es(minify): if_return plus sequence optimize make code run in wrong order

[stormslowly]

Describe the bug

using swc_core: 0.101.4

just parse, resolve, optimize to the input code, then final generated code run in the wrong order.

in the input code, the hook will not be called, is async is false

after optimize

function bug(r, e) {
  var i;
  return e && isPromiseLike((i = r())) ? i : 0;
}

Input code

export function bug(hook, async) {
  var ret;
  ret = hook();
  if (!(async && isPromiseLike(ret))) {
    return 0;
  }
  return ret;
}

Config

No response

Playground link (or link to the minimal reproduction)

https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=b61031e4d72c3952b521891a3b3f7955

SWC Info output

No response

Expected behavior

no matter what value async is, function hook should always be called.

Actual behavior

after optimize

function bug(r, e) {
  var i;
  return e && isPromiseLike((i = r())) ? i : 0;
}

if e( async) is false, the r(hook) will never be called

Version

0.101.4

Additional context

config CompressOption with below, code works as expect

    sequences: 0,
    if_return: false,
    ..Default::default()

[stormslowly]

can not be reproduced in https://play.swc.rs with swc 1.7.4 nor nightly

[stormslowly]

@kdy1 any hint for me? maybe i can help to fix it

[kdy1]

It's not a bug of SWC minifier; it's wrong usage I guess

[kdy1]

You may need paren_remover and fixer

[kdy1]

See: https://github.com/swc-project/swc/blob/ede1a52cb8fb681ca08c54880c75c9b115c7a906/crates/swc_ecma_minifier/examples/minifier.rs

[kdy1]

Can you try the example minifier with your input?

[stormslowly]

Can you try the example minifier with your input?

yes, it works as expected .

i am a little confused to when/where to use fixer? after calling optimize ?

[kdy1]

After applying the name mangler or the hygiene pass. optimize applies the name mangler (if mangle option is specified), so it's after optimize in this case.

[stormslowly]

thx a lot

[swc-bot]

This closed issue has been automatically locked because it had no new activity for a month. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.