fix(ast_macros): do not panic in macro

[overlookmotel]

Previously if you edited an AST struct, adding or removing fields, #[ast] macro would panic because the fields of the struct don't match what it's expecting from the STRUCTS metadata which is generated by oxc_ast_tools.

It would cover the whole struct with red squiggles, with a cryptic error message. This was really annoying.

Instead, make the macro output a compile_error! macro invocation. This makes IDE and cargo build show an error saying that you need to run just ast to re-run the codegen. Also, because the macro doesn't crash any more, you don't have to re-start Rust Analyser once you've fixed the problem.

This is less annoying for humans, and also the more helpful error message will hopefully point AI in the right direction.

[overlookmotel]

• fix(ast_macros): do not panic in macro #13102 👈 (View in Graphite)
• refactor(ast_macros): simplify code #13101
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13102 will not alter performance

_{Comparing 08-14-fix_ast_macros_do_not_panic_in_macro (d676e04) with main (c138fad)¹}

Summary

✅ 34 untouched benchmarks

Footnotes

1. No successful run was found on main (d676e04) during the generation of this report, so c138fad was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[Copilot]

Pull Request Overview

This PR improves error handling in the #[ast] macro to provide better developer experience when AST structs are modified. Previously, the macro would panic with cryptic errors when struct fields didn't match the generated metadata, requiring IDE restarts. Now it generates helpful compile errors that guide users to run the codegen.

• Replaced panic behavior with graceful error handling using compile_error! macro
• Added better error messages directing users to run just ast for codegen
• Improved robustness of the assert_generated_derives function by handling parsing failures gracefully

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[overlookmotel]

Merge activity

• Aug 18, 7:15 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Aug 18, 10:14 PM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Aug 18, 10:25 PM UTC: Merged by the Graphite merge queue.