RemoveParentCallWithoutParentRector.php

<?php

declare(strict_types=1);

namespace Rector\DeadCode\Rector\StaticCall;

use PhpParser\Node;
use PhpParser\Node\Expr;
use PhpParser\Node\Expr\Assign;
use PhpParser\Node\Expr\StaticCall;
use PhpParser\Node\Name;
use PhpParser\Node\Name\FullyQualified;
use PhpParser\Node\Stmt\Class_;
use PhpParser\Node\Stmt\Expression;
use PHPStan\Reflection\ClassReflection;
use Rector\Enum\ObjectReference;
use Rector\NodeAnalyzer\ClassAnalyzer;
use Rector\NodeManipulator\ClassMethodManipulator;
use Rector\Rector\AbstractRector;
use Rector\Reflection\ClassReflectionAnalyzer;
use Rector\Reflection\ClassReflectionProvider;
use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;

/**
 * @see \Rector\Tests\DeadCode\Rector\StaticCall\RemoveParentCallWithoutParentRector\RemoveParentCallWithoutParentRectorTest
 */
final class RemoveParentCallWithoutParentRector extends AbstractRector
{
    public function __construct(
        private readonly ClassMethodManipulator $classMethodManipulator,
        private readonly ClassAnalyzer $classAnalyzer,
        private readonly ClassReflectionProvider $classReflectionProvider,
        private readonly ClassReflectionAnalyzer $classReflectionAnalyzer
    ) {
    }

    public function getRuleDefinition(): RuleDefinition
    {
        return new RuleDefinition(
            'Remove unused parent call with no parent class',
            [
                new CodeSample(
                    <<<'CODE_SAMPLE'
class OrphanClass
{
    public function __construct()
    {
         parent::__construct();
    }
}
CODE_SAMPLE
                    ,
                    <<<'CODE_SAMPLE'
class OrphanClass
{
    public function __construct()
    {
    }
}
CODE_SAMPLE
                ),
            ]
        );
    }

    /**
     * @return array<class-string<Node>>
     */
    public function getNodeTypes(): array
    {
        return [Class_::class];
    }

    /**
     * @param Class_ $node
     */
    public function refactor(Node $node): ?Node
    {
        if ($this->shouldSkipClass($node)) {
            return null;
        }

        $hasChanged = false;

        foreach ($node->getMethods() as $classMethod) {
            if ($classMethod->stmts === null) {
                continue;
            }

            foreach ($classMethod->stmts as $key => $stmt) {
                if (! $stmt instanceof Expression) {
                    continue;
                }

                if ($stmt->expr instanceof StaticCall && $this->isParentStaticCall($stmt->expr)) {
                    if ($this->doesCalledMethodExistInParent($stmt->expr, $node)) {
                        continue;
                    }

                    unset($classMethod->stmts[$key]);
                    $hasChanged = true;
                }

                if ($stmt->expr instanceof Assign) {
                    $assign = $stmt->expr;
                    if ($assign->expr instanceof StaticCall && $this->isParentStaticCall($assign->expr)) {
                        $staticCall = $assign->expr;

                        // is valid call
                        if ($this->doesCalledMethodExistInParent($staticCall, $node)) {
                            continue;
                        }

                        $assign->expr = $this->nodeFactory->createNull();
                        $hasChanged = true;
                    }
                }
            }
        }

        if ($hasChanged) {
            return $node;
        }

        return null;
    }

    private function isParentStaticCall(Expr $expr): bool
    {
        if (! $expr instanceof StaticCall) {
            return false;
        }

        if ($expr->name instanceof Expr) {
            return false;
        }

        return $this->isName($expr->class, ObjectReference::PARENT);
    }

    private function shouldSkipClass(Class_ $class): bool
    {
        // skip cases when parent class reflection is not found
        if ($class->extends instanceof FullyQualified && ! $this->classReflectionProvider->hasClass(
            $class->extends->toString()
        )) {
            return true;
        }

        // currently the classMethodManipulator isn't able to find usages of anonymous classes
        return $this->classAnalyzer->isAnonymousClass($class);
    }

    private function doesCalledMethodExistInParent(StaticCall $staticCall, Class_ $class): bool
    {
        if (! $class->extends instanceof Name) {
            return false;
        }

        $calledMethodName = $this->getName($staticCall->name);
        if (! is_string($calledMethodName)) {
            return false;
        }

        if ($this->classMethodManipulator->hasParentMethodOrInterfaceMethod($class, $calledMethodName)) {
            return true;
        }

        // the called method may be defined in an ancestor that cannot be resolved
        // (e.g. a grandparent class is not autoloadable); in that case we cannot
        // safely tell the method does not exist, so the call must not be removed
        return $this->hasUnresolvableAncestor($class->extends);
    }

    private function hasUnresolvableAncestor(Name $parentName): bool
    {
        $parentClassName = $this->getName($parentName);
        if (! is_string($parentClassName)) {
            return false;
        }

        if (! $this->classReflectionProvider->hasClass($parentClassName)) {
            return true;
        }

        $parentClassReflection = $this->classReflectionProvider->getClass($parentClassName);

        return $this->hasUnresolvableParentClass($parentClassReflection);
    }

    private function hasUnresolvableParentClass(ClassReflection $classReflection): bool
    {
        $parentClassName = $this->classReflectionAnalyzer->resolveParentClassName($classReflection);
        if ($parentClassName === null) {
            return false;
        }

        $parentClassReflection = $classReflection->getParentClass();
        if (! $parentClassReflection instanceof ClassReflection) {
            return true;
        }

        return $this->hasUnresolvableParentClass($parentClassReflection);
    }
}