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    <h3>Editing: Invocation.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\MockObject;

use function array_map;
use function explode;
use function get_class;
use function implode;
use function in_array;
use function interface_exists;
use function is_object;
use function sprintf;
use function strpos;
use function strtolower;
use function substr;
use Doctrine\Instantiator\Instantiator;
use PHPUnit\Framework\SelfDescribing;
use PHPUnit\Util\Cloner;
use SebastianBergmann\Exporter\Exporter;
use stdClass;
use Throwable;

/**
 * @internal This class is not covered by the backward compatibility promise for PHPUnit
 */
final class Invocation implements SelfDescribing
{
    /**
     * @var string
     */
    private $className;

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

    /**
     * @var array
     */
    private $parameters;

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

    /**
     * @var bool
     */
    private $isReturnTypeNullable = false;

    /**
     * @var bool
     */
    private $proxiedCall;

    /**
     * @var object
     */
    private $object;

    public function __construct(string $className, string $methodName, array $parameters, string $returnType, object $object, bool $cloneObjects = false, bool $proxiedCall = false)
    {
        $this-&gt;className   = $className;
        $this-&gt;methodName  = $methodName;
        $this-&gt;parameters  = $parameters;
        $this-&gt;object      = $object;
        $this-&gt;proxiedCall = $proxiedCall;

        if (strtolower($methodName) === '__tostring') {
            $returnType = 'string';
        }

        if (strpos($returnType, '?') === 0) {
            $returnType                 = substr($returnType, 1);
            $this-&gt;isReturnTypeNullable = true;
        }

        $this-&gt;returnType = $returnType;

        if (!$cloneObjects) {
            return;
        }

        foreach ($this-&gt;parameters as $key =&gt; $value) {
            if (is_object($value)) {
                $this-&gt;parameters[$key] = Cloner::clone($value);
            }
        }
    }

    public function getClassName(): string
    {
        return $this-&gt;className;
    }

    public function getMethodName(): string
    {
        return $this-&gt;methodName;
    }

    public function getParameters(): array
    {
        return $this-&gt;parameters;
    }

    /**
     * @throws RuntimeException
     *
     * @return mixed Mocked return value
     */
    public function generateReturnValue()
    {
        if ($this-&gt;isReturnTypeNullable || $this-&gt;proxiedCall) {
            return null;
        }

        $intersection               = false;
        $union                      = false;
        $unionContainsIntersections = false;

        if (strpos($this-&gt;returnType, '|') !== false) {
            $types = explode('|', $this-&gt;returnType);
            $union = true;

            if (strpos($this-&gt;returnType, '(') !== false) {
                $unionContainsIntersections = true;
            }
        } elseif (strpos($this-&gt;returnType, '&amp;') !== false) {
            $types        = explode('&amp;', $this-&gt;returnType);
            $intersection = true;
        } else {
            $types = [$this-&gt;returnType];
        }

        $types = array_map('strtolower', $types);

        if (!$intersection &amp;&amp; !$unionContainsIntersections) {
            if (in_array('', $types, true) ||
                in_array('null', $types, true) ||
                in_array('mixed', $types, true) ||
                in_array('void', $types, true)) {
                return null;
            }

            if (in_array('true', $types, true)) {
                return true;
            }

            if (in_array('false', $types, true) ||
                in_array('bool', $types, true)) {
                return false;
            }

            if (in_array('float', $types, true)) {
                return 0.0;
            }

            if (in_array('int', $types, true)) {
                return 0;
            }

            if (in_array('string', $types, true)) {
                return '';
            }

            if (in_array('array', $types, true)) {
                return [];
            }

            if (in_array('static', $types, true)) {
                try {
                    return (new Instantiator)-&gt;instantiate(get_class($this-&gt;object));
                } catch (Throwable $t) {
                    throw new RuntimeException(
                        $t-&gt;getMessage(),
                        (int) $t-&gt;getCode(),
                        $t,
                    );
                }
            }

            if (in_array('object', $types, true)) {
                return new stdClass;
            }

            if (in_array('callable', $types, true) ||
                in_array('closure', $types, true)) {
                return static function (): void
                {
                };
            }

            if (in_array('traversable', $types, true) ||
                in_array('generator', $types, true) ||
                in_array('iterable', $types, true)) {
                $generator = static function (): \Generator
                {
                    yield from [];
                };

                return $generator();
            }

            if (!$union) {
                try {
                    return (new Generator)-&gt;getMock($this-&gt;returnType, [], [], '', false);
                } catch (Throwable $t) {
                    if ($t instanceof Exception) {
                        throw $t;
                    }

                    throw new RuntimeException(
                        $t-&gt;getMessage(),
                        (int) $t-&gt;getCode(),
                        $t,
                    );
                }
            }
        }

        if ($intersection &amp;&amp; $this-&gt;onlyInterfaces($types)) {
            try {
                return (new Generator)-&gt;getMockForInterfaces($types);
            } catch (Throwable $t) {
                throw new RuntimeException(
                    sprintf(
                        'Return value for %s::%s() cannot be generated: %s',
                        $this-&gt;className,
                        $this-&gt;methodName,
                        $t-&gt;getMessage(),
                    ),
                    (int) $t-&gt;getCode(),
                );
            }
        }

        $reason = '';

        if ($union) {
            $reason = ' because the declared return type is a union';
        } elseif ($intersection) {
            $reason = ' because the declared return type is an intersection';
        }

        throw new RuntimeException(
            sprintf(
                'Return value for %s::%s() cannot be generated%s, please configure a return value for this method',
                $this-&gt;className,
                $this-&gt;methodName,
                $reason,
            ),
        );
    }

    public function toString(): string
    {
        $exporter = new Exporter;

        return sprintf(
            '%s::%s(%s)%s',
            $this-&gt;className,
            $this-&gt;methodName,
            implode(
                ', ',
                array_map(
                    [$exporter, 'shortenedExport'],
                    $this-&gt;parameters,
                ),
            ),
            $this-&gt;returnType ? sprintf(': %s', $this-&gt;returnType) : '',
        );
    }

    public function getObject(): object
    {
        return $this-&gt;object;
    }

    /**
     * @psalm-param non-empty-list&lt;string&gt; $types
     */
    private function onlyInterfaces(array $types): bool
    {
        foreach ($types as $type) {
            if (!interface_exists($type)) {
                return false;
            }
        }

        return true;
    }
}
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