fix: panic on nil point on name check

[Shooks (Dansyuqri)]

Why

In checkNonIdentifierName, when name is nil, a panic occurs due to a nil pointer reference.

Fixes #63750

How

Adds a check on the name, instead of passing it to IsIdentifier. This prevents the panic when passing a nil pointer to IsIdentifier.
Returns an early nil if name is already nil.

Tests

• Add a test to cover anonymous and non-anonymous default function declarations

Verification

• There is an associated issue in the Backlog milestone (required)
• Code is up-to-date with the main branch
• You've successfully run npx hereby test
• You've successfully run npx hereby lint
• You've successfully run npx hereby check:format
• There are new or updated tests validating the change

[Shooks (Dansyuqri)]

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[Copilot]

Pull request overview

Prevents parser panics when JSDoc overloads annotate anonymous default-exported functions.

Changes:

• Safely handles nil function names during JSDoc reparsing.
• Adds regression coverage for anonymous and named default exports.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
tsc/internal/parser/reparser.go	Guards nil names before identifier validation.
tsc/internal/parser/parser_test.go	Tests anonymous and named JSDoc overload declarations.

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[Jake Bailey (jakebailey)]

This needs to be a regular compiler test, not a unit test

[Shooks (Dansyuqri)]

thanks Jake Bailey (@jakebailey) , I have updated as such

[Jake Bailey (jakebailey)]

Verified that this test crashes without the fix. Thanks.