function test() {

var {a, b = 2} = {a:1};
try {
  eval("let {c = c} = {};");
  return false;
} catch(e){}
try {
  eval("let {c = d, d} = {d:1};");
  return false;
} catch(e){}
return a === 1 && b === 2;
      
}

if (!test())
    throw new Error("Test failed");