Avoid false positif for namespaced Xpath

Author: VincentLanglet

src/Type/Php/SimpleXMLElementXpathMethodReturnTypeExtension.php

@@ -7,7 +7,6 @@
 use PHPStan\Reflection\MethodReflection;
 use PHPStan\Reflection\ParametersAcceptorSelector;
 use PHPStan\Type\ArrayType;
-use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\MixedType;
 use PHPStan\Type\NeverType;
 use PHPStan\Type\Type;
@@ -37,26 +36,20 @@ public function getTypeFromMethodCall(MethodReflection $methodReflection, Method
 
 		$xmlElement = new \SimpleXMLElement('<foo />');
 
-		$result = null;
 		foreach (TypeUtils::getConstantStrings($argType) as $constantString) {
-			$newResult = @$xmlElement->xpath($constantString->getValue());
-
-			if ($result !== null && gettype($result) !== gettype($newResult)) {
+			$result = @$xmlElement->xpath($constantString->getValue());
+			if ($result === false) {
+				// We can't be sure since it's maybe a namespaced xpath
 				return ParametersAcceptorSelector::selectSingle($methodReflection->getVariants())->getReturnType();
 			}
 
-			$result = $newResult;
 			$argType = TypeCombinator::remove($argType, $constantString);
 		}
 
-		if ($result === null || !$argType instanceof NeverType) {
+		if (!$argType instanceof NeverType) {
 			return ParametersAcceptorSelector::selectSingle($methodReflection->getVariants())->getReturnType();
 		}
 
-		if ($result === false) {
-			return new ConstantBooleanType(false);
-		}
-
 		return new ArrayType(new MixedType(), $scope->getType($methodCall->var));
 	}
 

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -3231,13 +3231,17 @@ public function dataBinaryOperations(): array
 				'$simpleXMLRightXpath',
 			],
 			[
-				'false',
+				'array<SimpleXMLElement>|false',
 				'$simpleXMLWrongXpath',
 			],
 			[
 				'array<SimpleXMLElement>|false',
 				'$simpleXMLUnknownXpath',
 			],
+			[
+				'array<SimpleXMLElement>|false',
+				'$namespacedXpath',
+			],
 		];
 	}
 

tests/PHPStan/Analyser/data/binary.php

@@ -177,6 +177,10 @@ public function doFoo(array $generalArray)
 		$simpleXMLWrongXpath = $simpleXML->xpath('[foo]');
 		$simpleXMLUnknownXpath = $simpleXML->xpath($stringForXpath);
 
+		$namespacedXML = new \SimpleXMLElement('<a><b><c/></b></a>');
+		$namespacedXML->registerXPathNamespace('ns', 'namespace');
+		$namespacedXpath = $namespacedXML->xpath('/ns:node');
+
 		if (rand(0, 1)) {
 			$maybeDefinedVariable = 'foo';
 		}