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    <h3>Editing: IsType.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php declare(strict_types=1);
/*
 * This file is part of PHPUnit.
 *
 * (c) Sebastian Bergmann &lt;sebastian@phpunit.de&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace PHPUnit\Framework\Constraint;

use function gettype;

use function is_array;
use function is_bool;
use function is_callable;
use function is_float;
use function is_int;
use function is_iterable;
use function is_numeric;
use function is_object;
use function is_scalar;
use function is_string;
use function sprintf;
use PHPUnit\Framework\Exception;

/**
 * @no-named-arguments Parameter names are not covered by the backward compatibility promise for PHPUnit
 */
final class IsType extends Constraint
{
    /**
     * @var string
     */
    public const TYPE_ARRAY = 'array';

    /**
     * @var string
     */
    public const TYPE_BOOL = 'bool';

    /**
     * @var string
     */
    public const TYPE_FLOAT = 'float';

    /**
     * @var string
     */
    public const TYPE_INT = 'int';

    /**
     * @var string
     */
    public const TYPE_NULL = 'null';

    /**
     * @var string
     */
    public const TYPE_NUMERIC = 'numeric';

    /**
     * @var string
     */
    public const TYPE_OBJECT = 'object';

    /**
     * @var string
     */
    public const TYPE_RESOURCE = 'resource';

    /**
     * @var string
     */
    public const TYPE_CLOSED_RESOURCE = 'resource (closed)';

    /**
     * @var string
     */
    public const TYPE_STRING = 'string';

    /**
     * @var string
     */
    public const TYPE_SCALAR = 'scalar';

    /**
     * @var string
     */
    public const TYPE_CALLABLE = 'callable';

    /**
     * @var string
     */
    public const TYPE_ITERABLE = 'iterable';

    /**
     * @var array&lt;string,bool&gt;
     */
    private const KNOWN_TYPES = [
        'array'             =&gt; true,
        'boolean'           =&gt; true,
        'bool'              =&gt; true,
        'double'            =&gt; true,
        'float'             =&gt; true,
        'integer'           =&gt; true,
        'int'               =&gt; true,
        'null'              =&gt; true,
        'numeric'           =&gt; true,
        'object'            =&gt; true,
        'real'              =&gt; true,
        'resource'          =&gt; true,
        'resource (closed)' =&gt; true,
        'string'            =&gt; true,
        'scalar'            =&gt; true,
        'callable'          =&gt; true,
        'iterable'          =&gt; true,
    ];

    /**
     * @var string
     */
    private $type;

    /**
     * @throws Exception
     */
    public function __construct(string $type)
    {
        if (!isset(self::KNOWN_TYPES[$type])) {
            throw new Exception(
                sprintf(
                    'Type specified for PHPUnit\Framework\Constraint\IsType &lt;%s&gt; ' .
                    'is not a valid type.',
                    $type,
                ),
            );
        }

        $this-&gt;type = $type;
    }

    /**
     * Returns a string representation of the constraint.
     */
    public function toString(): string
    {
        return sprintf(
            'is of type &quot;%s&quot;',
            $this-&gt;type,
        );
    }

    /**
     * Evaluates the constraint for parameter $other. Returns true if the
     * constraint is met, false otherwise.
     *
     * @param mixed $other value or object to evaluate
     */
    protected function matches($other): bool
    {
        switch ($this-&gt;type) {
            case 'numeric':
                return is_numeric($other);

            case 'integer':
            case 'int':
                return is_int($other);

            case 'double':
            case 'float':
            case 'real':
                return is_float($other);

            case 'string':
                return is_string($other);

            case 'boolean':
            case 'bool':
                return is_bool($other);

            case 'null':
                return null === $other;

            case 'array':
                return is_array($other);

            case 'object':
                return is_object($other);

            case 'resource':
                $type = gettype($other);

                return $type === 'resource' || $type === 'resource (closed)';

            case 'resource (closed)':
                return gettype($other) === 'resource (closed)';

            case 'scalar':
                return is_scalar($other);

            case 'callable':
                return is_callable($other);

            case 'iterable':
                return is_iterable($other);

            default:
                return false;
        }
    }
}
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