mlox/lox.t/closure/unused_later_closure.lox

// This is a regression test. When closing upvalues for discarded locals, it
// wouldn't make sure it discarded the upvalue for the correct stack slot.
//
// Here we create two locals that can be closed over, but only the first one
// actually is. When "b" goes out of scope, we need to make sure we don't
// prematurely close "a".
var closure;

{
  var a = "a";

  {
    var b = "b";
    fun returnA() {
      return a;
    }

    closure = returnA;

    if (false) {
      fun returnB() {
        return b;
      }
    }
  }

  print closure(); // expect: a
}