntimeState {
-      global_realm: Some(JsRealm(global_context.clone())),
-      known_realms,
+      global_realm: Some(JsRealm(global_context)),
       pending_promise_exceptions: HashMap::new(),
       pending_dyn_mod_evaluate: vec![],
       pending_mod_evaluate: None,
       dyn_module_evaluate_idle_counter: 0,
+      js_recv_cb: None,
       js_macrotask_cbs: vec![],
       js_nexttick_cbs: vec![],
+      js_promise_reject_cb: None,
+      js_format_exception_cb: None,
+      js_build_custom_error_cb: None,
       has_tick_scheduled: false,
+      js_wasm_streaming_cb: None,
       source_map_getter: options.source_map_getter,
       source_map_cache: Default::default(),
       pending_ops: FuturesUnordered::new(),
+      unrefed_ops: HashSet::new(),
       shared_array_buffer_store: options.shared_array_buffer_store,
       compiled_wasm_module_store: options.compiled_wasm_module_store,
       op_state: op_state.clone(),
@@ -436,10 +434,6 @@ impl JsRuntime {
       Rc::into_raw(state_rc) as *mut c_void,
     );
 
-    global_context
-      .open(&mut isolate)
-      .set_slot(&mut isolate, Rc::<RefCell<ContextState>>::default());
-
     let module_map_rc = Rc::new(RefCell::new(ModuleMap::new(loader, op_state)));
     isolate.set_data(
       Self::MODULE_MAP_DATA_OFFSET,
@@ -464,8 +458,7 @@ impl JsRuntime {
       js_runtime.init_extension_js(&realm).unwrap();
     }
     // Init callbacks (opresolve)
-    let global_realm = js_runtime.global_realm();
-    js_runtime.init_cbs(&global_realm);
+    js_runtime.init_cbs();
 
     js_runtime
   }
@@ -528,22 +521,12 @@ impl JsRuntime {
         &Self::state(self.v8_isolate()).borrow().op_ctxs,
         self.built_from_snapshot,
       );
-      context.set_slot(scope, Rc::<RefCell<ContextState>>::default());
-
-      Self::state(scope)
-        .borrow_mut()
-        .known_realms
-        .push(v8::Weak::new(scope, &context));
-
       JsRealm::new(v8::Global::new(scope, context))
     };
 
     if !self.built_from_snapshot {
       self.init_extension_js(&realm)?;
     }
-
-    self.init_cbs(&realm);
-
     Ok(realm)
   }
 
