feat(mangler): support keep_names option

[sapphi-red]

Adds support for keepNames in mangler.
The current implementration does not reuse the name kept. For example, for this input,

function e() {}
function foo() {
  var bar = 1;
  console.log(bar)
}

the ideal output is

function e() {}
function foo() {
  var e = 1;
  console.log(e)
}

(because e is not used inside foo and can be reused)
but the current output is

function e() {}
function foo() {
  var t = 1;
  console.log(t)
}

. I guess this isn't a problem in most cases as you won't use many short names for functions / classes.

close #9711

[sapphi-red]

Warning

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Learn more

• feat(mangler): support keep_names option #9873 👈 (View in Graphite)
• feat(semantics): collect symbols used for function / class names #9872
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #9873 will create unknown performance changes

_{Comparing 03-18-feat_mangler_support_keepnames_option (421163f) with 03-18-feat_semantics_collect_symbols_used_for_function___class_names (af0a969)}

Summary

🆕 33 new benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
🆕	codegen[checker.ts]	N/A	22.6 ms	N/A
🆕	codegen_sourcemap[checker.ts]	N/A	65.7 ms	N/A
🆕	isolated-declarations[vue-id.ts]	N/A	57.8 ms	N/A
🆕	lexer[RadixUIAdoptionSection.jsx]	N/A	21.1 µs	N/A
🆕	lexer[antd.js]	N/A	24.1 ms	N/A
🆕	lexer[cal.com.tsx]	N/A	5.7 ms	N/A
🆕	lexer[checker.ts]	N/A	14.5 ms	N/A
🆕	lexer[pdf.mjs]	N/A	3.8 ms	N/A
🆕	linter[RadixUIAdoptionSection.jsx]	N/A	2.7 ms	N/A
🆕	linter[cal.com.tsx]	N/A	1.2 s	N/A
🆕	linter[checker.ts]	N/A	3 s	N/A
🆕	mangler[antd.js]	N/A	16 ms	N/A
🆕	mangler[react.development.js]	N/A	294.2 µs	N/A
🆕	mangler[typescript.js]	N/A	39.5 ms	N/A
🆕	minifier[antd.js]	N/A	163.2 ms	N/A
🆕	minifier[react.development.js]	N/A	1.8 ms	N/A
🆕	minifier[typescript.js]	N/A	288.3 ms	N/A
🆕	estree[checker.ts]	N/A	87.5 ms	N/A
🆕	parser[RadixUIAdoptionSection.jsx]	N/A	91.2 µs	N/A
🆕	parser[antd.js]	N/A	112.6 ms	N/A
...	...	...	...	...

ℹ️ Only the first 20 benchmarks are displayed. Go to the app to view all benchmarks.