hphp/hack/test/enum_class/typing/typing.extends1.bad.php

   1 <?hh
   2 // Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
   3
   4 // User code
   5 function expect_int(int $_): void {}
   6 function expect_string(string $_): void {}
   7 function expect_num(num $_): void {}
   8
   9 interface ExBox {}
  10
  11 class Box<T> implements ExBox {
  12   public function __construct(public T $data)[] {}
  13 }
  14
  15 class IBox extends Box<int> {
  16   public function add(int $x)[write_props]: void {
  17     $this->data = $this->data + $x;
  18   }
  19 }
  20
  21 abstract final class Helper {
  22   public static function ibox()[]: IBox {
  23     return new IBox(42);
  24   }
  25 }
  26
  27 // Enum Class user code
  28 enum class E: ExBox {
  29    Box<string> A = new Box('bli');
  30    IBox B = Helper::ibox();
  31    Box<int> B2 = new Box(42);
  32 }
  33
  34 enum class F: ExBox extends E {
  35    Box<num> C = new Box(3.14);
  36 }
  37
  38 abstract class Base {
  39   abstract const type TEnum as E;
  40
  41   public function get<T>(HH\MemberOf<this::TEnum, Box<T>> $param): T {
  42     return $param->data;
  43   }
  44
  45   public static function dictGen(): dict<string, ExBox> {
  46     $dict = dict[];
  47     $ts = type_structure(static::class, 'TEnum');
  48     $cls = $ts['classname'];
  49     foreach ($cls::getValues() as $key => $elt) {
  50       $dict[$key] = $elt;
  51     }
  52     return $dict;
  53   }
  54 }
  55
  56 class Ext extends Base {
  57   const type TEnum = E; // [0]
  58 }
  59
  60 function test_constraint(): void {
  61   $ext = new Ext();
  62   echo $ext->get(F::C); // F vs E, because of [0].
  63   echo "\n";
  64 }