// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license. use crate::bindings::script_origin; use crate::error::is_instance_of_error; use crate::error::range_error; use crate::error::type_error; use crate::error::JsError; 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; use anyhow::Error; use deno_ops::op; use serde::Deserialize; use serde::Serialize; use std::cell::RefCell; use v8::ValueDeserializerHelper; use v8::ValueSerializerHelper; pub(crate) fn init_builtins_v8() -> Vec { vec![ op_ref_op::decl(), op_unref_op::decl(), op_set_macrotask_callback::decl(), op_set_next_tick_callback::decl(), op_set_promise_reject_callback::decl(), op_run_microtasks::decl(), op_has_tick_scheduled::decl(), op_set_has_tick_scheduled::decl(), op_eval_context::decl(), op_queue_microtask::decl(), op_create_host_object::decl(), op_encode::decl(), op_decode::decl(), op_serialize::decl(), op_deserialize::decl(), op_set_promise_hooks::decl(), op_get_promise_details::decl(), op_get_proxy_details::decl(), op_memory_usage::decl(), op_set_wasm_streaming_callback::decl(), op_abort_wasm_streaming::decl(), op_destructure_error::decl(), op_dispatch_exception::decl(), op_op_names::decl(), 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(), ] } fn to_v8_fn( scope: &mut v8::HandleScope, value: serde_v8::Value, ) -> Result, Error> { v8::Local::::try_from(value.v8_value) .map(|cb| v8::Global::new(scope, cb)) .map_err(|err| type_error(err.to_string())) } #[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); } #[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); } #[op(v8)] fn op_set_macrotask_callback( scope: &mut v8::HandleScope, cb: serde_v8::Value, ) -> Result<(), Error> { let cb = to_v8_fn(scope, cb)?; let state_rc = JsRuntime::state(scope); state_rc.borrow_mut().js_macrotask_cbs.push(cb); Ok(()) } #[op(v8)] fn op_set_next_tick_callback( scope: &mut v8::HandleScope, cb: serde_v8::Value, ) -> Result<(), Error> { let cb = to_v8_fn(scope, cb)?; let state_rc = JsRuntime::state(scope); state_rc.borrow_mut().js_nexttick_cbs.push(cb); Ok(()) } #[op(v8)] fn op_set_promise_reject_callback<'a>( scope: &mut v8::HandleScope<'a>, cb: serde_v8::Value, ) -> Result>, 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 old = old.map(|v| v8::Local::new(scope, v)); Ok(old.map(|v| from_v8(scope, v.into()).unwrap())) } #[op(v8)] fn op_run_microtasks(scope: &mut v8::HandleScope) { scope.perform_microtask_checkpoint(); } #[op(v8)] fn op_has_tick_scheduled(scope: &mut v8::HandleScope) -> bool { let state_rc = JsRuntime::state(scope); let state = state_rc.borrow(); state.has_tick_scheduled } #[op(v8)] fn op_set_has_tick_scheduled(scope: &mut v8::HandleScope, v: bool) { let state_rc = JsRuntime::state(scope); state_rc.borrow_mut().has_tick_scheduled = v; } #[derive(Serialize)] #[serde(rename_all = "camelCase")] struct EvalContextError<'s> { thrown: serde_v8::Value<'s>, is_native_error: bool, is_compile_error: bool, } #[derive(Serialize)] struct EvalContextResult<'s>( Option>, Option>, ); #[op(v8)] fn op_eval_context<'a>( scope: &mut v8::HandleScope<'a>, source: serde_v8::Value<'a>, specifier: Option, ) -> Result, Error> { let tc_scope = &mut v8::TryCatch::new(scope); let source = v8::Local::::try_from(source.v8_value) .map_err(|_| type_error("Invalid source"))?; let specifier = match specifier { Some(s) => resolve_url_or_path(&s)?.to_string(), None => crate::DUMMY_SPECIFIER.to_string(), }; let specifier = v8::String::new(tc_scope, &specifier).unwrap(); let origin = script_origin(tc_scope, specifier); let script = match v8::Script::compile(tc_scope, source, Some(&origin)) { Some(s) => s, None => { assert!