Issue #3451611 by mfb, xjm, smustgrave, quietone: Fix the format=flowed;...

    // Join the body array into one string.

    $message['body'] = implode("\n\n", $message['body']);

    // Convert any HTML to plain-text.

    // Convert any HTML to plain text (which also wraps the mail body).

    $message['body'] = MailFormatHelper::htmlToText($message['body']);

    // Wrap the mail body for sending.

    $message['body'] = MailFormatHelper::wrapMail($message['body']);

    return $message;

  }

  }

  public function format(array $message) {

    // Convert any HTML to plain-text.

    foreach ($message['body'] as &$part) {

      // If the message contains HTML, convert it to plain text (which also

      // wraps the mail body).

      if ($part instanceof MarkupInterface) {

        $part = MailFormatHelper::htmlToText($part);

      }

      // If the message does not contain HTML, it still needs to be wrapped

      // properly.

      else {

        $part = MailFormatHelper::wrapMail($part);

      }

    // Check that the body headers were not wrapped even though some exceeded

    // 77 characters.

    $this->assertEquals($headers_in_body, $processed_headers, 'Headers in the body are not wrapped.');

    // Check that the body text is wrapped.

    $this->assertEquals(wordwrap($body, 77, " \n"), $processed_body, 'Body text is wrapped.');

    // Check that the body text is soft-wrapped according to the

    // "format=flowed; delsp=yes" encoding. When interpreting this encoding,

    // mail readers will delete a space at the end of the line; therefore an

    // extra trailing space should be present in the raw body (see RFC 3676).

    $this->assertEquals(wordwrap($body, 77, "  \n"), $processed_body, 'Body text is soft-wrapped.');

  }

}