Fix AccessPropertiesCheck for checkThisOnly

src/Rules/Properties/AccessPropertiesCheck.php

@@ -42,6 +42,8 @@ public function __construct(
 		private bool $checkDynamicProperties,
 		#[AutowiredParameter(ref: '%featureToggles.checkNonStringableDynamicAccess%')]
 		private bool $checkNonStringableDynamicAccess,
+		#[AutowiredParameter]
+		private bool $checkThisOnly,
 	)
 	{
 	}
@@ -58,20 +60,7 @@ public function check(PropertyFetch $node, Scope $scope, bool $write): array
 			$names = array_map(static fn (ConstantStringType $type): string => $type->getValue(), $scope->getType($node->name)->getConstantStrings());
 
 			if (!$write && $this->checkNonStringableDynamicAccess) {
-				$nameTypeResult = $this->ruleLevelHelper->findTypeToCheck(
-					$scope,
-					$node->name,
-					'',
-					static fn (Type $type) => $type->toString()->isString()->yes(),
-				);
-				$nameType = $nameTypeResult->getType();
-				if ($nameType instanceof ErrorType || $nameType->toString() instanceof ErrorType || !$nameType->toString()->isString()->yes()) {
-					$originalNameType = $scope->getType($node->name);
-					$className = $scope->getType($node->var)->describe(VerbosityLevel::typeOnly());
-					$errors[] = RuleErrorBuilder::message(sprintf('Property name for %s must be a string, but %s was given.', $className, $originalNameType->describe(VerbosityLevel::precise())))
-						->identifier('property.nameNotString')
-						->build();
-				}
+				$errors = array_merge($errors, $this->checkNonStringableDynamicAccess($scope, $node->var, $node->name));
 			}
 		}
 
@@ -82,6 +71,44 @@ public function check(PropertyFetch $node, Scope $scope, bool $write): array
 		return $errors;
 	}
 
+	/**
+	 * @return list<IdentifierRuleError>
+	 */
+	private function checkNonStringableDynamicAccess(Scope $scope, Expr $nodeVar, Expr $nodeName): array
+	{
+		if (
+			$this->checkThisOnly
+			&& !$this->ruleLevelHelper->isThis($nodeVar)
+		) {
+			return [];
+		}
+
+		$nameTypeResult = $this->ruleLevelHelper->findTypeToCheck(
+			$scope,
+			$nodeName,
+			'',
+			static fn (Type $type) => $type->toString()->isString()->yes(),
+		);
+		$nameType = $nameTypeResult->getType();
+		if (
+			!$nameType instanceof ErrorType
+			&& !$nameType->toString() instanceof ErrorType
+			&& $nameType->toString()->isString()->yes()
+		) {
+			return [];
+		}
+
+		$originalNameType = $scope->getType($nodeName);
+		$className = $scope->getType($nodeVar)->describe(VerbosityLevel::typeOnly());
+		return [
+			RuleErrorBuilder::message(sprintf(
+				'Property name for %s must be a string, but %s was given.',
+				$className,
+				$originalNameType->describe(VerbosityLevel::precise()),
+			))->identifier('property.nameNotString')->build(),
+		];
+	}
+
 	/**
 	 * @return list<IdentifierRuleError>
 	 */

tests/PHPStan/Rules/Properties/AccessPropertiesInAssignRuleTest.php

@@ -19,7 +19,15 @@ protected function getRule(): Rule
 	{
 		$reflectionProvider = self::createReflectionProvider();
 		return new AccessPropertiesInAssignRule(
-			new AccessPropertiesCheck($reflectionProvider, new RuleLevelHelper($reflectionProvider, true, false, true, false, false, false, true), new PhpVersion(PHP_VERSION_ID), true, true, true),
+			new AccessPropertiesCheck(
+				$reflectionProvider,
+				new RuleLevelHelper($reflectionProvider, true, false, true, false, false, false, true),
+				new PhpVersion(PHP_VERSION_ID),
+				true,
+				true,
+				true,
+				false,
+			),
 		);
 	}
 

tests/PHPStan/Rules/Properties/AccessPropertiesRuleTest.php

@@ -26,7 +26,15 @@ class AccessPropertiesRuleTest extends RuleTestCase
 	protected function getRule(): Rule
 	{
 		$reflectionProvider = self::createReflectionProvider();
-		return new AccessPropertiesRule(new AccessPropertiesCheck($reflectionProvider, new RuleLevelHelper($reflectionProvider, true, $this->checkThisOnly, $this->checkUnionTypes, false, false, false, true), new PhpVersion(PHP_VERSION_ID), true, $this->checkDynamicProperties, true));
+		return new AccessPropertiesRule(new AccessPropertiesCheck(
+			$reflectionProvider,
+			new RuleLevelHelper($reflectionProvider, true, $this->checkThisOnly, $this->checkUnionTypes, false, false, false, true),
+			new PhpVersion(PHP_VERSION_ID),
+			true,
+			$this->checkDynamicProperties,
+			true,
+			$this->checkThisOnly,
+		));
 	}
 
 	public function testAccessProperties(): void
@@ -1092,6 +1100,14 @@ public function testNewIsAlwaysFinalClass(): void
 		]);
 	}
 
+	public function testBug13271(): void
+	{
+		$this->checkThisOnly = true;
+		$this->checkUnionTypes = false;
+		$this->checkDynamicProperties = true;
+		$this->analyse([__DIR__ . '/data/bug-13271.php'], []);
+	}
+
 	public function testPropertyExists(): void
 	{
 		$this->checkThisOnly = false;

tests/PHPStan/Rules/Properties/data/bug-13271.php

@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace Bug13271;
+
+$object = new class{
+	public string $example_one = "";
+	public string $example_two = "";
+};
+
+$field = rand() > 0.5 ? 'example_one' : 'example_two';
+$result = $object->$field;