@@ -712,24 +695,20 @@ impl JsRuntime {
   }
 
   /// Grabs a reference to core.js' opresolve & syncOpsCache()
-  fn init_cbs(&mut self, realm: &JsRealm) {
-    let (recv_cb, build_custom_error_cb) = {
-      let scope = &mut realm.handle_scope(self.v8_isolate());
-      let recv_cb =
-        Self::grab_global::<v8::Function>(scope, "Deno.core.opresolve")
-          .expect("Deno.core.opresolve is undefined in the realm");
-      let recv_cb = v8::Global::new(scope, recv_cb);
-      let build_custom_error_cb =
-        Self::grab_global::<v8::Function>(scope, "Deno.core.buildCustomError")
-          .expect("Deno.core.buildCustomError is undefined in the realm");
-      let build_custom_error_cb = v8::Global::new(scope, build_custom_error_cb);
-      (recv_cb, build_custom_error_cb)
-    };
-    // Put global handle in callback state
-    let state = realm.state(self.v8_isolate());
-    state.borrow_mut().js_recv_cb.replace(recv_cb);
+  fn init_cbs(&mut self) {
+    let scope = &mut self.handle_scope();
+    let recv_cb =
+      Self::grab_global::<v8::Function>(scope, "Deno.core.opresolve").unwrap();
+    let recv_cb = v8::Global::new(scope, recv_cb);
+    let build_custom_error_cb =
+      Self::grab_global::<v8::Function>(scope, "Deno.core.buildCustomError")
+        .expect("Deno.core.buildCustomError is undefined in the realm");
+    let build_custom_error_cb = v8::Global::new(scope, build_custom_error_cb);
+    // Put global handles in state
+    let state_rc = JsRuntime::state(scope);
+    let mut state = state_rc.borrow_mut();
+    state.js_recv_cb.replace(recv_cb);
     state
-      .borrow_mut()
       .js_build_custom_error_cb
       .replace(build_custom_error_cb);
   }
@@ -794,25 +773,14 @@ impl JsRuntime {
       let v8_isolate = self.v8_isolate();
       Self::drop_state_and_module_map(v8_isolate);
     }
-
     // Drop other v8::Global handles before snapshotting
     {
-      for weak_context in &state.borrow().known_realms {
-        if let Some(context) = weak_context.to_global(self.v8_isolate()) {
-          let realm = JsRealm::new(context.clone());
-          let realm_state = realm.state(self.v8_isolate());
-          std::mem::take(&mut realm_state.borrow_mut().js_recv_cb);
-          std::mem::take(
-            &mut realm_state.borrow_mut().js_build_custom_error_cb,
-          );
-          context
-            .open(self.v8_isolate())
-            .clear_all_slots(self.v8_isolate());
-        }
-      }
       let mut state = state.borrow_mut();
-      state.known_realms.clear();
-      // Free up additional global handles before creating the snapshot
+      std::mem::take(&mut state.js_recv_cb);
+      std::mem::take(&mut state.js_promise_reject_cb);
+      std::mem::take(&mut state.js_format_exception_cb);
+      std::mem::take(&mut state.js_wasm_streaming_cb);
+      std::mem::take(&mut state.js_build_custom_error_cb);
       state.js_macrotask_cbs.clear();
       state.js_nexttick_cbs.clear();
     }
@@ -1125,16 +1093,8 @@ Pending dynamic modules:\n".to_string();
     let state = state_rc.borrow_mut();
     let module_map = module_map_rc.borrow();
 
-    let mut num_unrefed_ops = 0;
-    for weak_context in &state.known_realms {
-      if let Some(context) = weak_context.to_global(isolate) {
-        let realm = JsRealm::new(context);
-        num_unrefed_ops += realm.state(isolate).borrow().unrefed_ops.len();
-      }
-    }
-
     EventLoopPendingState {
-      has_pending_refed_ops: state.pending_ops.len() > num_unrefed_ops,
+      has_pending_refed_ops: state.pending_ops.len() > state.unrefed_ops.len(),
       has_pending_dyn_imports: module_map.has_pending_dynamic_imports(),
       has_pending_dyn_module_evaluation: !state
         .pending_dyn_mod_evaluate
@@ -1903,30 +1863,17 @@ impl JsRuntime {
   fn resolve_async_ops(&mut self, cx: &mut Context) -> Result<(), Error> {
     let state_rc = Self::state(self.v8_isolate());
 
-    // We keep a list of promise IDs and OpResults per realm. Since v8::Context
-    // isn't hashable, `results_per_realm` is a vector of (context, list) tuples
-    type ResultList = Vec<(i32, OpResult)>;
-    let mut results_per_realm: Vec<(v8::Global<v8::Context>, ResultList)> = {
-      let known_realms = &mut state_rc.borrow_mut().known_realms;
-      let mut results = Vec::with_capacity(known_realms.len());
-
-      // Avoid calling the method multiple times
-      let isolate = self.v8_isolate();
-
-      // Remove GC'd realms from `known_realms` at the same time as we populate
-      // `results` with those that are still alive.
-      known_realms.retain(|weak| {
-        if !weak.is_empty() {
-          let context = weak.to_global(isolate).unwrap();
-          results.push((context, vec![]));
-          true
-        } else {
-          false
-        }
-      });
+    let js_recv_cb_handle = state_rc.borrow().js_recv_cb.clone().unwrap();
+    let scope = &mut self.handle_scope();
 
-      results
-    };
+    // We return async responses to JS in unbounded batches (may change),
+    // each batch is a flat vector of tuples:
+    // `[promise_id1, op_result1, promise_id2, op_result2, ...]`
+    // promise_id is a simple integer, op_result is an ops::OpResult
+    // which contains a value OR an error, encoded as a tuple.
+    // This batch is received in JS via the special `arguments` variable
+    // and then each tuple is used to resolve or reject promises
+    let mut args: Vec<v8::Local<v8::Value>> = vec![];
 
