fix(linter): catch missing return type on exported arrow/function expressions

[wagenet]

Summary

• run_on_exported_expression_inner called walk::walk_arrow_function_expression (the raw walk function) instead of checker.visit_arrow_function_expression. The raw walk visits AST children but bypasses ExplicitTypesChecker::visit_arrow_function_expression, which is the method that calls check_arrow_without_return. Block-body arrow functions with no inner function expressions produced no diagnostic.
• Added symmetric fix for FunctionExpression: export default (function() { ... }) was silently ignored by the _ arm.

Incorrect behavior before fix

// Not flagged by oxlint, but should be
export default ({
    connectorTypeEnumCase,
    connectorFriendlyName,
}: {
    connectorTypeEnumCase: string;
    connectorFriendlyName: string;
}) => {
    return `${connectorTypeEnumCase}`;
};

Snapshot correction

export default () => (true ? () => {} : (): void => {}) now points to the outer exported arrow (the module boundary) instead of the inner () => {}.

Test plan

• Existing explicit_module_boundary_types tests all pass
• New fail test: destructured-param arrow with block body
• New fail test: export default (function() { ... })

🤖 Generated with Claude Code

[Copilot]

Pull request overview

Fixes typescript-eslint/explicit-module-boundary-types in oxc_linter so exported arrow/function expressions are checked via ExplicitTypesChecker’s visit_* methods (instead of raw AST walking), restoring diagnostics that were previously skipped or incorrectly attributed to inner functions.

Changes:

• Route exported ArrowFunctionExpression handling through checker.visit_arrow_function_expression so check_arrow_without_return runs.
• Add symmetric handling for exported FunctionExpression via checker.visit_function.
• Update snapshots and extend the rule’s test cases to cover the newly-detected failures and corrected label spans.

Reviewed changes

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

File	Description
crates/oxc_linter/src/rules/typescript/explicit_module_boundary_types.rs	Fix exported expression handling to use checker visitors (arrow + function expressions) and add regression tests.
crates/oxc_linter/src/snapshots/typescript_explicit_module_boundary_types.snap	Update expected diagnostics: correct span for exported conditional-arrow case; add snapshots for new failing cases.

[codspeed-hq]

Merging this PR will not alter performance

✅ 47 untouched benchmarks
⏩ 3 skipped benchmarks¹

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_{Comparing wagenet:worktree-explicit-module-boundary-types-fix (55ac140) with main (024f51c)}

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[camc314]

thank you!