rector/rules/type-declaration/src/Rector/ClassMethod/ParamTypeFromStrictTypedPropertyRector.php

<?php

declare(strict_types=1);

namespace Rector\TypeDeclaration\Rector\ClassMethod;

use PhpParser\Node;
use PhpParser\Node\Expr\Assign;
use PhpParser\Node\Expr\PropertyFetch;
use PhpParser\Node\NullableType;
use PhpParser\Node\Param;
use PhpParser\Node\Stmt\ClassMethod;
use PhpParser\Node\Stmt\Property;
use PhpParser\Node\UnionType;
use PhpParser\NodeTraverser;
use PHPStan\Type\Type;
use Rector\Core\Rector\AbstractRector;
use Rector\Core\ValueObject\PhpVersionFeature;
use Symplify\Astral\NodeTraverser\SimpleCallableNodeTraverser;
use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;

/**
 * @see \Rector\TypeDeclaration\Tests\Rector\ClassMethod\ParamTypeFromStrictTypedPropertyRector\ParamTypeFromStrictTypedPropertyRectorTest
 */
final class ParamTypeFromStrictTypedPropertyRector extends AbstractRector
{
    /**
     * @var SimpleCallableNodeTraverser
     */
    private $simpleCallableNodeTraverser;

    public function __construct(SimpleCallableNodeTraverser $simpleCallableNodeTraverser)
    {
        $this->simpleCallableNodeTraverser = $simpleCallableNodeTraverser;
    }

    public function getRuleDefinition(): RuleDefinition
    {
        return new RuleDefinition('Add param type from $param set to typed property', [
            new CodeSample(
                <<<'CODE_SAMPLE'
final class SomeClass
{
    private int $age;

    public function setAge($age)
    {
        $this->age = $age;
    }
}
CODE_SAMPLE

                ,
                <<<'CODE_SAMPLE'
final class SomeClass
{
    private int $age;

    public function setAge(int $age)
    {
        $this->age = $age;
    }
}
CODE_SAMPLE

            ),
        ]);
    }

    /**
     * @return string[]
     */
    public function getNodeTypes(): array
    {
        return [ClassMethod::class];
    }

    /**
     * @param ClassMethod $node
     */
    public function refactor(Node $node): ?Node
    {
        if (! $this->isAtLeastPhpVersion(PhpVersionFeature::TYPED_PROPERTIES)) {
            return null;
        }

        foreach ($node->getParams() as $param) {
            $this->decorateParamWithType($node, $param);
        }

        return $node;
    }

    public function decorateParamWithType(ClassMethod $classMethod, Param $param): void
    {
        if ($param->type !== null) {
            return;
        }

        $this->simpleCallableNodeTraverser->traverseNodesWithCallable((array) $classMethod->stmts, function (
            Node $node
        ) use ($param): ?int {
            if (! $node instanceof Assign) {
                return null;
            }

            if (! $this->areNodesEqual($node->expr, $param)) {
                return null;
            }

            if (! $node->var instanceof PropertyFetch) {
                return null;
            }

            $property = $this->matchPropertyWithSingleType($node->var);
            if (! $property instanceof Property) {
                return null;
            }

            $param->type = $property->type;

            return NodeTraverser::STOP_TRAVERSAL;
        });
    }

    private function matchPropertyWithSingleType(PropertyFetch $propertyFetch): ?Property
    {
        $property = $this->nodeRepository->findPropertyByPropertyFetch($propertyFetch);
        if (! $property instanceof Property) {
            return null;
        }

        if ($property->type === null) {
            return null;
        }

        // move type to param if not union type
        if ($property->type instanceof UnionType) {
            return null;
        }

        if ($property->type instanceof NullableType) {
            return null;
        }

        return $property;
    }
}