     // Now handle actual ops.
     {
@@ -1935,47 +1882,10 @@ impl JsRuntime {
 
       while let Poll::Ready(Some(item)) = state.pending_ops.poll_next_unpin(cx)
       {
-        let (context, promise_id, op_id, resp) = item;
+        let (promise_id, op_id, mut resp) = item;
+        state.unrefed_ops.remove(&promise_id);
         state.op_state.borrow().tracker.track_async_completed(op_id);
-        for (context2, results) in results_per_realm.iter_mut() {
-          if context == *context2 {
-            results.push((promise_id, resp));
-            break;
-          }
-        }
-        JsRealm::new(context)
-          .state(self.v8_isolate())
-          .borrow_mut()
-          .unrefed_ops
-          .remove(&promise_id);
-      }
-    }
-
-    for (context, results) in results_per_realm {
-      if results.is_empty() {
-        continue;
-      }
-
-      let realm = JsRealm::new(context);
-      let js_recv_cb_handle = realm
-        .state(self.v8_isolate())
-        .borrow()
-        .js_recv_cb
-        .clone()
-        .unwrap();
-      let scope = &mut realm.handle_scope(self.v8_isolate());
-
-      // We return async responses to JS in unbounded batches (may change),
-      // each batch is a flat vector of tuples:
-      // `[promise_id1, op_result1, promise_id2, op_result2, ...]`
-      // promise_id is a simple integer, op_result is an ops::OpResult
-      // which contains a value OR an error, encoded as a tuple.
-      // This batch is received in JS via the special `arguments` variable
-      // and then each tuple is used to resolve or reject promises
-      let mut args = vec![];
-
-      for (promise_id, mut resp) in results.into_iter() {
-        args.push(v8::Integer::new(scope, promise_id).into());
+        args.push(v8::Integer::new(scope, promise_id as i32).into());
         args.push(match resp.to_v8(scope) {
           Ok(v) => v,
           Err(e) => OpResult::Err(OpError::new(&|_| "TypeError", e.into()))
@@ -1983,18 +1893,21 @@ impl JsRuntime {
             .unwrap(),
         });
       }
+    }
 
-      let tc_scope = &mut v8::TryCatch::new(scope);
-      let js_recv_cb = js_recv_cb_handle.open(tc_scope);
-      let this = v8::undefined(tc_scope).into();
-      js_recv_cb.call(tc_scope, this, args.as_slice());
-
-      if let Some(exception) = tc_scope.exception() {
-        return exception_to_err_result(tc_scope, exception, false);
-      }
+    if args.is_empty() {
+      return Ok(());
     }
 
-    Ok(())
+    let tc_scope = &mut v8::TryCatch::new(scope);
+    let js_recv_cb = js_recv_cb_handle.open(tc_scope);
+    let this = v8::undefined(tc_scope).into();
+    js_recv_cb.call(tc_scope, this, args.as_slice());
+
+    match tc_scope.exception() {
+      None => Ok(()),
+      Some(exception) => exception_to_err_result(tc_scope, exception, false),
+    }
   }
 
   fn drain_macrotasks(&mut self) -> Result<(), Error> {
@@ -2108,28 +2021,6 @@ impl JsRealm {
     &self.0
   }
 
