CustomEvent thrown TypeError is not an instance of TypeError

[CMCDragonkai]

I noticed this while using Node 20.x and using the new CustomEvent global.

Inside nodejs this answers true:

try { new CustomEvent('abc', 'abc') } catch (e) { console.log(e instanceof TypeError); }

However when running inside jest it ends up producing false instead.

Initial research points to transpilation being where the source of this problem is likely. However it could also be a jest upstream situation.

[kdy1]

Please provide a minimal repro

[kdy1]

jsc.target (or env) in .swcrc matters here.

Can you try running output at https://play.swc.rs/?version=1.3.74&code=H4sIAAAAAAAAAyspqlSoVshLLVdwLi0uyc91LUvNK9FQT0xKVtdRAFOaCrUKyYklyRkKGqmaQLXJ%2BXnF%2BTmpejn56RqpCpl5xSWJecmp%2BWkKIZUFqa5FRflFmtYKtVwAvdDWElkAAAA%3D&config=H4sIAAAAAAAAA1WPSw7DIAwF9zkF8rrbdtE79BCIOhERP9mOVBTl7oUE0maH3xszsA5KwcwGnmotxzIkTYx0ziXhHER%2FSgKSE7IhmwRuvRWu1agd4x5tRwOiaUKpW8j3hoOLkbHjLfM22DH%2FC030iZD5ClZUh8nhVTc0Jfj4XvayfaQ%2B9tA%2F4Ad12XkxWH71TaEFh%2B0LYuVI0xQBAAA%3D?

[kdy1]

Roughly

function _instanceof(left, right) {
    if (right != null && typeof Symbol !== "undefined" && right[Symbol.hasInstance]) {
        return !!right[Symbol.hasInstance](left);
    } else {
        return left instanceof right;
    }
}
try {
    new CustomEvent("abc", "abc");
} catch (e) {
    console.log(_instanceof(e, TypeError));
}

[CMCDragonkai]

I'm using:

  transform: {
    "^.+\\.(t|j)sx?$": [
      "@swc/jest",
      {
        jsc: {
          parser: {
            syntax: "typescript",
            tsx: true,
            decorators: compilerOptions.experimentalDecorators,
            dynamicImport: true,
          },
          target: compilerOptions.target.toLowerCase(),
          keepClassNames: true,
        },
      }
    ],
  },

Discovered here MatrixAI/js-events#2 while testing. I ended up just changing my code to do this e.name === 'TypeError' as that worked fine.

Where the target is "target": "ES2022",.