Bleeding edge - assign by ref - use parameter type when @param-out is not present

Author: ondrejmirtes

conf/config.neon

@@ -495,6 +495,7 @@ services:
 			treatPhpDocTypesAsCertain: %treatPhpDocTypesAsCertain%
 			detectDeadTypeInMultiCatch: %featureToggles.detectDeadTypeInMultiCatch%
 			universalObjectCratesClasses: %universalObjectCratesClasses%
+			paramOutType: %featureToggles.paramOutType%
 
 	-
 		class: PHPStan\Analyser\ConstantResolver

src/Analyser/NodeScopeResolver.php

@@ -243,6 +243,7 @@ public function __construct(
 		private readonly bool $implicitThrows,
 		private readonly bool $treatPhpDocTypesAsCertain,
 		private readonly bool $detectDeadTypeInMultiCatch,
+		private readonly bool $paramOutType,
 	)
 	{
 		$earlyTerminatingMethodNames = [];
@@ -3863,12 +3864,36 @@ private function processArgs(
 				$assignByReference = $parameters[$i]->passedByReference()->createsNewVariable();
 				if ($parameters[$i] instanceof ParameterReflectionWithPhpDocs && $parameters[$i]->getOutType() !== null) {
 					$byRefType = $parameters[$i]->getOutType();
+				} elseif (
+					$calleeReflection instanceof MethodReflection
+					&& !$calleeReflection->getDeclaringClass()->isBuiltin()
+					&& $this->paramOutType
+				) {
+					$byRefType = $parameters[$i]->getType();
+				} elseif (
+					$calleeReflection instanceof FunctionReflection
+					&& !$calleeReflection->isBuiltin()
+					&& $this->paramOutType
+				) {
+					$byRefType = $parameters[$i]->getType();
 				}
 			} elseif (count($parameters) > 0 && $parametersAcceptor->isVariadic()) {
 				$lastParameter = $parameters[count($parameters) - 1];
 				$assignByReference = $lastParameter->passedByReference()->createsNewVariable();
 				if ($lastParameter instanceof ParameterReflectionWithPhpDocs && $lastParameter->getOutType() !== null) {
 					$byRefType = $lastParameter->getOutType();
+				} elseif (
+					$calleeReflection instanceof MethodReflection
+					&& !$calleeReflection->getDeclaringClass()->isBuiltin()
+					&& $this->paramOutType
+				) {
+					$byRefType = $lastParameter->getType();
+				} elseif (
+					$calleeReflection instanceof FunctionReflection
+					&& !$calleeReflection->isBuiltin()
+					&& $this->paramOutType
+				) {
+					$byRefType = $lastParameter->getType();
 				}
 			}
 

src/Testing/RuleTestCase.php

@@ -103,6 +103,7 @@ private function getAnalyser(): Analyser
 				self::getContainer()->getParameter('exceptions')['implicitThrows'],
 				$this->shouldTreatPhpDocTypesAsCertain(),
 				self::getContainer()->getParameter('featureToggles')['detectDeadTypeInMultiCatch'],
+				self::getContainer()->getParameter('featureToggles')['paramOutType'],
 			);
 			$fileAnalyser = new FileAnalyser(
 				$this->createScopeFactory($reflectionProvider, $typeSpecifier),

src/Testing/TypeInferenceTestCase.php

@@ -70,6 +70,7 @@ public static function processFile(
 			true,
 			self::getContainer()->getParameter('treatPhpDocTypesAsCertain'),
 			self::getContainer()->getParameter('featureToggles')['detectDeadTypeInMultiCatch'],
+			self::getContainer()->getParameter('featureToggles')['paramOutType'],
 		);
 		$resolver->setAnalysedFiles(array_map(static fn (string $file): string => $fileHelper->normalizePath($file), array_merge([$file], static::getAdditionalAnalysedFiles())));
 

tests/PHPStan/Analyser/AnalyserTest.php

@@ -663,6 +663,7 @@ private function createAnalyser(bool $reportUnmatchedIgnoredErrors, bool $enable
 			true,
 			$this->shouldTreatPhpDocTypesAsCertain(),
 			self::getContainer()->getParameter('featureToggles')['detectDeadTypeInMultiCatch'],
+			self::getContainer()->getParameter('featureToggles')['paramOutType'],
 		);
 		$lexer = new Lexer(['usedAttributes' => ['comments', 'startLine', 'endLine', 'startTokenPos', 'endTokenPos']]);
 		$fileAnalyser = new FileAnalyser(

tests/PHPStan/Analyser/LegacyNodeScopeResolverTest.php

@@ -7965,7 +7965,7 @@ public function dataPassedByReference(): array
 				'$matches',
 			],
 			[
-				'mixed',
+				'string',
 				'$s',
 			],
 		];

tests/PHPStan/Analyser/data/param-out.php

@@ -446,3 +446,58 @@ function fooIsCallable($x, bool $b)
 	is_callable($x, $b, $name);
 	assertType('callable-string', $name);
 }
+
+function noParamOut(string &$s): void
+{
+
+}
+
+function noParamOutVariadic(string &...$s): void
+{
+
+}
+
+function ($s): void {
+	assertType('mixed', $s);
+	noParamOut($s);
+	assertType('string', $s);
+};
+
+function ($s, $t): void {
+	assertType('mixed', $s);
+	assertType('mixed', $t);
+	noParamOutVariadic($s, $t);
+	assertType('string', $s);
+	assertType('string', $t);
+};
+
+class NoParamOutClass
+{
+
+	function doFoo(string &$s): void
+	{
+
+	}
+
+	function doFooVariadic(string &...$s): void
+	{
+
+	}
+
+}
+
+function ($s): void {
+	assertType('mixed', $s);
+	$c = new NoParamOutClass();
+	$c->doFoo($s);
+	assertType('string', $s);
+};
+
+function ($s, $t): void {
+	assertType('mixed', $s);
+	assertType('mixed', $t);
+	$c = new NoParamOutClass();
+	$c->doFooVariadic($s, $t);
+	assertType('string', $s);
+	assertType('string', $t);
+};