Report impure methods overriding @pure-unless-parameter-passed methods

src/Rules/Methods/MethodSignatureRule.php

@@ -94,6 +94,18 @@ public function processNode(Node $node, Scope $scope): array
 					$parentMethodDeclaringClass->getDisplayName(),
 					$parentMethod->getName(),
 				))->identifier('method.impureOverridePureUnlessCallable')->build();
+			} elseif (
+				$this->reportMethodPurityOverride
+				&& $method->isPure()->no()
+				&& count($parentMethod->getPureUnlessParameterPassedParameters()) > 0
+			) {
+				$errors[] = RuleErrorBuilder::message(sprintf(
+					'Impure method %s::%s() overrides method %s::%s() marked @pure-unless-parameter-passed.',
+					$method->getDeclaringClass()->getDisplayName(),
+					$method->getName(),
+					$parentMethodDeclaringClass->getDisplayName(),
+					$parentMethod->getName(),
+				))->identifier('method.impureOverridePureUnlessParameterPassed')->build();
 			}
 
 			$parentVariants = $parentMethod->getVariants();

tests/PHPStan/Rules/Methods/MethodSignatureRuleTest.php

@@ -659,4 +659,21 @@ public function testPureUnlessCallableIsImpureOverride(): void
 		]);
 	}
 
+	public function testPureUnlessParameterPassedOverride(): void
+	{
+		$this->reportMaybes = true;
+		$this->reportStatic = true;
+		$this->reportMethodPurityOverride = true;
+		$this->analyse([__DIR__ . '/data/method-signature-pure-unless-parameter-passed.php'], [
+			[
+				'Impure method MethodSignaturePureUnlessParameterPassed\ImpureChild::replace() overrides method MethodSignaturePureUnlessParameterPassed\PureUnlessParent::replace() marked @pure-unless-parameter-passed.',
+				22,
+			],
+			[
+				'Impure method MethodSignaturePureUnlessParameterPassed\AllMethodsImpureChild::replace() overrides method MethodSignaturePureUnlessParameterPassed\PureUnlessParent::replace() marked @pure-unless-parameter-passed.',
+				76,
+			],
+		]);
+	}
+
 }

tests/PHPStan/Rules/Methods/data/method-signature-pure-unless-parameter-passed.php

@@ -0,0 +1,84 @@
+<?php declare(strict_types = 1);
+
+namespace MethodSignaturePureUnlessParameterPassed;
+
+interface PureUnlessParent
+{
+
+	/**
+	 * @param-out int $count
+	 * @pure-unless-parameter-passed $count
+	 */
+	public function replace(string $subject, int &$count = 0): string;
+
+}
+
+class ImpureChild implements PureUnlessParent
+{
+
+	/**
+	 * @phpstan-impure
+	 */
+	public function replace(string $subject, int &$count = 0): string
+	{
+		echo 'side effect';
+		$count = 1;
+
+		return $subject;
+	}
+
+}
+
+class InheritingChild implements PureUnlessParent
+{
+
+	public function replace(string $subject, int &$count = 0): string
+	{
+		$count = 1;
+
+		return $subject;
+	}
+
+}
+
+class PureChild implements PureUnlessParent
+{
+
+	/**
+	 * @phpstan-pure
+	 */
+	public function replace(string $subject, int &$count = 0): string
+	{
+		return $subject;
+	}
+
+}
+
+/**
+ * @phpstan-all-methods-pure
+ */
+class AllMethodsPureChild implements PureUnlessParent
+{
+
+	public function replace(string $subject, int &$count = 0): string
+	{
+		return $subject;
+	}
+
+}
+
+/**
+ * @phpstan-all-methods-impure
+ */
+class AllMethodsImpureChild implements PureUnlessParent
+{
+
+	public function replace(string $subject, int &$count = 0): string
+	{
+		echo 'side effect';
+		$count = 1;
+
+		return $subject;
+	}
+
+}