+ NewPromiseReactionJob (
+ _reaction_: a PromiseReaction Record,
+ _argument_: an ECMAScript language value,
+ ): a Record with fields [[Job]] (a Job Abstract Closure) and [[Realm]] (a Realm Record or *null*)
+
+
+
description
+
It returns a new Job Abstract Closure that applies the appropriate handler to the incoming value, and uses the handler's return value to resolve or reject the derived promise associated with that handler.
+
+
+ 1. Let _job_ be a new Job Abstract Closure with no parameters that captures _reaction_ and _argument_ and performs the following steps when called:
+ 1. Let _promiseCapability_ be _reaction_.[[Capability]].
+ 1. Let _type_ be _reaction_.[[Type]].
+ 1. Let _handler_ be _reaction_.[[Handler]].
+ 1. If _handler_ is ~empty~, then
+ 1. If _type_ is ~Fulfill~, let _handlerResult_ be NormalCompletion(_argument_).
+ 1. Else,
+ 1. Assert: _type_ is ~Reject~.
+ 1. Let _handlerResult_ be ThrowCompletion(_argument_).
+ 1. Else, let _handlerResult_ be Completion(HostCallJobCallback(_handler_, *undefined*, « _argument_ »)).
+ 1. If _promiseCapability_ is *undefined*, then
+ 1. Assert: _handlerResult_ is not an abrupt completion.
+ 1. Return ~empty~.
+ 1. Assert: _promiseCapability_ is a PromiseCapability Record.
+ 1. If _handlerResult_ is an abrupt completion, then
+ 1. Return ? Call(_promiseCapability_.[[Reject]], *undefined*, « _handlerResult_.[[Value]] »).
+ 1. Let _previousContextMapping_ be AsyncContextSwap(_handler_.[[AsyncContextSnapshot]]).
+ 1. Let _rejectResult_ be Completion(Call(_promiseCapability_.[[Reject]], *undefined*, « _handlerResult_.[[Value]] »)).
+ 1. AsyncContextSwap(_previousContextMapping_).
+ 1. Return _rejectResult_.
+ 1. Else,
+ 1. Return ? Call(_promiseCapability_.[[Resolve]], *undefined*, « _handlerResult_.[[Value]] »).
+ 1. Let _handlerRealm_ be *null*.
+ 1. If _reaction_.[[Handler]] is not ~empty~, then
+ 1. Let _getHandlerRealmResult_ be Completion(GetFunctionRealm(_reaction_.[[Handler]].[[Callback]])).
+ 1. If _getHandlerRealmResult_ is a normal completion, set _handlerRealm_ to _getHandlerRealmResult_.[[Value]].
+ 1. Else, set _handlerRealm_ to the current Realm Record.
+ 1. NOTE: _handlerRealm_ is never *null* unless the handler is *undefined*. When the handler is a revoked Proxy and no ECMAScript code runs, _handlerRealm_ is used to create error objects.
+ 1. Return the Record { [[Job]]: _job_, [[Realm]]: _handlerRealm_ }.
+
+
+
+
+
+ NewPromiseResolveThenableJob (
+ _promiseToResolve_: a Promise,
+ _thenable_: an Object,
+ _then_: a JobCallback Record,
+ ): a Record with fields [[Job]] (a Job Abstract Closure) and [[Realm]] (a Realm Record)
+
+
+
+
+ 1. Let _job_ be a new Job Abstract Closure with no parameters that captures _promiseToResolve_, _thenable_, and _then_ and performs the following steps when called:
+ 1. Let _resolvingFunctions_ be CreateResolvingFunctions(_promiseToResolve_).
+ 1. Let _thenCallResult_ be Completion(HostCallJobCallback(_then_, _thenable_, « _resolvingFunctions_.[[Resolve]], _resolvingFunctions_.[[Reject]] »)).
+ 1. If _thenCallResult_ is an abrupt completion, then
+ 1. Return ? Call(_resolvingFunctions_.[[Reject]], *undefined*, « _thenCallResult_.[[Value]] »).
+ 1. Let _previousContextMapping_ be AsyncContextSwap(_then_.[[AsyncContextSnapshot]]).
+ 1. Let _rejectResult_ be Completion(Call(_resolvingFunctions_.[[Reject]], *undefined*, « _thenCallResult_.[[Value]] »)).
+ 1. AsyncContextSwap(_previousContextMapping_).
+ 1. Return _rejectResult_.
+ 1. Return ? _thenCallResult_.
+ 1. Let _getThenRealmResult_ be Completion(GetFunctionRealm(_then_.[[Callback]])).
+ 1. If _getThenRealmResult_ is a normal completion, let _thenRealm_ be _getThenRealmResult_.[[Value]].
+ 1. Else, let _thenRealm_ be the current Realm Record.
+ 1. NOTE: _thenRealm_ is never *null*. When _then_.[[Callback]] is a revoked Proxy and no code runs, _thenRealm_ is used to create error objects.
+ 1. Return the Record { [[Job]]: _job_, [[Realm]]: _thenRealm_ }.
+
+
+
This Job uses the supplied thenable and its `then` method to resolve the given promise. This process must take place as a Job to ensure that the evaluation of the `then` method occurs after evaluation of any surrounding code has completed.