Go\Instrument\Transformer\ConstructorExecutionTransformer

Complexity

Total Complexity

25

Size/Duplication

Total Lines	139
Duplicated Lines	0 %

Coupling/Cohesion

Components	1
Dependencies	2

Test Coverage

Coverage

97.14%

Importance

Changes

0

5 Methods

Rating	Name	Duplication	Size	Complexity
A	getInstance()	0	9	2
C	transform()	0	49	16
A	__get()	0	4	1
A	__call()	0	4	1
B	construct()	0	24	5

<?php
declare(strict_types = 1);
/*
 * Go! AOP framework
 *
 * @copyright Copyright 2014, Lisachenko Alexander <lisachenko.it@gmail.com>
 *
 * This source file is subject to the license that is bundled
 * with this source code in the file LICENSE.
 */

namespace Go\Instrument\Transformer;

use Go\Aop\Framework\ReflectionConstructorInvocation;
use Go\Core\AspectContainer;

/**
 * Transforms the source code to add an ability to intercept new instances creation
 *
 * @see https://github.com/php/php-src/blob/master/Zend/zend_language_parser.y
 *
 * new_expr:
 *   T_NEW
 *   class_name_reference
 *   ctor_arguments
 *
 * class_name_reference:
 *   class_name
 *   | new_variable
 *
 * class_name:
 *   T_STATIC
 *   | name
 *
 * namespace_name:
 *   T_STRING
 *   | namespace_name T_NS_SEPARATOR T_STRING
 *
 * name:
 *   namespace_name
 *   | T_NAMESPACE T_NS_SEPARATOR namespace_name
 *   | T_NS_SEPARATOR namespace_name
 *
 * ctor_arguments:
 *   / empty /
 *   | argument_list
 */
class ConstructorExecutionTransformer implements SourceTransformer
{
    /**
     * List of constructor invocations per class
     *
     * @var array|ReflectionConstructorInvocation[]
     */
    private static $constructorInvocationsCache = [];

    /**
     * Singletone
     *
     * @return static
     */
    public static function getInstance()
    {
        static $instance;
        if (!$instance) {
            $instance = new static;
        }

        return $instance;
    }

    /**
     * Rewrites all "new" expressions with our implementation
     *
     * @param StreamMetaData $metadata Metadata for source
     *
     * @return string See RESULT_XXX constants in the interface
     */
    public function transform(StreamMetaData $metadata): string
    {
        if (strpos($metadata->source, 'new ') === false) {
            return self::RESULT_ABSTAIN;
        }

        $tokenStream       = token_get_all($metadata->source);
        $transformedSource = '';
        $isWaitingClass    = false;
        $isWaitingEnd      = false;
        $isClassName       = true;
        $classNamePosition = 0;
        $weavingResult     = self::RESULT_ABSTAIN;
        foreach ($tokenStream as $index=>$token) {

Expected 1 space before "=>"; 0 found

Expected 1 space after "=>"; 0 found

            list ($token, $tokenValue) = (array) $token + [1 => $token];
            if ($isWaitingClass && $token !== T_WHITESPACE && $token !== T_COMMENT) {
                $classNamePosition++;
                if ($token === T_VARIABLE && $classNamePosition === 1) {
                    $isWaitingEnd   = true;
                    $isWaitingClass = false;
                }
                if (in_array($tokenStream[$index + 1], ['(', ';', ')', '.'])) {
                    $isWaitingEnd   = true;
                    $isWaitingClass = false;
                }
                if ($isClassName && $token !== T_NS_SEPARATOR && $token !== T_STRING && $token !== T_STATIC) {
                    $isClassName = false;
                }
            }
            if ($token === T_NEW) {
                $tokenValue = '\\' . __CLASS__ . '::getInstance()->{';
                $isWaitingClass = true;
                $isClassName    = true;

                $classNamePosition = 0;
                $weavingResult     = self::RESULT_TRANSFORMED;
            }
            $transformedSource .= $tokenValue;

            if ($isWaitingEnd) {
                $transformedSource .= $isClassName ? '::class' : '';
                $transformedSource .= '}';
                $isWaitingEnd = false;
            }
        }
        $metadata->source = $transformedSource;

        return $weavingResult;
    }

    /**
     * Magic interceptor for instance creation
     *
     * @param string $className Name of the class to construct
     *
     * @return object Instance of required object
     */
    public function __get($className)
    {
        return static::construct($className);
    }

    /**
     * Magic interceptor for instance creation
     *
     * @param string $className Name of the class to construct
     * @param array $args Arguments for the constructor
     *
     * @return object Instance of required object
     */
    public function __call($className, array $args)
    {
        return static::construct($className, $args);
    }

    /**
     * Default implementation for accessing joinpoint or creating a new one on-fly
     *
     * @param string $fullClassName Name of the class to create
     * @param array $arguments Arguments for constructor
     *
     * @return object
     */
    protected static function construct($fullClassName, array $arguments = [])
    {
        $fullClassName = ltrim($fullClassName, '\\');
        if (!isset(self::$constructorInvocationsCache[$fullClassName])) {
            $invocation = null;
            $dynamicInit = AspectContainer::INIT_PREFIX . ':root';
            try {
                $joinPointsRef = new \ReflectionProperty($fullClassName, '__joinPoints');
                $joinPointsRef->setAccessible(true);
                $joinPoints = $joinPointsRef->getValue();
                if (isset($joinPoints[$dynamicInit])) {
                    $invocation = $joinPoints[$dynamicInit];
                }
            } catch (\ReflectionException $e) {
                $invocation = null;
            }
            if (!$invocation) {
                $invocation = new ReflectionConstructorInvocation($fullClassName, 'root', []);
            }
            self::$constructorInvocationsCache[$fullClassName] = $invocation;
        }

        return self::$constructorInvocationsCache[$fullClassName]->__invoke($arguments);
    }
}