hphp/hack/test/typecheck/typehole/T12678205.php

   1 <?hh // strict
   2 // Copyright 2004-present Facebook. All Rights Reserved.
   3
   4 class B { }
   5 class C {
   6   // These shape indices are
   7   // - not equal as far as static type-checking is concerned
   8   // - equal for runtime indexing :-(
   9   // So unsound
  10   const string OfB = "whatevs";
  11   const string OfC = "whatevs";
  12   public function Foo():void { echo 'Foo'; }
  13 }
  14 type ShapeTy = shape(C::OfB => B, C::OfC => C);
  15 function DoIt(ShapeTy $x):void {
  16     $c = $x[C::OfC];
  17     $c->Foo();
  18   }
  19
  20 <<__EntryPoint>>
  21 function BreakIt():void {
  22 // Sensitive to order: this will not fail at runtime
  23 // $s = shape(C::OfB => new B(), C::OfC => new C());
  24 // But this will
  25   $s = shape(C::OfC => new C(), C::OfB => new B());
  26   DoIt($s);
  27 }