rector/rules/TypeDeclaration/Rector/Param/ParamTypeFromStrictTypedPropertyRector.php

<?php

declare(strict_types=1);

namespace Rector\TypeDeclaration\Rector\Param;

use PhpParser\Node;
use PhpParser\Node\Expr\Assign;
use PhpParser\Node\Expr\PropertyFetch;
use PhpParser\Node\FunctionLike;
use PhpParser\Node\NullableType;
use PhpParser\Node\Param;
use PhpParser\Node\Stmt\Property;
use PhpParser\Node\UnionType;
use PHPStan\Analyser\Scope;
use PHPStan\Type\MixedType;
use PHPStan\Type\Type;
use Rector\Core\Rector\AbstractRector;
use Rector\Core\ValueObject\PhpVersionFeature;
use Rector\NodeTypeResolver\Node\AttributeKey;
use Rector\TypeDeclaration\Reflection\ReflectionTypeResolver;
use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;

/**
 * @see \Rector\Tests\TypeDeclaration\Rector\Param\ParamTypeFromStrictTypedPropertyRector\ParamTypeFromStrictTypedPropertyRectorTest
 */
final class ParamTypeFromStrictTypedPropertyRector extends AbstractRector
{
    /**
     * @var ReflectionTypeResolver
     */
    private $reflectionTypeResolver;

    public function __construct(ReflectionTypeResolver $reflectionTypeResolver)
    {
        $this->reflectionTypeResolver = $reflectionTypeResolver;
    }

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

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

        $parent = $node->getAttribute(AttributeKey::PARENT_NODE);
        if (! $parent instanceof FunctionLike) {
            return null;
        }

        return $this->decorateParamWithType($parent, $node);
    }

    public function decorateParamWithType(FunctionLike $functionLike, Param $param): ?Param
    {
        if ($param->type !== null) {
            return null;
        }

        $originalParamType = $this->resolveParamOriginalType($param);

        $paramName = $this->getName($param);

        /** @var Assign[] $assigns */
        $assigns = $this->betterNodeFinder->findInstanceOf((array) $functionLike->getStmts(), Assign::class);
        foreach ($assigns as $assign) {
            if (! $this->nodeComparator->areNodesEqual($assign->expr, $param->var)) {
                continue;
            }

            if (! $assign->var instanceof PropertyFetch) {
                continue;
            }

            if ($this->hasTypeChangedBeforeAssign($assign, $paramName, $originalParamType)) {
                return null;
            }

            $singlePropertyTypeNode = $this->matchPropertySingleTypeNode($assign->var);
            if (! $singlePropertyTypeNode instanceof Node) {
                return null;
            }

            $param->type = $singlePropertyTypeNode;
            return $param;
        }

        return null;
    }

    /**
     * @return Node\Identifier|Node\Name|UnionType|NullableType|null
     */
    private function matchPropertySingleTypeNode(PropertyFetch $propertyFetch): ?Node
    {
        $property = $this->nodeRepository->findPropertyByPropertyFetch($propertyFetch);
        if (! $property instanceof Property) {
            // code from /vendor
            $propertyFetchType = $this->reflectionTypeResolver->resolvePropertyFetchType($propertyFetch);
            if (! $propertyFetchType instanceof Type) {
                return null;
            }

            return $this->staticTypeMapper->mapPHPStanTypeToPhpParserNode($propertyFetchType);
        }

        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;
        }

        // needed to avoid reprinting original tokens bug
        $typeNode = clone $property->type;
        $typeNode->setAttribute(AttributeKey::ORIGINAL_NODE, null);

        return $typeNode;
    }

    private function hasTypeChangedBeforeAssign(Assign $assign, string $paramName, Type $originalType): bool
    {
        $scope = $assign->getAttribute(AttributeKey::SCOPE);
        if (! $scope instanceof Scope) {
            return false;
        }

        if (! $scope->hasVariableType($paramName)->yes()) {
            return false;
        }

        $currentParamType = $scope->getVariableType($paramName);
        return ! $currentParamType->equals($originalType);
    }

    private function resolveParamOriginalType(Param $param): Type
    {
        $scope = $param->getAttribute(AttributeKey::SCOPE);
        if (! $scope instanceof Scope) {
            return new MixedType();
        }

        $paramName = $this->getName($param);
        if (! $scope->hasVariableType($paramName)->yes()) {
            return new MixedType();
        }

        return $scope->getVariableType($paramName);
    }
}