hide fixed static parameter variance behind a feature toggle

Author: jiripudil

conf/bleedingEdge.neon

@@ -33,3 +33,4 @@ parameters:
 		instanceofType: true
 		paramOutVariance: true
 		allInvalidPhpDocs: true
+		strictStaticMethodTemplateTypeVariance: true

conf/config.neon

@@ -63,6 +63,7 @@ parameters:
 		instanceofType: false
 		paramOutVariance: false
 		allInvalidPhpDocs: false
+		strictStaticMethodTemplateTypeVariance: false
 	fileExtensions:
 		- php
 	checkAdvancedIsset: false
@@ -296,6 +297,7 @@ parametersSchema:
 		instanceofType: bool()
 		paramOutVariance: bool()
 		allInvalidPhpDocs: bool()
+		strictStaticMethodTemplateTypeVariance: bool()
 	])
 	fileExtensions: listOf(string())
 	checkAdvancedIsset: bool()
@@ -1050,6 +1052,7 @@ services:
 		class: PHPStan\Rules\Generics\VarianceCheck
 		arguments:
 			checkParamOutVariance: %featureToggles.paramOutVariance%
+			strictStaticVariance: %featureToggles.strictStaticMethodTemplateTypeVariance%
 
 	-
 		class: PHPStan\Rules\IssetCheck

src/Rules/Generics/FunctionSignatureVarianceRule.php

@@ -37,6 +37,7 @@ public function processNode(Node $node, Scope $scope): array
 			sprintf('in return type of function %s()', $functionName),
 			sprintf('in function %s()', $functionName),
 			false,
+			false,
 		);
 	}
 

src/Rules/Generics/MethodSignatureVarianceRule.php

@@ -35,6 +35,7 @@ public function processNode(Node $node, Scope $scope): array
 			sprintf('in param-out type of parameter %%s of method %s::%s()', SprintfHelper::escapeFormatString($method->getDeclaringClass()->getDisplayName()), SprintfHelper::escapeFormatString($method->getName())),
 			sprintf('in return type of method %s::%s()', $method->getDeclaringClass()->getDisplayName(), $method->getName()),
 			sprintf('in method %s::%s()', $method->getDeclaringClass()->getDisplayName(), $method->getName()),
+			$method->isStatic(),
 			$method->isPrivate() || $method->getName() === '__construct',
 		);
 	}

src/Rules/Generics/VarianceCheck.php

@@ -15,6 +15,7 @@ class VarianceCheck
 
 	public function __construct(
 		private bool $checkParamOutVariance,
+		private bool $strictStaticVariance,
 	)
 	{
 	}
@@ -26,6 +27,7 @@ public function checkParametersAcceptor(
 		string $parameterOutTypeMessage,
 		string $returnTypeMessage,
 		string $generalMessage,
+		bool $isStatic,
 		bool $isPrivate,
 	): array
 	{
@@ -51,7 +53,9 @@ public function checkParametersAcceptor(
 		}
 
 		$covariant = TemplateTypeVariance::createCovariant();
-		$parameterVariance = TemplateTypeVariance::createContravariant();
+		$parameterVariance = $isStatic && !$this->strictStaticVariance
+			? TemplateTypeVariance::createStatic()
+			: TemplateTypeVariance::createContravariant();
 
 		foreach ($parametersAcceptor->getParameters() as $parameterReflection) {
 			$type = $parameterReflection->getType();

tests/PHPStan/Rules/Generics/ClassAncestorsRuleTest.php

@@ -17,7 +17,7 @@ protected function getRule(): Rule
 			new GenericAncestorsCheck(
 				$this->createReflectionProvider(),
 				new GenericObjectTypeCheck(),
-				new VarianceCheck(true),
+				new VarianceCheck(true, true),
 				true,
 				[],
 			),

tests/PHPStan/Rules/Generics/EnumAncestorsRuleTest.php

@@ -18,7 +18,7 @@ protected function getRule(): Rule
 			new GenericAncestorsCheck(
 				$this->createReflectionProvider(),
 				new GenericObjectTypeCheck(),
-				new VarianceCheck(true),
+				new VarianceCheck(true, true),
 				true,
 				[],
 			),

tests/PHPStan/Rules/Generics/InterfaceAncestorsRuleTest.php

@@ -17,7 +17,7 @@ protected function getRule(): Rule
 			new GenericAncestorsCheck(
 				$this->createReflectionProvider(),
 				new GenericObjectTypeCheck(),
-				new VarianceCheck(true),
+				new VarianceCheck(true, true),
 				true,
 				[],
 			),

tests/PHPStan/Rules/Generics/UsedTraitsRuleTest.php

@@ -19,7 +19,7 @@ protected function getRule(): Rule
 			new GenericAncestorsCheck(
 				$this->createReflectionProvider(),
 				new GenericObjectTypeCheck(),
-				new VarianceCheck(true),
+				new VarianceCheck(true, true),
 				true,
 				[],
 			),