PossiblyPureMethodCallCollector - declaring class does not have to be final, but the callee class might

ondrejmirtes · ondrejmirtes · commit 024c32a5154e · 2024-04-18T13:23:25.000+02:00
diff --git a/src/Rules/DeadCode/PossiblyPureMethodCallCollector.php b/src/Rules/DeadCode/PossiblyPureMethodCallCollector.php
@@ -6,6 +6,7 @@
 use PhpParser\Node\Stmt\Expression;
 use PHPStan\Analyser\Scope;
 use PHPStan\Collectors\Collector;
+use function count;
 use function strtolower;
 
 /**
@@ -37,13 +38,21 @@ public function processNode(Node $node, Scope $scope)
 			return null;
 		}
 
-		$methodReflection = $scope->getMethodReflection($scope->getType($node->expr->var), $methodName);
+		$calledOnType = $scope->getType($node->expr->var);
+		$methodReflection = $scope->getMethodReflection($calledOnType, $methodName);
 		if ($methodReflection === null) {
 			return null;
 		}
 		if (!$methodReflection->isFinal()->yes()) {
 			if (!$methodReflection->getDeclaringClass()->isFinal()) {
-				return null;
+				$typeClassReflections = $calledOnType->getObjectClassReflections();
+				if (count($typeClassReflections) !== 1) {
+					return null;
+				}
+
+				if (!$typeClassReflections[0]->isFinal()) {
+					return null;
+				}
 			}
 		}
 		if (!$methodReflection->isPure()->maybe()) {
diff --git a/tests/PHPStan/Rules/DeadCode/CallToMethodStatementWithoutImpurePointsRuleTest.php b/tests/PHPStan/Rules/DeadCode/CallToMethodStatementWithoutImpurePointsRuleTest.php
@@ -35,6 +35,10 @@ public function testRule(): void
 				'Call to method CallToMethodWithoutImpurePoints\y::myFinalBaseFunc() on a separate line has no effect.',
 				36,
 			],
+			[
+				'Call to method CallToMethodWithoutImpurePoints\y::myFunc() on a separate line has no effect.',
+				39,
+			],
 			[
 				'Call to method CallToMethodWithoutImpurePoints\finalSubSubY::mySubSubFunc() on a separate line has no effect.',
 				40,
@@ -43,6 +47,10 @@ public function testRule(): void
 				'Call to method CallToMethodWithoutImpurePoints\y::myFinalBaseFunc() on a separate line has no effect.',
 				41,
 			],
+			[
+				'Call to method CallToMethodWithoutImpurePoints\AbstractFoo::myFunc() on a separate line has no effect.',
+				119,
+			],
 		]);
 	}
 
diff --git a/tests/PHPStan/Rules/DeadCode/data/call-to-method-without-impure-points.php b/tests/PHPStan/Rules/DeadCode/data/call-to-method-without-impure-points.php
@@ -101,3 +101,20 @@ function throwingFunc()
 		throw new \Exception();
 	}
 }
+
+abstract class AbstractFoo
+{
+
+	function myFunc()
+	{
+	}
+
+}
+final class FinalFoo extends AbstractFoo
+{
+
+}
+
+function (FinalFoo $foo): void {
+	$foo->myFunc();
+};
