fix(lint/noUnreachable): correctly analyze nested try-finally statements

[ah-yu]

Summary

Closes #1827

The noUnreachable rule offers two approaches for analysis

biome/crates/biome_js_analyze/src/analyzers/correctness/no_unreachable.rs

Lines 69 to 73 in 5394928

	if exceeds_complexity_threshold(cfg) {
	analyze_simple(cfg, &mut signals)
	} else {
	analyze_fine(cfg, &mut signals)
	}

The reported bug is caused by nested try statements, but it only occurs with analyze_simple.

Let's consider the following example (assuming the analysis is driven by analyze_simple)

try {
  try {
  } finally {
    if (mayThrow()) {
         // block 1
    }
    foo() // block 2
  }
} catch (e) {
  // block 3
}

• If the mayThrow() function throws an exception, then block 1 jumps to block 3
• If the mayThrow() function doesn't throw an exception, then block 1 jumps to block 2.

In the current implementation, we only handle the first scenario, but not the second. So we need to handle the second scenario.

Test Plan

Add a new test case

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[codspeed-hq]

CodSpeed Performance Report

Merging #1856 will not alter performance

_{⚠️ No base runs were found}

_{Falling back to comparing ah-yu:no_unreachable (e2811f7) with main (1957fb0)}

Summary

✅ 93 untouched benchmarks

[Conaclos]

Thanks for your contribution! We should also evaluate if other rules that use the control flow graph need to be updated.

[ah-yu]

Hi @Conaclos Thank you for the review! The fix is related to finally_fallthrough, and upon searching, I only found the noUnreachable rule using it.

I am not confident about the fix, could you please help check the PR description and see if the fix is heading in the right direction? Thanks!

[Conaclos]

Hi @Conaclos Thank you for the review! The fix is related to finally_fallthrough, and upon searching, I only found the noUnreachable rule using it.

I am not confident about the fix, could you please help check the PR description and see if the fix is heading in the right direction? Thanks!

Sorry I missed your answer.

Looking at the fix and the repro, this looks good to me :)

[Conaclos]

Thanks!