hphp/hack/test/ifc/check/mut_array_control_flow.php

   1 <?hh
   2
   3 class C {
   4   <<__InferFlows>>
   5   public function __construct(
   6     <<__Policied("I")>>
   7     public int $i,
   8     <<__Policied("J")>>
   9     public int $j,
  10   ) {}
  11 }
  12
  13 <<__InferFlows>>
  14 function ok_vector_ix(C $c, Vector<int> $vector): void {
  15   $vector[] = $c->i; // Force lump of vector to be I
  16
  17   $c->j = 0; // OK because vector append does not raise an exception
  18 }
  19
  20 <<__InferFlows>>
  21 function ok_map_extend(C $c, Map<string,int> $map): void {
  22   $map['hello'] = $c->i; // Force lump of vector to be I
  23
  24   $c->j = 0; // OK because map extension does not raise an exception
  25 }
  26
  27 <<__InferFlows>>
  28 function leak_via_exn(C $c, Vector<int> $vector): void {
  29   $vector[0] = $c->i; // Force lump of vector to be I
  30
  31   // There is a flow from PC which is governed by length of vector due to the
  32   // conditional exception. The length is governed by the lump policy.
  33   $c->j = 0; // I flows into J
  34 }