Fix unused private property is not sometimes detected

Author: staabm

src/Rules/DeadCode/UnusedPrivatePropertyRule.php

@@ -120,7 +120,7 @@ public function processNode(Node $node, Scope $scope): array
 				$propertyNameType = $usage->getScope()->getType($fetch->name);
 				$strings = $propertyNameType->getConstantStrings();
 				if (count($strings) === 0) {
-					return [];
+					continue;
 				}
 
 				$propertyNames = array_map(static fn (ConstantStringType $type): string => $type->getValue(), $strings);

tests/PHPStan/Rules/DeadCode/UnusedPrivatePropertyRuleTest.php

@@ -107,6 +107,11 @@ public function testRule(): void
 				117,
 				$tip,
 			],
+			[
+				'Property UnusedPrivateProperty\Ipsum::$foo is never read, only written.',
+				136,
+				$tip,
+			],
 			[
 				'Property class@anonymous/tests/PHPStan/Rules/DeadCode/data/unused-private-property.php:152::$bar is unused.',
 				153,
@@ -336,4 +341,19 @@ public function testBug7251(): void
 		$this->analyse([__DIR__ . '/data/bug-7251.php'], []);
 	}
 
+	public function testBug11802(): void
+	{
+		$tip = 'See: https://phpstan.org/developing-extensions/always-read-written-properties';
+
+		$this->alwaysWrittenTags = [];
+		$this->alwaysReadTags = [];
+		$this->analyse([__DIR__ . '/data/bug-11802.php'], [
+			[
+				'Property Bug11802\HelloWorld::$isFinal is never read, only written.',
+				8,
+				$tip,
+			],
+		]);
+	}
+
 }

tests/PHPStan/Rules/DeadCode/data/bug-11802.php

@@ -0,0 +1,17 @@
+<?php declare(strict_types=1);
+
+namespace Bug11802;
+
+class HelloWorld
+{
+	public function __construct(
+		private bool $isFinal
+	)
+	{
+	}
+
+	public function doFoo(HelloWorld $x, string $y): void
+	{
+		$s = $x->{$y()};
+	}
+}