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    <h3>Editing: ObjectEquals.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 get_class;
use function is_object;
use PHPUnit\Framework\ActualValueIsNotAnObjectException;
use PHPUnit\Framework\ComparisonMethodDoesNotAcceptParameterTypeException;
use PHPUnit\Framework\ComparisonMethodDoesNotDeclareBoolReturnTypeException;
use PHPUnit\Framework\ComparisonMethodDoesNotDeclareExactlyOneParameterException;
use PHPUnit\Framework\ComparisonMethodDoesNotDeclareParameterTypeException;
use PHPUnit\Framework\ComparisonMethodDoesNotExistException;
use ReflectionNamedType;
use ReflectionObject;

/**
 * @no-named-arguments Parameter names are not covered by the backward compatibility promise for PHPUnit
 */
final class ObjectEquals extends Constraint
{
    /**
     * @var object
     */
    private $expected;

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

    public function __construct(object $object, string $method = 'equals')
    {
        $this-&gt;expected = $object;
        $this-&gt;method   = $method;
    }

    public function toString(): string
    {
        return 'two objects are equal';
    }

    /**
     * @throws ActualValueIsNotAnObjectException
     * @throws ComparisonMethodDoesNotAcceptParameterTypeException
     * @throws ComparisonMethodDoesNotDeclareBoolReturnTypeException
     * @throws ComparisonMethodDoesNotDeclareExactlyOneParameterException
     * @throws ComparisonMethodDoesNotDeclareParameterTypeException
     * @throws ComparisonMethodDoesNotExistException
     */
    protected function matches($other): bool
    {
        if (!is_object($other)) {
            throw new ActualValueIsNotAnObjectException;
        }

        $object = new ReflectionObject($other);

        if (!$object-&gt;hasMethod($this-&gt;method)) {
            throw new ComparisonMethodDoesNotExistException(
                get_class($other),
                $this-&gt;method,
            );
        }

        /** @noinspection PhpUnhandledExceptionInspection */
        $method = $object-&gt;getMethod($this-&gt;method);

        if (!$method-&gt;hasReturnType()) {
            throw new ComparisonMethodDoesNotDeclareBoolReturnTypeException(
                get_class($other),
                $this-&gt;method,
            );
        }

        $returnType = $method-&gt;getReturnType();

        if (!$returnType instanceof ReflectionNamedType) {
            throw new ComparisonMethodDoesNotDeclareBoolReturnTypeException(
                get_class($other),
                $this-&gt;method,
            );
        }

        if ($returnType-&gt;allowsNull()) {
            throw new ComparisonMethodDoesNotDeclareBoolReturnTypeException(
                get_class($other),
                $this-&gt;method,
            );
        }

        if ($returnType-&gt;getName() !== 'bool') {
            throw new ComparisonMethodDoesNotDeclareBoolReturnTypeException(
                get_class($other),
                $this-&gt;method,
            );
        }

        if ($method-&gt;getNumberOfParameters() !== 1 || $method-&gt;getNumberOfRequiredParameters() !== 1) {
            throw new ComparisonMethodDoesNotDeclareExactlyOneParameterException(
                get_class($other),
                $this-&gt;method,
            );
        }

        $parameter = $method-&gt;getParameters()[0];

        if (!$parameter-&gt;hasType()) {
            throw new ComparisonMethodDoesNotDeclareParameterTypeException(
                get_class($other),
                $this-&gt;method,
            );
        }

        $type = $parameter-&gt;getType();

        if (!$type instanceof ReflectionNamedType) {
            throw new ComparisonMethodDoesNotDeclareParameterTypeException(
                get_class($other),
                $this-&gt;method,
            );
        }

        $typeName = $type-&gt;getName();

        if ($typeName === 'self') {
            $typeName = get_class($other);
        }

        if (!$this-&gt;expected instanceof $typeName) {
            throw new ComparisonMethodDoesNotAcceptParameterTypeException(
                get_class($other),
                $this-&gt;method,
                get_class($this-&gt;expected),
            );
        }

        return $other-&gt;{$this-&gt;method}($this-&gt;expected);
    }

    protected function failureDescription($other): string
    {
        return $this-&gt;toString();
    }
}
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