(tc_scope.has_caught()); let exception = tc_scope.exception().unwrap(); return Ok(EvalContextResult( None, Some(EvalContextError { thrown: exception.into(), is_native_error: is_instance_of_error(tc_scope, exception), is_compile_error: true, }), )); } }; match script.run(tc_scope) { Some(result) => Ok(EvalContextResult(Some(result.into()), None)), None => { assert!(tc_scope.has_caught()); let exception = tc_scope.exception().unwrap(); Ok(EvalContextResult( None, Some(EvalContextError { thrown: exception.into(), is_native_error: is_instance_of_error(tc_scope, exception), is_compile_error: false, }), )) } } } #[op(v8)] fn op_queue_microtask( scope: &mut v8::HandleScope, cb: serde_v8::Value, ) -> Result<(), Error> { let cb = to_v8_fn(scope, cb)?; let cb = v8::Local::new(scope, cb); scope.enqueue_microtask(cb); Ok(()) } #[op(v8)] fn op_create_host_object<'a>( scope: &mut v8::HandleScope<'a>, ) -> serde_v8::Value<'a> { let template = v8::ObjectTemplate::new(scope); template.set_internal_field_count(1); let object = template.new_instance(scope).unwrap(); from_v8(scope, object.into()).unwrap() } #[op(v8)] fn op_encode<'a>( scope: &mut v8::HandleScope<'a>, text: serde_v8::Value<'a>, ) -> Result, Error> { let text = v8::Local::::try_from(text.v8_value) .map_err(|_| type_error("Invalid argument"))?; let text_str = serde_v8::to_utf8(text, scope); let bytes = text_str.into_bytes(); let len = bytes.len(); let backing_store = v8::ArrayBuffer::new_backing_store_from_vec(bytes).make_shared(); let buffer = v8::ArrayBuffer::with_backing_store(scope, &backing_store); let u8array = v8::Uint8Array::new(scope, buffer, 0, len).unwrap(); Ok((from_v8(scope, u8array.into()))?) } #[op(v8)] fn op_decode<'a>( scope: &mut v8::HandleScope<'a>, zero_copy: &[u8], ) -> Result, Error> { let buf = &zero_copy; // Strip BOM let buf = if buf.len() >= 3 && buf[0] == 0xef && buf[1] == 0xbb && buf[2] == 0xbf { &buf[3..] } else { buf }; // If `String::new_from_utf8()` returns `None`, this means that the // length of the decoded string would be longer than what V8 can // handle. In this case we return `RangeError`. // // For more details see: // - https://encoding.spec.whatwg.org/#dom-textdecoder-decode // - https://github.com/denoland/deno/issues/6649 // - https://github.com/v8/v8/blob/d68fb4733e39525f9ff0a9222107c02c28096e2a/include/v8.h#L3277-L3278 match v8::String::new_from_utf8(scope, buf, v8::NewStringType::Normal) { Some(text) => Ok(from_v8(scope, text.into())?), None => Err(range_error("string too long")), } } struct SerializeDeserialize<'a> { host_objects: Option>, error_callback: Option>, } impl<'a> v8::ValueSerializerImpl for SerializeDeserialize<'a> { #[allow(unused_variables)] fn throw_data_clone_error<'s>( &mut self, scope: &mut v8::HandleScope<'s>, message: v8::Local<'s, v8::String>, ) { if let Some(cb) = self.error_callback { let scope = &mut v8::TryCatch::new(scope); let undefined = v8::undefined(scope).into(); cb.call(scope, undefined, &[message.into()]); if scope.has_caught() || scope.has_terminated() { scope.rethrow(); return; }; } let error = v8::Exception::type_error(scope, message); scope.throw_exception(error); } fn get_shared_array_buffer_id<'s>( &mut self, scope: &mut v8::HandleScope<'s>, shared_array_buffer: v8::Local<'s, v8::SharedArrayBuffer>, ) -> Option { let state_rc = JsRuntime::state(scope); let state = state_rc.borrow_mut(); if let Some(shared_array_buffer_store) = &state.shared_array_buffer_store { let backing_store = shared_array_buffer.get_backing_store(); let id = shared_array_buffer_store.insert(backing_store); Some(id) } else { None } } fn get_wasm_module_transfer_id( &mut self, scope: &mut