public function toThrow()

in minitest/ExpectObj.hack [86:119]

• 33 lines of code
• 4 McCabe index (conditional complexity)

  public function toThrow<TEx as \Throwable>(
    classname<TEx> $ex,
    ?string $ex_message = null,
    ?string $_failure_message = null,
  ): TEx where T = (function(): mixed) {
    $thrown = null;
    try {
      $f = $this->value;
      $ret = $f();
      if ($ret is Awaitable<_>) {
        \HH\Asio\join($ret);
      }
    } catch (\Throwable $t) {
      $thrown = $t;
    }
    $thrown = expect($thrown)->toNotBeNull();
    self::assert(
      \is_a($thrown, $ex),
      $_failure_message ??
        'Expected to throw "'.$ex."\", but instead got:\n".$thrown->__toString()
    );
    if ($ex_message is nonnull) {
      self::assert(
        \strpos($thrown?->getMessage() ?? '', $ex_message) !== false,
        $_failure_message ??
          'Expected the exception message to be "'.
          $ex_message.
          "\", but instead got:\n".
          $thrown->__toString()
      );
    }
    /* HH_FIXME[4110] verified with is_a() */
    return $thrown;
  }