-  pub(crate) fn state(
-    &self,
-    isolate: &mut v8::Isolate,
-  ) -> Rc<RefCell<ContextState>> {
-    self
-      .context()
-      .open(isolate)
-      .get_slot::<Rc<RefCell<ContextState>>>(isolate)
-      .unwrap()
-      .clone()
-  }
-
-  pub(crate) fn state_from_scope(
-    scope: &mut v8::HandleScope,
-  ) -> Rc<RefCell<ContextState>> {
-    let context = scope.get_current_context();
-    context
-      .get_slot::<Rc<RefCell<ContextState>>>(scope)
-      .unwrap()
-      .clone()
-  }
-
   pub fn handle_scope<'s>(
     &self,
     isolate: &'s mut v8::Isolate,
@@ -2200,8 +2091,7 @@ pub fn queue_async_op(
   state: Rc<RefCell<OpState>>,
   scope: &mut v8::HandleScope,
   deferred: bool,
-  op: impl Future<Output = (v8::Global<v8::Context>, PromiseId, OpId, OpResult)>
-    + 'static,
+  op: impl Future<Output = (PromiseId, OpId, OpResult)> + 'static,
 ) {
   match OpCall::eager(op) {
     // This calls promise.resolve() before the control goes back to userland JS. It works something
@@ -2213,17 +2103,14 @@ pub fn queue_async_op(
     // const p = setPromise();
     // op.op_async(promiseId, ...); // Calls `opresolve`
     // return p;
-    EagerPollResult::Ready((context, promise_id, op_id, mut resp))
-      if !deferred =>
-    {
+    EagerPollResult::Ready((promise_id, op_id, mut resp)) if !deferred => {
       let args = &[
         v8::Integer::new(scope, promise_id).into(),
         resp.to_v8(scope).unwrap(),
       ];
 
-      let realm = JsRealm::new(context);
       let js_recv_cb_handle =
-        realm.state(scope).borrow().js_recv_cb.clone().unwrap();
+        JsRuntime::state(scope).borrow().js_recv_cb.clone().unwrap();
       state.borrow().tracker.track_async_completed(op_id);
 
       let tc_scope = &mut v8::TryCatch::new(scope);
@@ -2361,11 +2248,11 @@ pub mod tests {
       )
       .unwrap();
     {
-      let realm = runtime.global_realm();
       let isolate = runtime.v8_isolate();
       let state_rc = JsRuntime::state(isolate);
-      assert_eq!(state_rc.borrow().pending_ops.len(), 2);
-      assert_eq!(realm.state(isolate).borrow().unrefed_ops.len(), 0);
+      let state = state_rc.borrow();
+      assert_eq!(state.pending_ops.len(), 2);
+      assert_eq!(state.unrefed_ops.len(), 0);
     }
     runtime
       .execute_script(
@@ -2377,11 +2264,11 @@ pub mod tests {
       )
       .unwrap();
     {
-      let realm = runtime.global_realm();
       let isolate = runtime.v8_isolate();
       let state_rc = JsRuntime::state(isolate);
-      assert_eq!(state_rc.borrow().pending_ops.len(), 2);
-      assert_eq!(realm.state(isolate).borrow().unrefed_ops.len(), 2);
+      let state = state_rc.borrow();
+      assert_eq!(state.pending_ops.len(), 2);
+      assert_eq!(state.unrefed_ops.len(), 2);
     }
     runtime
       .execute_script(
@@ -2393,11 +2280,11 @@ pub mod tests {
       )
       .unwrap();
     {
-      let realm = runtime.global_realm();
       let isolate = runtime.v8_isolate();
       let state_rc = JsRuntime::state(isolate);
-      assert_eq!(state_rc.borrow().pending_ops.len(), 2);
-      assert_eq!(realm.state(isolate).borrow().unrefed_ops.len(), 0);
+      let state = state_rc.borrow();
+      assert_eq!(state.pending_ops.len(), 2);
+      assert_eq!(state.unrefed_ops.len(), 0);
     }
   }
 
@@ -3624,54 +3511,6 @@ Deno.core.opAsync('op_async_serialize_object_with_numbers_as_keys', {
   }
 
