The transformer generate incorrect code when referencing variables declared using using from closures

[hangxingliu]

Describe the bug

A reference error will be emitted when executing the code generated by swc that references a variable declared using using from closures. (See the sample input code below)

This issue can be re-produced in both of Typescript and JavaScript. The main part of a sample generated code looks like:

function main() {
    function readFile() {
        file.read();
    }
    try {
        var _usingCtx = _using_ctx();
        const file = _usingCtx.u(new File());
        readFile();
    } catch (_) {
        _usingCtx.e = _;
    } finally{
        _usingCtx.d();
    }
}

Executing this code can emit an reference error: file is not defined.

Moreover, here is the main part of the generated code from the official TypeScript transpiler (tsc), without this issue:

function main() {
    const env_1 = { stack: [], error: void 0, hasError: false };
    try {
        const file = __addDisposableResource(env_1, new File(), false);
        function readFile() {
            file.read();
            // ...
        }
        readFile();
    }
    catch (e_1) {
        env_1.error = e_1;
        env_1.hasError = true;
    }
    finally {
        __disposeResources(env_1);
    }
}

The link to this code on typescriptlang.org.

Input code

class File {
  read() {
    return 'content';
  }
  [Symbol.dispose]() {
    console.log(`closing the file ...`);
  }
}
function main() {
  using file = new File();
  function readFile() {
    file.read();
    // ...
  }
  readFile();
}

Config

{
  "jsc": {
    "parser": {
      "syntax": "ecmascript",
      "jsx": false,
      "explicitResourceManagement": true
    },
    "target": "es2022",
    "loose": false,
    "minify": {
      "compress": false,
      "mangle": false
    }
  },
  "module": {
    "type": "commonjs"
  },
  "minify": false,
  "isModule": true
}

Playground link (or link to the minimal reproduction)

https://play.swc.rs/?version=1.5.0&code=H4sIAAAAAAAAA0WOMQrDMAxFd59CW5zFOYDp2gt0LIW4jpIaHKnEDqGU3L22Y9JBIH2e%2Fv%2FWmxDg6jzCVwAsaAbZljUfcV0IGssUkWKjk7qnud8%2B85O9Glx4c8DH%2BZDAwB6V50n21nNwNEF8IYzZXynVt4fHLsaVbHRMMBtH1WAtfGEvQLiVWrK8nHgueMg1M%2BPqqK2L0HU5qVb941rsP5Y8dYDsAAAA&config=H4sIAAAAAAAAA2VPOw6DMAzdOQXy3KFi7B1YegMrNSgoP8VGAiHu3iRA2qqb38fv2VvTtjCxgke7pTGBgJEpVpwYXp3gkhggZZFV1EHgdqkTZ2lAw1Q5WoLRSsuT2M9RUY8OR7LkJFklzlSM%2B%2BEHwTiSlHzu7l13ZoPxnuk3G6x2eli%2Fr1PehkjMf0dYdKOp%2B0djc7aC9a%2B5iOfXsoaMcpr1bmL4OK%2FGmg6a%2B2u9PLO%2FAcfgY45GAQAA

SWC Info output

No response

Expected behavior

The expected behavior is for the code to be generated in a correct way like what tsc does that it runs without emitting reference errors

Actual behavior

No response

Version

1.5.0

Additional context

https://www.typescriptlang.org/docs/handbook/release-notes/typescript-5-2.html#using-declarations-and-explicit-resource-management

[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.