fix(transformer): optional-catch-binding unused variable side effect

[rzvxa]

Before this PR for this given case:

const _unused = "It's a lie, They gonna use me:(";
try {
    throw 0;
} catch {
  console.log(_unused);
}

We would've generated this:

const _unused = "It's a lie, They gonna use me:(";
try {
    throw 0;
} catch (_unused) {
  console.log(_unused);
}

This is incorrect, This PR aims to use the CreateVars trait in order to ensure the variable uniqueness.

Now it would output this:

const _unused = "It's a lie, They gonna use me:(";
try {
    throw 0;
} catch (_unused2) {
  console.log(_unused);
}

[rzvxa]

• fix(transformer): optional-catch-binding unused variable side effect #2822 👈
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #2822 will not alter performance

_{Comparing 03-26-fix_transformer_fix_optional-catch-binding_unsued_variable_side_effect (8afa459) with main (8c6936a)}

Summary

✅ 34 untouched benchmarks

[Dunqing]

There are no snapshots updated?

[rzvxa]

There are no snapshots updated?

No the tests on eslint don't consider this so it was passing anyway.

[rzvxa]

@Dunqing I can add the appropriate tests to the eslint if you find it relative to oxc.

[Dunqing]

@Dunqing I can add the appropriate tests to the eslint if you find it relative to oxc.

I prefer to add the test here. But this is babel repo 😅 https://github.com/babel/babel/blob/f856fc22d05bf886d1a58c5c91490e1af8f90c44/packages/babel-plugin-transform-optional-catch-binding/test/fixtures/optional-catch-bindings

[rzvxa]

I prefer to add the test here. But this is babel repo 😅 https://github.com/babel/babel/blob/f856fc22d05bf886d1a58c5c91490e1af8f90c44/packages/babel-plugin-transform-optional-catch-binding/test/fixtures/optional-catch-bindings

I agree, We may want to add our set of unit tests on top of esbuild compatibility checks. However, I would add a try-catch-shadow case there when I get the time. Even if we don't rely on it, It would be net positive.