   #[tokio::test]
-  async fn test_set_promise_reject_callback_realms() {
-    let mut runtime = JsRuntime::new(RuntimeOptions::default());
-    let global_realm = runtime.global_realm();
-    let realm1 = runtime.create_realm().unwrap();
-    let realm2 = runtime.create_realm().unwrap();
-
-    let realm_expectations = &[
-      (&global_realm, "global_realm", 42),
-      (&realm1, "realm1", 140),
-      (&realm2, "realm2", 720),
-    ];
-
-    // Set up promise reject callbacks.
-    for (realm, realm_name, number) in realm_expectations {
-      realm
-        .execute_script(
-          runtime.v8_isolate(),
-          "",
-          &format!(
-            r#"
-              globalThis.rejectValue = undefined;
-              Deno.core.setPromiseRejectCallback((_type, _promise, reason) => {{
-                globalThis.rejectValue = `{realm_name}/${{reason}}`;
-              }});
-              Deno.core.opAsync("op_void_async").then(() => Promise.reject({number}));
-            "#,
-            realm_name=realm_name,
-            number=number
-          ),
-        )
-        .unwrap();
-    }
-
-    runtime.run_event_loop(false).await.unwrap();
-
-    for (realm, realm_name, number) in realm_expectations {
-      let reject_value = realm
-        .execute_script(runtime.v8_isolate(), "", "globalThis.rejectValue")
-        .unwrap();
-      let scope = &mut realm.handle_scope(runtime.v8_isolate());
-      let reject_value = v8::Local::new(scope, reject_value);
-      assert!(reject_value.is_string());
-      let reject_value_string = reject_value.to_rust_string_lossy(scope);
-      assert_eq!(reject_value_string, format!("{}/{}", realm_name, number));
-    }
-  }
-
-  #[tokio::test]
   async fn test_set_promise_reject_callback_top_level_await() {
     static PROMISE_REJECT: AtomicUsize = AtomicUsize::new(0);
 
