类型化类常量

8.2

<?php
interface I {
    // We may naively assume that the PHP constant is always a string.
    const PHP = 'PHP 8.2';
}

class Foo implements I {
    // But implementing classes may define it as an array.
    const PHP = [];
}

8.3

<?php
interface I {
    const string PHP = 'PHP 8.3';
}

class Foo implements I {
    const string PHP = [];
}

// Fatal error: Cannot use array as value for class constant
// Foo::PHP of type string

动态获取类常量

8.2

<?php
class Foo {
    const PHP = 'PHP 8.2';
}

$searchableConstant = 'PHP';

var_dump(constant(Foo::class . "::{$searchableConstant}"));

8.3

<?php
class Foo {
    const PHP = 'PHP 8.3';
}

$searchableConstant = 'PHP';

var_dump(Foo::{$searchableConstant});

新增 #[\Override] 属性

8.2

<?php
use PHPUnit\Framework\TestCase;

final class MyTest extends TestCase {
    protected $logFile;

    protected function setUp(): void {
        $this->logFile = fopen('/tmp/logfile', 'w');
    }

    protected function taerDown(): void {
        fclose($this->logFile);
        unlink('/tmp/logfile');
    }
}

// The log file will never be removed, because the
// method name was mistyped (taerDown vs tearDown).

8.3

<?php
use PHPUnit\Framework\TestCase;

final class MyTest extends TestCase {
    protected $logFile;

    protected function setUp(): void {
        $this->logFile = fopen('/tmp/logfile', 'w');
    }

    #[\Override]
    protected function taerDown(): void {
        fclose($this->logFile);
        unlink('/tmp/logfile');
    }
}

// Fatal error: MyTest::taerDown() has #[\Override] attribute,
// but no matching parent method exists

通过给方法添加 #[\Override] 属性，PHP 将确保在父类或实现的接口中存在同名的方法。添加该属性表示明确说明覆盖父方法是有意为之，并且简化了重构过程，因为删除被覆盖的父方法将被检测出来。

只读属性深拷贝

8.2

<?php
class PHP {
    public string $version = '8.2';
}

readonly class Foo {
    public function __construct(
        public PHP $php
    ) {}

    public function __clone(): void {
        $this->php = clone $this->php;
    }
}

$instance = new Foo(new PHP());
$cloned = clone $instance;

// Fatal error: Cannot modify readonly property Foo::$php

8.3

<?php
class PHP {
    public string $version = '8.2';
}

readonly class Foo {
    public function __construct(
        public PHP $php
    ) {}

    public function __clone(): void {
        $this->php = clone $this->php;
    }
}

$instance = new Foo(new PHP());
$cloned = clone $instance;

$cloned->php->version = '8.3';
readonly 属性现在可以在魔术方法 __clone 中被修改一次，以此实现只读属性的深拷贝。

新增 json_validate() 函数

<?php
var_dump(json_validate('{ "test": { "foo": "bar" } }')); // true

新增 Randomizer::getBytesFromString() 方法

<?php
$randomizer = new \Random\Randomizer();

$randomizer->getBytesFromString(
    'abcdefghijklmnopqrstuvwxyz0123456789',
    8,
);

生成特定长度的随机字符串。

新增 Randomizer::getFloat() 和 Randomizer::nextFloat() 方法

<?php
$randomizer = new \Random\Randomizer();

// 获取区间浮点数
$temperature = $randomizer->getFloat(
    -89.2,
    56.7,
    \Random\IntervalBoundary::ClosedClosed,
);

$chanceForTrue = 0.1;
// Randomizer::nextFloat() is equivalent to
// Randomizer::getFloat(0, 1, \Random\IntervalBoundary::ClosedOpen).
// The upper bound, i.e. 1, will not be returned.
$myBoolean = $randomizer->nextFloat() < $chanceForTrue;

命令行 linter 支持多个文件

php -l foo.php bar.php

新增 mb_str_pad 方法

用另一个多字节字符串填充一个多字节字符串到一定长度

<?php
var_dump(mb_str_pad('▶▶', 6, '❤❓❇', STR_PAD_RIGHT)); // string(18) "▶▶❤❓❇❤"
var_dump(mb_str_pad('▶▶', 6, '❤❓❇', STR_PAD_LEFT));  // string(18) "❤❓❇❤▶▶"
var_dump(mb_str_pad('▶▶', 6, '❤❓❇', STR_PAD_BOTH));  // string(18) "❤❓▶▶❤❓"

var_dump(mb_str_pad("🎉", 3, "祝", STR_PAD_LEFT)));   // string(10) "祝祝🎉"

新增 str_increment 和 str_decrement 方法

<?php
// 递增字符串
$str = 'ABC';
var_dump(str_decrement($str));    // ABD
// 递减字符串
$str = 'ZA';
var_dump(str_decrement($str));    // YZ