fix(parser): forbid invalid modifiers on module and global

[overlookmotel]

Error on invalid modifiers before module and global declarations.

Previously illegal syntax like this would be parsed without error:

protected accessor readonly async declare global {}
protected accessor readonly async global {}
protected accessor readonly async module "foo" {}

Discovered this bug while working on #15712.

Similar to #11713.

[overlookmotel]

• fix(parser): forbid invalid modifiers on module and global #15723 👈 (View in Graphite)
• perf(transformer/typescript): reverse order of checks #15722
• fix(ast)!: add TSGlobalDeclaration type #15712
• refactor(transformer/typescript): use exhaustive match #15711
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #15723 will not alter performance

_{Comparing 11-15-fix_parser_forbid_invalid_modifiers_on_module_and_global_ (4e1248e) with main (c167dfa)}

Summary

✅ 37 untouched

[Copilot]

Pull Request Overview

This PR adds validation to forbid invalid modifiers on module and global declarations in TypeScript. Previously, illegal syntax with multiple modifiers (like protected accessor readonly async declare global {}) would be parsed without error.

• Adds verify_modifiers calls to validate that only the declare modifier is allowed on module and global declarations
• Ensures consistency with similar validation done for other TypeScript declarations (enums, type aliases, interfaces)

Reviewed Changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated no comments.

File	Description
crates/oxc_parser/src/ts/statement.rs	Adds modifier validation for parse_ambient_external_module_declaration, parse_module_or_namespace_declaration, and parse_ts_global_declaration functions to reject invalid modifiers
tasks/coverage/snapshots/parser_typescript.snap	Updates test snapshots to reflect new error messages for invalid export modifier on module declarations

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[Boshen]

Merge activity

• Nov 18, 1:54 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Nov 18, 1:54 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Nov 18, 2:00 AM UTC: The Graphite merge queue couldn't merge this PR because it was not satisfying all requirements (Failed CI: 'Conformance').
• Nov 18, 11:42 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Nov 18, 11:49 AM UTC: camc314 added this pull request to the Graphite merge queue.
• Nov 18, 11:49 AM UTC: Merged by the Graphite merge queue.