[[HostDefined]]
@@ -11926,16 +11937,27 @@
An implementation of HostMakeJobCallback must conform to the following requirements:
- - It must return a JobCallback Record whose [[Callback]] field is _callback_.
+ - It must return a JobCallback Record whose [[Callback]] field is _callback_, and [[ScriptOrModule]] field is the result of GetActiveScriptOrModule().
The default implementation of HostMakeJobCallback performs the following steps when called:
- 1. Return the JobCallback Record { [[Callback]]: _callback_, [[HostDefined]]: ~empty~ }.
+ 1. Let _scriptOrModule_ be GetActiveScriptOrModule().
+ 1. Return the JobCallback Record { [[Callback]]: _callback_, [[ScriptOrModule]]: _scriptOrModule_, [[HostDefined]]: ~empty~ }.
ECMAScript hosts that are not web browsers must use the default implementation of HostMakeJobCallback.
This is called at the time that the callback is passed to the function that is responsible for its being eventually scheduled and run. For example, `promise.then(thenAction)` calls MakeJobCallback on `thenAction` at the time of invoking `Promise.prototype.then`, not at the time of scheduling the reaction Job.
+
+
+ An example of when _scriptOrModule_ is not *null*, and saving it in this way is useful, is the following:
+
+ Promise.resolve('import(`./example.mjs`)').then(eval);
+
+ Without this step (and the steps that use it in HostCallJobCallback), the result of GetActiveScriptOrModule() would be *null* when the `import()` call is evaluated, since `eval()` is a built-in function that does not originate from any particular script.
+
+ With this step in place, the active _scriptOrModule_ is propagated from the above code into the job, allowing the `import()` call to use the original script's base URL appropriately.
+
@@ -11950,6 +11972,7 @@
An implementation of HostCallJobCallback must conform to the following requirements:
+ - It must perform implementation-defined steps such that _jobCallback_.[[ScriptOrModule]] is the active script or module at the time of _job_'s invocation.
- It must perform and return the result of Call(_jobCallback_.[[Callback]], _V_, _argumentsList_).
@@ -11958,7 +11981,17 @@
The default implementation of HostCallJobCallback performs the following steps when called:
1. Assert: IsCallable(_jobCallback_.[[Callback]]) is *true*.
- 1. Return ? Call(_jobCallback_.[[Callback]], _V_, _argumentsList_).
+ 1. Let _callerContext_ be the running execution context.
+ 1. If _callerContext_ is not already suspended, suspend _callerContext_.
+ 1. Let _jobContext_ be a new execution context.
+ 1. Let _scriptOrModule_ be _jobCallback_.[[ScriptOrModule]].
+ 1. If _scriptOrModule_ is not *null*, then
+ 1. Set the Realm of _jobContext_ to _scriptOrModule_.[[Realm]].
+ 1. Set the ScriptOrModule of _jobContext_ to _scriptOrModule_.
+ 1. Perform any necessary implementation-defined initialization of _jobContext_.
+ 1. Let _result_ be Completion(Call(_jobCallback_.[[Callback]], _V_, _argumentsList_)).
+ 1. Remove _jobContext_ from the execution context stack and restore _callerContext_ as the running execution context.
+ 1. Return ? _result_.
ECMAScript hosts that are not web browsers must use the default implementation of HostCallJobCallback.
@@ -11992,7 +12025,6 @@
An implementation of HostEnqueuePromiseJob must conform to the requirements in as well as the following:
- If _realm_ is not *null*, each time _job_ is invoked the implementation must perform implementation-defined steps such that execution is prepared to evaluate ECMAScript code at the time of _job_'s invocation.
- - Let _scriptOrModule_ be GetActiveScriptOrModule() at the time HostEnqueuePromiseJob is invoked. If _realm_ is not *null*, each time _job_ is invoked the implementation must perform implementation-defined steps such that _scriptOrModule_ is the active script or module at the time of _job_'s invocation.
- Jobs must run in the same order as the HostEnqueuePromiseJob invocations that scheduled them.
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