From 4fb948d8e7576e30c348aba298d4d3d65d394183 Mon Sep 17 00:00:00 2001 From: Timothy Flynn Date: Wed, 20 Oct 2021 22:35:43 -0400 Subject: [PATCH] LibJS: Convert IfAbruptRejectPromise AO to a GNU statement expression GNU statement expressions fit the definition of IfAbruptRejectPromise rather nicely, where we need to reject the failed promise (and return the failed promise itself) on failure, and otherwise store a value on success. --- .../LibJS/Runtime/PromiseConstructor.cpp | 95 +++++-------------- 1 file changed, 24 insertions(+), 71 deletions(-) diff --git a/Userland/Libraries/LibJS/Runtime/PromiseConstructor.cpp b/Userland/Libraries/LibJS/Runtime/PromiseConstructor.cpp index 58374d8c4f..a0e3c5c0f9 100644 --- a/Userland/Libraries/LibJS/Runtime/PromiseConstructor.cpp +++ b/Userland/Libraries/LibJS/Runtime/PromiseConstructor.cpp @@ -35,33 +35,18 @@ static ThrowCompletionOr get_promise_resolve(GlobalObject& global_object, } // 27.2.1.1.1 IfAbruptRejectPromise ( value, capability ), https://tc39.es/ecma262/#sec-ifabruptrejectpromise -template -static Optional if_abrupt_reject_promise(GlobalObject& global_object, ValueType const& value_or_error, PromiseCapability capability) -{ - auto& vm = global_object.vm(); - - // FIXME: This is temporary multi-type support. When all callers to this method are transformed - // to use ThrowCompletionOr, the 'else' clause (and template) can be dropped. - if constexpr (requires { value_or_error.is_throw_completion(); }) { - if (value_or_error.is_throw_completion()) { - vm.clear_exception(); - vm.stop_unwind(); - - (void)vm.call(*capability.reject, js_undefined(), value_or_error.throw_completion().value()); - return capability.promise; - } - } else { - if (auto* exception = vm.exception()) { - vm.clear_exception(); - vm.stop_unwind(); - - (void)vm.call(*capability.reject, js_undefined(), exception->value()); - return capability.promise; - } - } - - return {}; -} +#define TRY_OR_REJECT(vm, capability, expression) \ + ({ \ + auto _temporary_result = (expression); \ + if (_temporary_result.is_error()) { \ + vm.clear_exception(); \ + vm.stop_unwind(); \ + \ + (void)vm.call(*capability.reject, js_undefined(), _temporary_result.release_error().value()); \ + return capability.promise; \ + } \ + _temporary_result.release_value(); \ + }) static bool iterator_record_is_complete(GlobalObject& global_object, Object& iterator_record) { @@ -287,15 +272,8 @@ JS_DEFINE_OLD_NATIVE_FUNCTION(PromiseConstructor::all) if (vm.exception()) return {}; - auto promise_resolve_or_error = get_promise_resolve(global_object, constructor); - if (auto abrupt = if_abrupt_reject_promise(global_object, promise_resolve_or_error, promise_capability); abrupt.has_value()) - return abrupt.value(); - auto promise_resolve = promise_resolve_or_error.release_value(); - - auto iterator_record_or_error = get_iterator(global_object, vm.argument(0)); - if (auto abrupt = if_abrupt_reject_promise(global_object, iterator_record_or_error, promise_capability); abrupt.has_value()) - return abrupt.value(); - auto* iterator_record = iterator_record_or_error.release_value(); + auto promise_resolve = TRY_OR_REJECT(vm, promise_capability, get_promise_resolve(global_object, constructor)); + auto* iterator_record = TRY_OR_REJECT(vm, promise_capability, get_iterator(global_object, vm.argument(0))); auto result = perform_promise_all(global_object, *iterator_record, constructor, promise_capability, promise_resolve); if (auto* exception = vm.exception()) { @@ -307,8 +285,7 @@ JS_DEFINE_OLD_NATIVE_FUNCTION(PromiseConstructor::all) result_error = iterator_close(*iterator_record, move(result_error)); } - auto abrupt = if_abrupt_reject_promise(global_object, result_error, promise_capability); - return abrupt.value(); + TRY_OR_REJECT(vm, promise_capability, result_error); } return result; @@ -323,15 +300,8 @@ JS_DEFINE_OLD_NATIVE_FUNCTION(PromiseConstructor::all_settled) if (vm.exception()) return {}; - auto promise_resolve_or_error = get_promise_resolve(global_object, constructor); - if (auto abrupt = if_abrupt_reject_promise(global_object, promise_resolve_or_error, promise_capability); abrupt.has_value()) - return abrupt.value(); - auto promise_resolve = promise_resolve_or_error.release_value(); - - auto iterator_record_or_error = get_iterator(global_object, vm.argument(0)); - if (auto abrupt = if_abrupt_reject_promise(global_object, iterator_record_or_error, promise_capability); abrupt.has_value()) - return abrupt.value(); - auto* iterator_record = iterator_record_or_error.release_value(); + auto promise_resolve = TRY_OR_REJECT(vm, promise_capability, get_promise_resolve(global_object, constructor)); + auto* iterator_record = TRY_OR_REJECT(vm, promise_capability, get_iterator(global_object, vm.argument(0))); auto result = perform_promise_all_settled(global_object, *iterator_record, constructor, promise_capability, promise_resolve); if (auto* exception = vm.exception()) { @@ -343,8 +313,7 @@ JS_DEFINE_OLD_NATIVE_FUNCTION(PromiseConstructor::all_settled) result_error = iterator_close(*iterator_record, move(result_error)); } - auto abrupt = if_abrupt_reject_promise(global_object, result_error, promise_capability); - return abrupt.value(); + TRY_OR_REJECT(vm, promise_capability, result_error); } return result; @@ -359,15 +328,8 @@ JS_DEFINE_OLD_NATIVE_FUNCTION(PromiseConstructor::any) if (vm.exception()) return {}; - auto promise_resolve_or_error = get_promise_resolve(global_object, constructor); - if (auto abrupt = if_abrupt_reject_promise(global_object, promise_resolve_or_error, promise_capability); abrupt.has_value()) - return abrupt.value(); - auto promise_resolve = promise_resolve_or_error.release_value(); - - auto iterator_record_or_error = get_iterator(global_object, vm.argument(0)); - if (auto abrupt = if_abrupt_reject_promise(global_object, iterator_record_or_error, promise_capability); abrupt.has_value()) - return abrupt.value(); - auto* iterator_record = iterator_record_or_error.release_value(); + auto promise_resolve = TRY_OR_REJECT(vm, promise_capability, get_promise_resolve(global_object, constructor)); + auto* iterator_record = TRY_OR_REJECT(vm, promise_capability, get_iterator(global_object, vm.argument(0))); auto result = perform_promise_any(global_object, *iterator_record, constructor, promise_capability, promise_resolve); if (auto* exception = vm.exception()) { @@ -379,8 +341,7 @@ JS_DEFINE_OLD_NATIVE_FUNCTION(PromiseConstructor::any) result_error = iterator_close(*iterator_record, move(result_error)); } - auto abrupt = if_abrupt_reject_promise(global_object, result_error, promise_capability); - return abrupt.value(); + TRY_OR_REJECT(vm, promise_capability, result_error); } return result; @@ -395,15 +356,8 @@ JS_DEFINE_OLD_NATIVE_FUNCTION(PromiseConstructor::race) if (vm.exception()) return {}; - auto promise_resolve_or_error = get_promise_resolve(global_object, constructor); - if (auto abrupt = if_abrupt_reject_promise(global_object, promise_resolve_or_error, promise_capability); abrupt.has_value()) - return abrupt.value(); - auto promise_resolve = promise_resolve_or_error.release_value(); - - auto iterator_record_or_error = get_iterator(global_object, vm.argument(0)); - if (auto abrupt = if_abrupt_reject_promise(global_object, iterator_record_or_error, promise_capability); abrupt.has_value()) - return abrupt.value(); - auto* iterator_record = iterator_record_or_error.release_value(); + auto promise_resolve = TRY_OR_REJECT(vm, promise_capability, get_promise_resolve(global_object, constructor)); + auto* iterator_record = TRY_OR_REJECT(vm, promise_capability, get_iterator(global_object, vm.argument(0))); auto result = perform_promise_race(global_object, *iterator_record, constructor, promise_capability, promise_resolve); if (auto* exception = vm.exception()) { @@ -415,8 +369,7 @@ JS_DEFINE_OLD_NATIVE_FUNCTION(PromiseConstructor::race) result_error = iterator_close(*iterator_record, move(result_error)); // iterator_close() may invoke vm.call(), which VERIFYs no exception. } - auto abrupt = if_abrupt_reject_promise(global_object, result_error, promise_capability); - return abrupt.value(); + TRY_OR_REJECT(vm, promise_capability, result_error); } return result;