Reflect.construct incorrectly calls newTarget, causing infinite loops about harmony-reflect HOT 1 CLOSED

You are right: if newTarget is different from target, we still need to call target, just with a custom instance. Unfortunately the newTarget option cannot be perfectly emulated in pure ES5 as there is no way to pass a custom newTarget to the [[Construct]] internal method of a function (well, the only way to do that is through Reflect.construct in ES6, but that's the precisely the method we are shimming)

I patched the method to continue to use the bound function approach when newTarget is not set (or is equal to target). The advantage being that this approach will work even if target is an ES6 class constructor function.

If newTarget is set, then we fall back to creating a custom instance and calling the target's [[Call]] internal method with the custom instance. This works for plain constructor functions, but will fail for ES6 class constructors as they must be invoked using the new operator.

Thanks for reporting!

from harmony-reflect.