Function shouldThrowSyntaxError

deps/v8/test/mjsunit/harmony/optional-chaining.js:6–17

(script)

function shouldThrowSyntaxError(script) {
  let error;
  try {
    eval(script);
  } catch (e) {
    error = e;
  }

  if (!(error instanceof SyntaxError)) {
    throw new Error('Expected SyntaxError!');
  }
}

assertEquals(undefined?.valueOf(), undefined);
assertEquals(null?.valueOf(), undefined);