php 8.1 - 旧脚本中已弃用返回类型

Question

尝试更新到 php 8.1 并注意到这个已弃用的通知出现在我想要处理的错误日志中。

[14-Feb-2022 14:48:25 UTC] PHP Deprecated: Return type of TLDExtractResult::offsetExists($offset) should either be compatible with ArrayAccess::offsetExists(mixed $offset): bool, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /home/example/public_html/assets/tldextract/tldextract.php on line 299

我能够抑制警告，但实际上想更新脚本，这样将来就不会出现问题。

//public function offsetExists($offset) {
//  return array_key_exists($offset, $this->fields);
//}

#[\ReturnTypeWillChange]
public function offsetExists(mixed $offset) {
    return array_key_exists($offset, $this->fields);
}

这是有问题的代码部分：

class TLDExtractResult implements ArrayAccess {
    private $fields;

    public function __construct($subdomain, $domain, $tld) {
        $this->fields = array(
            'subdomain' => $subdomain,
            'domain'    => $domain,
            'tld'       => $tld,
        );
    }

    public function __get($name) {
        if ( array_key_exists($name, $this->fields) ) {
            return $this->fields[$name];
        }
        throw new OutOfRangeException(sprintf('Unknown field "%s"', $name));
    }

    public function __isset($name) {
        return array_key_exists($name, $this->fields);
    }

    public function __set($name, $value) {
        throw new LogicException('Can\'t modify an immutable object.');
    }

    public function __toString() {
        return sprintf('%s(subdomain=\'%s\', domain=\'%s\', tld=\'%s\')', __CLASS__, $this->subdomain, $this->domain, $this->tld);
    }

    //public function offsetExists($offset) {
    //  return array_key_exists($offset, $this->fields);
    //}
    
    #[\ReturnTypeWillChange]
    public function offsetExists(mixed $offset) {
        return array_key_exists($offset, $this->fields);
    }

    //public function offsetGet($offset) {
    //  return $this->__get($offset);
    //}

    #[\ReturnTypeWillChange]
    public function offsetGet(mixed $offset) {
        return $this->__get($offset);
    }

    //public function offsetSet($offset, $value) {
    //  throw new LogicException(sprintf('Can\'t modify an immutable object. You tried to set "%s".', $offset));
    //}

    #[\ReturnTypeWillChange]
    public function offsetSet(mixed $offset, $value) {
        throw new LogicException(sprintf('Can\'t modify an immutable object. You tried to set "%s".', $offset));
    }

    //public function offsetUnset($offset) {
    //  throw new LogicException(sprintf('Can\'t modify an immutable object. You tried to unset "%s".', $offset));
    //}

    #[\ReturnTypeWillChange]
    public function offsetUnset(mixed $offset) {
        throw new LogicException(sprintf('Can\'t modify an immutable object. You tried to unset "%s".', $offset));
    }

    /**
     * Get the domain name components as a native PHP array.
     * The returned array will contain these keys: 'subdomain', 'domain' and 'tld'.
     *
     * @return array
     */
    public function toArray() {
        return $this->fields;
    }
}

php 8.1 到底不喜欢什么？这比我通常使用 php 所做的稍高一些，但不太确定这个问题。听起来需要指定特定的返回类型？

Answer 1

是的，您可以指定与接口的各种方法所指示的返回类型相匹配的返回类型，ArrayAccess如手册中所示。例如，对于您问题中的弃用消息中的特定方法，如下所示：

public function offsetExists(mixed $offset): bool {
    return array_key_exists($offset, $this->fields);
}