Fix new NoConstructor purity

Author: ondrejmirtes

src/Analyser/NodeScopeResolver.php

@@ -3130,6 +3130,7 @@ static function (): void {
 				$className = $scope->resolveName($expr->class);
 			}
 
+			$classReflection = null;
 			if ($className !== null && $this->reflectionProvider->hasClass($className)) {
 				$classReflection = $this->reflectionProvider->getClass($className);
 				if ($classReflection->hasConstructor()) {
@@ -3160,7 +3161,7 @@ static function (): void {
 						$certain,
 					);
 				}
-			} else {
+			} elseif ($classReflection === null) {
 				$impurePoints[] = new ImpurePoint(
 					$scope,
 					$expr,

tests/PHPStan/Rules/Pure/data/pure-method.php

@@ -297,3 +297,23 @@ public function doFoo(
 	}
 
 }
+
+class NoConstructor
+{
+
+}
+
+class TestNoConstructor
+{
+
+	/**
+	 * @phpstan-pure
+	 */
+	public function doFoo(): int
+	{
+		new NoConstructor();
+
+		return 1;
+	}
+
+}