feat(napi/parser)!: represent empty optional fields on JS side as null

[overlookmotel]

Follow-on after #16383 and #16403.

While working on those I discovered an option NAPI-RS has to represent Option::None as null, instead of omitting the field entirely.

Use that option on the structs used for transferring errors and module record over to JS.

I think this is likely more performant because:

1. NAPI-RS can create all properties of the objects using only the faster node_api_create_object_with_properties API.
2. It produces consistent object shapes, so JS engine can better optimize code using these objects.

It also brings the shape of the data perfectly into line between standard transfer and raw transfer, and is consistent with how empty fields in the AST are represented as null.

I would have used this option before if I'd known it existed.

Breaking change

I've marked this as a breaking change because code consuming these objects would now need to check for empty fields with value === null instead of value === undefined.

However in practice, most people probably use !value or value ?? ..., so it's unlikely to affect many users. This only affects module record and errors anyway, not the AST itself, as we transfer that as JSON, not via NAPI.

[overlookmotel]

• fix(napi/parser): move ExportEntry::module_request field to first #16412
• feat(napi/parser)!: represent empty optional fields on JS side as null #16411 👈 (View in Graphite)
• main

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[Copilot]

Pull request overview

This PR enhances NAPI-RS data transfer by representing empty optional fields as null instead of omitting them entirely. This aligns the representation with how AST fields are handled and improves JS engine optimization through consistent object shapes.

Key Changes:

• Added use_nullable = true to NAPI object macros for module record and error structs
• Updated TypeScript type definitions to reflect | null instead of optional fields (?)
• Removed the removeNullProperties helper function that was previously needed to normalize outputs
• Updated all test snapshots to expect null values for empty optional fields

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
napi/parser/src/types.rs	Added use_nullable = true to ImportName, StaticExportEntry, ExportImportName, ExportExportName, and ExportLocalName structs
crates/oxc_napi/src/error.rs	Added use_nullable = true to OxcError and ErrorLabel structs
napi/parser/src-js/index.d.ts	Updated TypeScript type definitions to use `
napi/parser/test/parse.test.ts	Updated test expectations to include null values for empty optional fields
napi/parser/test/parse-raw-worker.ts	Removed removeNullProperties helper function and related field reordering logic
napi/parser/test/__snapshots__/esm.test.ts.snap	Updated all test snapshots to include null values for empty optional fields in module records

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[graphite-app]

Merge activity

• Dec 2, 11:30 PM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Dec 2, 11:36 PM UTC: Merged by the Graphite merge queue.