fix(transfomer/using): remove use of child ids

[camc314]

fixes #9744

[camc314]

• fix(transformer/using): fix bindings scope mismatches #9962
• fix(transfomer/using): remove use of child ids #9961 👈 (View in Graphite)
• fix(transformer/using): correctly reparent scopes in for of stmt #9960
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #9961 will not alter performance

_{Comparing c/03-22-fix_transfomer_using_remove_use_of_child_ids (021f76c) with main (2c53a72)}

Summary

✅ 33 untouched benchmarks

[overlookmotel]

Suggested change

	pub fn remove_child_scope(&mut self, scope_id: ScopeId, child_scope_ids: ScopeId) {
	pub fn remove_child_scope(&mut self, scope_id: ScopeId, child_scope_id: ScopeId) {

[overlookmotel]

What I was trying to say in previous comment is that this can be more efficient than remove_child_scopes, because you're only removing a single ID.

let child_ids = &mut cell.scope_child_ids[scope_id.index()];
let index = child_ids.iter().position(|&scope_id| scope_id == child_scope_id).unwrap();
child_ids.swap_remove(index);

Note that retain shifts up all following entries in the Vec (slow if there's lots of them), whereas swap_remove just moves 1 entry (same cheap cost, no matter how many entries in the Vec). And position will only search until it finds 1st match, whereas retain will carry on searching all the entries after its found a match (wasted work in this case because there can be only 1 match).

Warning: The unwrap() will panic if the ScopeId isn't found. That means this method must not be called unless the option to record child scope IDs is enabled. Method needs a comment to that effect.

[camc314]

ahhh i see, thanks for explaining

[overlookmotel]

I think more logic could be moved into this method - like generating the CatchClause and finally BlockStatement too. Unless I'm missing something, that logic looks identical across all the call sites too.

[camc314]

yeah you're right. when i origannally looked, i thought there'd end up being a ton of args, but since the catch/finalizer are basically have the same args, it's not bad