[DeadCode] Keep parent-delegating constructor when its docblock refines parameter types

rules-tests/DeadCode/Rector/ClassMethod/RemoveParentDelegatingConstructorRector/Fixture/skip_param_refining_docblock.php.inc

@@ -0,0 +1,26 @@
+<?php
+
+namespace Rector\Tests\DeadCode\Rector\ClassMethod\RemoveParentDelegatingConstructorRector\Fixture;
+
+class SomeScalarType
+{
+    public function __construct(array $config)
+    {
+    }
+}
+
+/**
+ * @phpstan-type CustomScalarConfig array{name?: string, serialize?: callable}
+ */
+class SomeRefiningScalarType extends SomeScalarType
+{
+    /**
+     * @param array<string, mixed> $config
+     *
+     * @phpstan-param CustomScalarConfig $config
+     */
+    public function __construct(array $config)
+    {
+        parent::__construct($config);
+    }
+}

rules/DeadCode/Rector/ClassMethod/RemoveParentDelegatingConstructorRector.php

@@ -16,6 +16,7 @@
 use PHPStan\BetterReflection\Reflection\Adapter\ReflectionParameter;
 use PHPStan\Reflection\ClassReflection;
 use PHPStan\Reflection\ExtendedMethodReflection;
+use Rector\BetterPhpDocParser\PhpDocInfo\PhpDocInfoFactory;
 use Rector\Enum\ObjectReference;
 use Rector\PhpParser\Node\Value\ValueResolver;
 use Rector\PHPStan\ScopeFetcher;
@@ -33,7 +34,8 @@ final class RemoveParentDelegatingConstructorRector extends AbstractRector
 {
     public function __construct(
         private readonly StaticTypeMapper $staticTypeMapper,
-        private readonly ValueResolver $valueResolver
+        private readonly ValueResolver $valueResolver,
+        private readonly PhpDocInfoFactory $phpDocInfoFactory
     ) {
     }
 
@@ -131,9 +133,23 @@ public function refactor(Node $node): ?int
             return null;
         }
 
+        // keep when the docblock refines parameter types beyond the native signature,
+        // e.g. @param array<string, mixed> or @phpstan-param SomeShape $config — removing
+        // the constructor would drop that type information
+        if ($this->hasParamRefiningDocblock($node)) {
+            return null;
+        }
+
         return NodeVisitor::REMOVE_NODE;
     }
 
+    private function hasParamRefiningDocblock(ClassMethod $classMethod): bool
+    {
+        $phpDocInfo = $this->phpDocInfoFactory->createFromNodeOrEmpty($classMethod);
+
+        return $phpDocInfo->hasByNames(['@param', '@phpstan-param', '@psalm-param']);
+    }
+
     private function matchParentConstructorReflection(ClassMethod $classMethod): ?ExtendedMethodReflection
     {
         $scope = ScopeFetcher::fetch($classMethod);