v8::HandleScope<'_>, module: v8::Local, ) -> Option { let state_rc = JsRuntime::state(scope); let state = state_rc.borrow_mut(); if let Some(compiled_wasm_module_store) = &state.compiled_wasm_module_store { let compiled_wasm_module = module.get_compiled_module(); let id = compiled_wasm_module_store.insert(compiled_wasm_module); Some(id) } else { None } } fn write_host_object<'s>( &mut self, scope: &mut v8::HandleScope<'s>, object: v8::Local<'s, v8::Object>, value_serializer: &mut dyn v8::ValueSerializerHelper, ) -> Option { if let Some(host_objects) = self.host_objects { for i in 0..host_objects.length() { let value = host_objects.get_index(scope, i).unwrap(); if value == object { value_serializer.write_uint32(i); return Some(true); } } } let message = v8::String::new(scope, "Unsupported object type").unwrap(); self.throw_data_clone_error(scope, message); None } } impl<'a> v8::ValueDeserializerImpl for SerializeDeserialize<'a> { fn get_shared_array_buffer_from_id<'s>( &mut self, scope: &mut v8::HandleScope<'s>, transfer_id: u32, ) -> Option> { let state_rc = JsRuntime::state(scope); let state = state_rc.borrow_mut(); if let Some(shared_array_buffer_store) = &state.shared_array_buffer_store { let backing_store = shared_array_buffer_store.take(transfer_id)?; let shared_array_buffer = v8::SharedArrayBuffer::with_backing_store(scope, &backing_store); Some(shared_array_buffer) } else { None } } fn get_wasm_module_from_id<'s>( &mut self, scope: &mut v8::HandleScope<'s>, clone_id: u32, ) -> Option> { let state_rc = JsRuntime::state(scope); let state = state_rc.borrow_mut(); if let Some(compiled_wasm_module_store) = &state.compiled_wasm_module_store { let compiled_module = compiled_wasm_module_store.take(clone_id)?; v8::WasmModuleObject::from_compiled_module(scope, &compiled_module) } else { None } } fn read_host_object<'s>( &mut self, scope: &mut v8::HandleScope<'s>, value_deserializer: &mut dyn v8::ValueDeserializerHelper, ) -> Option> { if let Some(host_objects) = self.host_objects { let mut i = 0; if !value_deserializer.read_uint32(&mut i) { return None; } let maybe_value = host_objects.get_index(scope, i); if let Some(value) = maybe_value { return value.to_object(scope); } } let message = v8::String::new(scope, "Failed to deserialize host object").unwrap(); let error = v8::Exception::error(scope, message); scope.throw_exception(error); None } } #[derive(Default, Deserialize)] #[serde(rename_all = "camelCase")] struct SerializeDeserializeOptions<'a> { host_objects: Option>, transferred_array_buffers: Option>, } #[op(v8)] fn op_serialize( scope: &mut v8::HandleScope, value: serde_v8::Value, options: Option, error_callback: Option, ) -> Result { let options = options.unwrap_or_default(); let error_callback = match error_callback { Some(cb) => Some( v8::Local::::try_from(cb.v8_value) .map_err(|_| type_error("Invalid error callback"))?, ), None => None, }; let host_objects = match options.host_objects { Some(value) => Some( v8::Local::::try_from(value.v8_value) .map_err(|_| type_error("hostObjects not an array"))?, ), None => None, }; let transferred_array_buffers = match options.transferred_array_buffers { Some(value) => Some( v8::Local::::try_from(value.v8_value) .map_err(|_| type_error("transferredArrayBuffers not an array"))?, ), None => None, }; let serialize_deserialize = Box::new(SerializeDeserialize { host_objects, error_callback, }); let mut value_serializer = v8::ValueSerializer::new(scope, serialize_deserialize); value_serializer.write_header(); if let Some(transferred_array_buffers) = transferred_array_buffers { let state_rc = JsRuntime::state(scope); let state = state_rc.borrow_mut(); for