Bug 214379 – Support export namespace `export * as ns`

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Huáng Jùnliàng]

`export * as ns` is included in ES2020.

Expect: it works on Safari

Actual: Safari TP 109 throws warning that missing "from" after `*`.

Spec PR: https://github.com/tc39/ecma262/pull/1174

[Radar WebKit Bug Importer]

<rdar://problem/65699863>

[Yusuke Suzuki]

Created attachment 408905 [details]
Patch

WIP

[Yusuke Suzuki]

Created attachment 408990 [details]
Patch

[Ross Kirsling]

Comment on attachment 408990 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=408990&action=review

r=me. Thanks for the extra explanation over Slack.

> Source/JavaScriptCore/parser/NodesAnalyzeModule.cpp:89
> +            // export { * as v } from "mod"

This form can't use braces though, right?

> Source/JavaScriptCore/runtime/AbstractModuleRecord.cpp:779
> +    // Materialize *namespace* slot with module namespace object.
> +    // If module environment is not yet materialized, we will materialize it when materializing module environment.

The "it" here is a bit confusing upon first read. Maybe something like "...unless the module environment is not yet materialized, in which case we'll do it in setModuleEnvironment"?

> Source/JavaScriptCore/runtime/AbstractModuleRecord.cpp:782
> +        bool putResult = false;
> +        symbolTablePutTouchWatchpointSet(m_moduleEnvironment.get(), globalObject, vm.propertyNames->starNamespacePrivateName, moduleNamespaceObject, /* shouldThrowReadOnlyError */ false, /* ignoreReadOnlyErrors */ true, putResult);

nit: I know this is copied code, but it seems silly that one boolean is described using an identifier and the other two are described with block comments.

[Yusuke Suzuki]

Created attachment 409007 [details]
Patch

[Yusuke Suzuki]

Created attachment 409008 [details]
Patch

[Yusuke Suzuki]

Comment on attachment 408990 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=408990&action=review

>> Source/JavaScriptCore/parser/NodesAnalyzeModule.cpp:89
>> +            // export { * as v } from "mod"
> 
> This form can't use braces though, right?

Right, fixed.

>> Source/JavaScriptCore/runtime/AbstractModuleRecord.cpp:779
>> +    // If module environment is not yet materialized, we will materialize it when materializing module environment.
> 
> The "it" here is a bit confusing upon first read. Maybe something like "...unless the module environment is not yet materialized, in which case we'll do it in setModuleEnvironment"?

Sounds good!

>> Source/JavaScriptCore/runtime/AbstractModuleRecord.cpp:782
>> +        symbolTablePutTouchWatchpointSet(m_moduleEnvironment.get(), globalObject, vm.propertyNames->starNamespacePrivateName, moduleNamespaceObject, /* shouldThrowReadOnlyError */ false, /* ignoreReadOnlyErrors */ true, putResult);
> 
> nit: I know this is copied code, but it seems silly that one boolean is described using an identifier and the other two are described with block comments.

Fixed.

[Yusuke Suzuki]

iOS-wk2 failures are unrelated.
https://ews-build.webkit.org/#/builders/24/builds/25994

[Yusuke Suzuki]

Committed r267186: <https://trac.webkit.org/changeset/267186>