@@ -3990,180 +3829,4 @@ Deno.core.opAsync('op_async_serialize_object_with_numbers_as_keys', {
     let scope = &mut realm.handle_scope(runtime.v8_isolate());
     assert_eq!(ret, serde_v8::to_v8(scope, "Test").unwrap());
   }
-
-  #[test]
-  fn js_realm_sync_ops() {
-    // Test that returning a ZeroCopyBuf and throwing an exception from a sync
-    // op result in objects with prototypes from the right realm. Note that we
-    // don't test the result of returning structs, because they will be
-    // serialized to objects with null prototype.
-
-    #[op]
-    fn op_test(fail: bool) -> Result<ZeroCopyBuf, Error> {
-      if !fail {
-        Ok(ZeroCopyBuf::empty())
-      } else {
-        Err(crate::error::type_error("Test"))
-      }
-    }
-
-    let mut runtime = JsRuntime::new(RuntimeOptions {
-      extensions: vec![Extension::builder().ops(vec![op_test::decl()]).build()],
-      get_error_class_fn: Some(&|error| {
-        crate::error::get_custom_error_class(error).unwrap()
-      }),
-      ..Default::default()
-    });
-    let new_realm = runtime.create_realm().unwrap();
-
-    // Test in both realms
-    for realm in [runtime.global_realm(), new_realm].into_iter() {
-      let ret = realm
-        .execute_script(
-          runtime.v8_isolate(),
-          "",
-          r#"
-            const buf = Deno.core.ops.op_test(false);
-            let err;
-            try {
-              Deno.core.ops.op_test(true);
-            } catch(e) {
-              err = e;
-            }
-            buf instanceof Uint8Array && buf.byteLength === 0 &&
-            err instanceof TypeError && err.message === "Test"
-          "#,
-        )
-        .unwrap();
-      assert!(ret.open(runtime.v8_isolate()).is_true());
-    }
-  }
-
-  #[tokio::test]
-  async fn js_realm_async_ops() {
-    // Test that returning a ZeroCopyBuf and throwing an exception from a async
-    // op result in objects with prototypes from the right realm. Note that we
-    // don't test the result of returning structs, because they will be
-    // serialized to objects with null prototype.
-
-    #[op]
-    async fn op_test(fail: bool) -> Result<ZeroCopyBuf, Error> {
-      if !fail {
-        Ok(ZeroCopyBuf::empty())
-      } else {
-        Err(crate::error::type_error("Test"))
-      }
-    }
-
-    let mut runtime = JsRuntime::new(RuntimeOptions {
-      extensions: vec![Extension::builder().ops(vec![op_test::decl()]).build()],
-      get_error_class_fn: Some(&|error| {
-        crate::error::get_custom_error_class(error).unwrap()
-      }),
-      ..Default::default()
-    });
-
-    let global_realm = runtime.global_realm();
-    let new_realm = runtime.create_realm().unwrap();
-
-    let mut rets = vec![];
-
-    // Test in both realms
-    for realm in [global_realm, new_realm].into_iter() {
-      let ret = realm
-        .execute_script(
-          runtime.v8_isolate(),
-          "",
-          r#"
-              (async function () {
-                const buf = await Deno.core.opAsync("op_test", false);
-                let err;
-                try {
-                  await Deno.core.opAsync("op_test", true);
-                } catch(e) {
-                  err = e;
-                }
-                return buf instanceof Uint8Array && buf.byteLength === 0 &&
-                       err instanceof TypeError && err.message === "Test" ;
-              })();
-            "#,
-        )
-        .unwrap();
-      rets.push((realm, ret));
-    }
-
-    runtime.run_event_loop(false).await.unwrap();
-
-    for ret in rets {
-      let scope = &mut ret.0.handle_scope(runtime.v8_isolate());
-      let value = v8::Local::new(scope, ret.1);
-      let promise = v8::Local::<v8::Promise>::try_from(value).unwrap();
-      let result = promise.result(scope);
-
-      assert!(result.is_boolean() && result.is_true());
-    }
-  }
-
-  #[tokio::test]
-  async fn js_realm_ref_unref_ops() {
-    run_in_task(|cx| {
-      // Never resolves.
-      #[op]
-      async fn op_pending() {
-        futures::future::pending().await
-      }
-
-      let mut runtime = JsRuntime::new(RuntimeOptions {
-        extensions: vec![Extension::builder()
-          .ops(vec![op_pending::decl()])
-          .build()],
-        ..Default::default()
-      });
-      let main_realm = runtime.global_realm();
-      let other_realm = runtime.create_realm().unwrap();
-
-      main_realm
-        .execute_script(
-          runtime.v8_isolate(),
-          "",
-          "var promise = Deno.core.opAsync('op_pending');",
-        )
-        .unwrap();
-      other_realm
-        .execute_script(
-          runtime.v8_isolate(),
-          "",
-          "var promise = Deno.core.opAsync('op_pending');",
-        )
-        .unwrap();
-      assert!(matches!(runtime.poll_event_loop(cx, false), Poll::Pending));
-
-      main_realm
-        .execute_script(
-          runtime.v8_isolate(),
-          "",
-          r#"
-        let promiseIdSymbol = Symbol.for("Deno.core.internalPromiseId");
-        Deno.core.ops.op_unref_op(promise[promiseIdSymbol]);
-      "#,
-        )
-        .unwrap();
-      assert!(matches!(runtime.poll_event_loop(cx, false), Poll::Pending));
-
-      other_realm
-        .execute_script(
-          runtime.v8_isolate(),
-          "",
-          r#"
-        let promiseIdSymbol = Symbol.for("Deno.core.internalPromiseId");
-        Deno.core.ops.op_unref_op(promise[promiseIdSymbol]);
-      "#,
-        )
-        .unwrap();
-      assert!(matches!(
-        runtime.poll_event_loop(cx, false),
-        Poll::Ready(Ok(()))
-      ));
-    });
-  }
 }
diff --git a/ops/lib.rs b/ops/lib.rs
index e8ea1e969..0794bdf33 100644
--- a/ops/lib.rs
+++ b/ops/lib.rs
@@ -215,7 +215,7 @@ fn codegen_v8_async(
         quote! {
           let result = match result {
             Ok(fut) => fut.await,
-            Err(e) => return (context, promise_id, op_id, #core::_ops::to_op_result::<()>(get_class, Err(e))),
+            Err(e) => return (promise_id, op_id, #core::_ops::to_op_result::<()>(get_class, Err(e))),
           };
         }
       } else {
@@ -258,16 +258,11 @@ fn codegen_v8_async(
       state.get_error_class_fn
     };
 
-    let context = {
-      let local = scope.get_current_context();
-      #core::v8::Global::new(scope, local)
-    };
-
     #pre_result
     #core::_ops::queue_async_op(state, scope, #deferred, async move {
       let result = #result_fut
       #result_wrapper
-      (context, promise_id, op_id, #core::_ops::to_op_result(get_class, result))
+      (promise_id, op_id, #core::_ops::to_op_result(get_class, result))
     });
   }
 }