i in 0..transferred_array_buffers.length() { let i = v8::Number::new(scope, i as f64).into(); let buf = transferred_array_buffers.get(scope, i).unwrap(); let buf = v8::Local::::try_from(buf).map_err(|_| { type_error("item in transferredArrayBuffers not an ArrayBuffer") })?; if let Some(shared_array_buffer_store) = &state.shared_array_buffer_store { // TODO(lucacasonato): we need to check here that the buffer is not // already detached. We can not do that because V8 does not provide // a way to check if a buffer is already detached. if !buf.is_detachable() { return Err(type_error( "item in transferredArrayBuffers is not transferable", )); } let backing_store = buf.get_backing_store(); buf.detach(); let id = shared_array_buffer_store.insert(backing_store); value_serializer.transfer_array_buffer(id, buf); let id = v8::Number::new(scope, id as f64).into(); transferred_array_buffers.set(scope, i, id); } } } let scope = &mut v8::TryCatch::new(scope); let ret = value_serializer.write_value(scope.get_current_context(), value.v8_value); if scope.has_caught() || scope.has_terminated() { scope.rethrow(); // Dummy value, this result will be discarded because an error was thrown. Ok(ZeroCopyBuf::empty()) } else if let Some(true) = ret { let vector = value_serializer.release(); Ok(vector.into()) } else { Err(type_error("Failed to serialize response")) } } #[op(v8)] fn op_deserialize<'a>( scope: &mut v8::HandleScope<'a>, zero_copy: ZeroCopyBuf, options: Option, ) -> Result, Error> { let options = options.unwrap_or_default(); let host_objects = match options.host_objects { Some(value) => Some( v8::Local::::try_from(value.v8_value) .map_err(|_| type_error("hostObjects not an array"))?, ), None => None, }; let transferred_array_buffers = match options.transferred_array_buffers { Some(value) => Some( v8::Local::::try_from(value.v8_value) .map_err(|_| type_error("transferredArrayBuffers not an array"))?, ), None => None, }; let serialize_deserialize = Box::new(SerializeDeserialize { host_objects, error_callback: None, }); let mut value_deserializer = v8::ValueDeserializer::new(scope, serialize_deserialize, &zero_copy); let parsed_header = value_deserializer .read_header(scope.get_current_context()) .unwrap_or_default(); if !parsed_header { return Err(range_error("could not deserialize value")); } if let Some(transferred_array_buffers) = transferred_array_buffers { let state_rc = JsRuntime::state(scope); let state = state_rc.borrow_mut(); if let Some(shared_array_buffer_store) = &state.shared_array_buffer_store { for i in 0..transferred_array_buffers.length() { let i = v8::Number::new(scope, i as f64).into(); let id_val = transferred_array_buffers.get(scope, i).unwrap(); let id = match id_val.number_value(scope) { Some(id) => id as u32, None => { return Err(type_error( "item in transferredArrayBuffers not number", )) } }; if let Some(backing_store) = shared_array_buffer_store.take(id) { let array_buffer = v8::ArrayBuffer::with_backing_store(scope, &backing_store); value_deserializer.transfer_array_buffer(id, array_buffer); transferred_array_buffers.set(scope, id_val, array_buffer.into()); } else { return Err(type_error( "transferred array buffer not present in shared_array_buffer_store", )); } } } } let value = value_deserializer.read_value(scope.get_current_context()); match value { Some(deserialized) => Ok(deserialized.into()), None => Err(range_error("could not deserialize value")), } } #[derive(Serialize)] struct PromiseDetails<'s>(u32, Option>); #[op(v8)] fn op_get_promise_details<'a>( scope: &mut v8::HandleScope<'a>, promise: serde_v8::Value<'a>, ) -> Result, Error> { let promise = v8::Local::::try_from(promise.v8_value) .map_err(|_| type_error("Invalid argument"))?; match promise.state() { v8::PromiseState::Pending => Ok(PromiseDetails(0, None)), v8::PromiseState::Fulfilled => { Ok(PromiseDetails(1, Some(promise.result(scope).into()))) } v8::PromiseState::Rejected => { Ok(PromiseDetails(2, Some(promise.result(scope).into()))) } } } #[op(v8)] fn op_set_promise_hooks<'a>( scope: &mut v8::HandleScope<'a>, init_cb: serde_v8::Value, before_cb: serde_v8::Value, after_cb: serde_v8::Value, resolve_cb: serde_v8::Value, ) -> Result<(), Error> { let init_hook_global = to_v8_fn(scope, init_cb)?; let before_hook_global = to_v8_fn(scope, before_cb)?; let after_hook_global = to_v8_fn(scope, after_cb)?; let resolve_hook_global = to_v8_fn(scope, resolve_cb)?; let init_hook = v8::Local::new(scope, init_hook_global); let before_hook = v8::Local::new(scope, before_hook_global); let after_hook = v8::Local::new(scope, after_hook_global); let resolve_hook = v8::Local::new(scope, resolve_hook_global); scope.get_current_context().set_promise_hooks( init_hook, before_hook, after_hook, resolve_hook, ); Ok(()) } // Based on https://github.com/nodejs/node/blob/1e470510ff74391d7d4ec382909ea8960d2d2fbc/src/node_util.cc // Copyright Joyent, Inc. and other Node contributors. // // Permission is hereby granted, free of charge, to any person obtaining a // copy of this software and associated documentation files (the // "Software"), to deal in the Software without restriction, including // without limitation the rights to use, copy, modify, merge, publish, // distribute, sublicense, and/or sell copies of the Software, and to permit // persons to whom the Software is furnished to do so, subject to the // following conditions: // // The above copyright notice and this permission notice shall be included // in all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN // NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, // DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE // USE OR OTHER DEALINGS IN THE SOFTWARE. #[op(v8)] fn op_get_proxy_details<'a>( scope: &mut v8::HandleScope<'a>, proxy: serde_v8::Value<'a>, ) -> Option<(serde_v8::Value<'a>, serde_v8::Value<'a>)> { let proxy = match v8::Local::::try_from(proxy.v8_value) { Ok(proxy) => proxy, Err(_) => return None, }; let target = proxy.get_target(scope); let handler = proxy.get_handler(scope); Some((target.into(), handler.into())) } // HeapStats stores values from a isolate.get_heap_statistics() call #[derive(Serialize)] #[serde(rename_all = "camelCase")] struct MemoryUsage { rss: usize, heap_total: usize, heap_used: usize, external: usize, // TODO: track ArrayBuffers, would require using a custom allocator to track // but it's otherwise a subset of external so can be indirectly tracked // array_buffers: usize, } #[op(v8)] fn op_memory_usage(scope: &mut v8::HandleScope) -> MemoryUsage { let mut s = v8::HeapStatistics::default(); scope.get_heap_statistics(&mut s); MemoryUsage { rss: s.total_physical_size(), heap_total: s.total_heap_size(), heap_used: s.used_heap_size(), external: s.external_memory(), } } #[op(v8)] fn op_set_wasm_streaming_callback( scope: &mut v8::HandleScope, 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(); // 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() { return Err(type_error("op_set_wasm_streaming_callback already called")); } realm_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() .op_state .borrow_mut() .resource_table .add(WasmStreamingResource(RefCell::new(wasm_streaming))); (cb_handle, streaming_rid) }; let undefined = v8::undefined(scope); let rid = serde_v8::to_v8(scope, streaming_rid).unwrap(); cb_handle .open(scope) .call(scope, undefined.into(), &[arg, rid]); }); Ok(()) } #[allow(clippy::let_and_return)] #[op(v8)] fn op_abort_wasm_streaming( scope: &mut v8::HandleScope, rid: u32, error: serde_v8::Value, ) -> Result<(), Error> { let wasm_streaming = { let state_rc = JsRuntime::state(scope); let state = state_rc.borrow(); let wsr = state .op_state .borrow_mut() .resource_table .take::(rid)?; wsr }; // At this point there are no clones of Rc on the // resource table, and no one should own a reference because we're never // cloning them. So we can be sure `wasm_streaming` is the only reference. if let Ok(wsr) = std::rc::Rc::try_unwrap(wasm_streaming) { // NOTE: v8::WasmStreaming::abort can't be called while `state` is borrowed; // see https://github.com/denoland/deno/issues/13917 wsr.0.into_inner().abort(Some(error.v8_value)); } else { panic!("Couldn't consume WasmStreamingResource."); } Ok(()) } #[op(v8)] fn op_destructure_error( scope: &mut v8::HandleScope, error: serde_v8::Value, ) -> JsError { JsError::from_v8_exception(scope, error.v8_value) } /// Effectively throw an uncatchable error. This will terminate runtime /// execution before any more JS code can run, except in the REPL where it /// should just output the error to the console. #[op(v8)] fn op_dispatch_exception( scope: &mut v8::HandleScope, exception: serde_v8::Value, ) { let state_rc = JsRuntime::state(scope); let mut state = state_rc.borrow_mut(); state .dispatched_exceptions .push_front(v8::Global::new(scope, exception.v8_value)); // Only terminate execution if there are no inspector sessions. match state.inspector().try_borrow() { Ok(inspector) if !inspector.has_active_sessions() => { scope.terminate_execution(); } // If the inspector is borrowed at this time, assume an inspector is active. _ => {} } } #[op(v8)] fn op_op_names(scope: &mut v8::HandleScope) -> Vec { let state_rc = JsRuntime::state(scope); let state = state_rc.borrow(); state .op_ctxs .iter() .map(|o| o.decl.name.to_string()) .collect() } #[derive(Deserialize, Serialize)] #[serde(rename_all = "camelCase")] struct Location { file_name: String, line_number: u32, column_number: u32, } #[op(v8)] fn op_apply_source_map( scope: &mut v8::HandleScope, location: Location, ) -> Result { let state_rc = JsRuntime::state(scope); let state = &mut *state_rc.borrow_mut(); if let Some(source_map_getter) = &state.source_map_getter { let mut location = location; let (f, l, c) = apply_source_map_( location.file_name, location.line_number.into(), location.column_number.into(), &mut state.source_map_cache, source_map_getter.as_ref(), ); location.file_name = f; location.line_number = l as u32; location.column_number = c as u32; Ok(location) } else { Ok(location) } } /// Set a callback which formats exception messages as stored in /// `JsError::exception_message`. The callback is passed the error value and /// should return a string or `null`. If no callback is set or the callback /// returns `null`, the built-in default formatting will be used. #[op(v8)] fn op_set_format_exception_callback<'a>( scope: &mut v8::HandleScope<'a>, cb: serde_v8::Value<'a>, ) -> Result>, 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 old = old.map(|v| v8::Local::new(scope, v)); Ok(old.map(|v| from_v8(scope, v.into()).unwrap())) } #[op(v8)] 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::::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::::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::::try_from(promise.v8_value).unwrap(); let promise_global = v8::Global::new(scope, promise_value); state .pending_promise_exceptions .contains_key(&promise_global) }