Assigning something other than $this in constructor is impure

phpstan · Apr 19, 2024 · c9f5b1c · c9f5b1c
1 parent 1ab6c28
commit c9f5b1c
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diff --git a/src/Analyser/NodeScopeResolver.php b/src/Analyser/NodeScopeResolver.php
@@ -655,6 +655,7 @@ private function processStmtNode(
 							&& $scope->getFunction() instanceof PhpMethodFromParserNodeReflection
 							&& $scope->getFunction()->getDeclaringClass()->hasConstructor()
 							&& $scope->getFunction()->getDeclaringClass()->getConstructor()->getName() === $scope->getFunction()->getName()
+							&& TypeUtils::findThisType($scope->getType($node->getPropertyFetch()->var)) !== null
 						) {
 							return;
 						}

diff --git a/tests/PHPStan/Rules/Pure/PureMethodRuleTest.php b/tests/PHPStan/Rules/Pure/PureMethodRuleTest.php
@@ -150,6 +150,10 @@ public function testPureConstructor(): void
 				'Method PureConstructor\Bar::__construct() is marked as impure but does not have any side effects.',
 				30,
 			],
+			[
+				'Impure property assignment in pure method PureConstructor\AssignOtherThanThis::__construct().',
+				49,
+			],
 		]);
 	}
 

diff --git a/tests/PHPStan/Rules/Pure/data/pure-constructor.php b/tests/PHPStan/Rules/Pure/data/pure-constructor.php
@@ -36,3 +36,16 @@ public function __construct(
 	}
 
 }
+
+class AssignOtherThanThis
+{
+	private int $i = 0;
+
+	/** @phpstan-pure */
+	public function __construct(
+		self $other,
+	)
+	{
+		$other->i = 1;
+	}
+}