fix(oxlint): do not panic on invalid no-unused-vars configuration

[Sysix]

I tried to return serde_json::Error::Error, but NoUnusedVarsOptions::try_from is returning diagnostics / strings, which can not easily be converted to serde_json::Error::Error (I could not achieve this :( ). So falling back to the default configuration, instead of panicking.

closes #17715

[Sysix]

• fix(oxlint): do not panic on invalid no-unused-vars configuration #17719 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #17719 will not alter performance

_{Comparing 01-06-fix_oxlint_do_not_panic_on_invalid_no-unused-vars_configuration (5a9e613) with main (4eb335c)}

Summary

✅ 4 untouched
⏩ 41 skipped¹

Footnotes

1. 41 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]

Merge activity

• Jan 6, 4:14 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Jan 6, 4:14 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Jan 6, 4:21 PM UTC: Merged by the Graphite merge queue.

[Copilot]

Pull request overview

This PR addresses issue #17715 where invalid configuration for the no-unused-vars rule causes the oxc language server to crash repeatedly. The fix prevents the panic by using .unwrap_or_default() instead of .unwrap() when parsing rule configuration.

• Replaces .unwrap() with .unwrap_or_default() to prevent panic on invalid configuration
• Falls back to default rule configuration when parsing fails
• Prevents language server crash loop on invalid config values

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[Copilot]

Using .unwrap_or_default() silently swallows configuration errors, which means users won't be notified when their configuration is invalid. The NoUnusedVarsOptions::try_from() implementation returns helpful OxcDiagnostic errors (e.g., "Invalid 'args' option for no-unused-vars: Expected one of [after-used, all, none], got 'nonex'"), but these error messages are completely lost.

While this prevents the panic, users will be confused when their configuration doesn't take effect and they get no feedback about why. Consider logging the error or finding a way to propagate it to the user instead of silently falling back to defaults.

Suggested change

	Ok(Self(Box::new(NoUnusedVarsOptions::try_from(value).unwrap_or_default())))
	NoUnusedVarsOptions::try_from(value)
	.map(|options| Self(Box::new(options)))
	.map_err(|diagnostic| serde_json::error::Error::custom(diagnostic.to_string()))