hphp/hack/test/typecheck/ternary7.php

   1 <?hh
   2
   3 function takes_int(int $x): void { }
   4
   5 function f(): void {
   6   $a = 1;
   7   if (true) {} // this makes $a into a Tvar mapped to a Tunion[int]
   8   /* We used to unify both branches of a ternary expression, then falling back
   9    * to creating a Tunion if unification failed; this would create a false
  10    * positive error for the code below.
  11    */
  12   true ? null : $a;
  13   takes_int($a);
  14 }