Add SimpleXMLElementExtension (#143)

Author: VincentLanglet

extension.neon

@@ -62,6 +62,11 @@ services:
 		tags:
 			- exceptionRules.dynamicConstructorThrowTypeExtension
 
+	-
+		class: Pepakriz\PHPStanExceptionRules\Extension\SimpleXMLElementExtension
+		tags:
+			- exceptionRules.dynamicConstructorThrowTypeExtension
+
 	-
 		class: Pepakriz\PHPStanExceptionRules\Extension\SplFileObjectExtension
 		tags:

src/Extension/SimpleXMLElementExtension.php

@@ -0,0 +1,64 @@
+<?php declare(strict_types = 1);
+
+namespace Pepakriz\PHPStanExceptionRules\Extension;
+
+use Exception;
+use Pepakriz\PHPStanExceptionRules\DynamicConstructorThrowTypeExtension;
+use Pepakriz\PHPStanExceptionRules\UnsupportedClassException;
+use PhpParser\Node\Arg;
+use PhpParser\Node\Expr\New_;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\MethodReflection;
+use PHPStan\Type\NeverType;
+use PHPStan\Type\ObjectType;
+use PHPStan\Type\Type;
+use PHPStan\Type\TypeCombinator;
+use PHPStan\Type\TypeUtils;
+use PHPStan\Type\VoidType;
+use SimpleXMLElement;
+use function is_a;
+
+class SimpleXMLElementExtension implements DynamicConstructorThrowTypeExtension
+{
+
+	/**
+	 * @throws UnsupportedClassException
+	 */
+	public function getThrowTypeFromConstructor(MethodReflection $methodReflection, New_ $newNode, Scope $scope): Type
+	{
+		if (is_a($methodReflection->getDeclaringClass()->getName(), SimpleXMLElement::class, true)) {
+			return $this->resolveThrowType($newNode->args, $scope);
+		}
+
+		throw new UnsupportedClassException();
+	}
+
+	/**
+	 * @param Arg[] $args
+	 */
+	private function resolveThrowType(array $args, Scope $scope): Type
+	{
+		$exceptionType = new ObjectType(Exception::class);
+		if (!isset($args[0])) {
+			return $exceptionType;
+		}
+
+		$valueType = $scope->getType($args[0]->value);
+		foreach (TypeUtils::getConstantStrings($valueType) as $constantString) {
+			try {
+				new SimpleXMLElement($constantString->getValue());
+			} catch (Exception $e) {
+				return $exceptionType;
+			}
+
+			$valueType = TypeCombinator::remove($valueType, $constantString);
+		}
+
+		if (!$valueType instanceof NeverType) {
+			return $exceptionType;
+		}
+
+		return new VoidType();
+	}
+
+}

tests/src/Rules/PhpInternalsTest.php

@@ -11,6 +11,7 @@
 use Pepakriz\PHPStanExceptionRules\Extension\IntdivExtension;
 use Pepakriz\PHPStanExceptionRules\Extension\JsonEncodeDecodeExtension;
 use Pepakriz\PHPStanExceptionRules\Extension\ReflectionExtension;
+use Pepakriz\PHPStanExceptionRules\Extension\SimpleXMLElementExtension;
 use Pepakriz\PHPStanExceptionRules\Extension\SplFileObjectExtension;
 use Pepakriz\PHPStanExceptionRules\RuleTestCase;
 use PHPStan\Rules\Rule;
@@ -31,6 +32,7 @@ protected function getRule(): Rule
 		$jsonEncodeDecodeExtension = new JsonEncodeDecodeExtension();
 		$intdivExtension = new IntdivExtension();
 		$domDocumentExtension = new DOMDocumentExtension();
+		$simpleXMLElementEtension = new SimpleXMLElementExtension();
 
 		return new ThrowsPhpDocRule(
 			new CheckedExceptionService(
@@ -48,6 +50,7 @@ protected function getRule(): Rule
 					$dateIntervalExtension,
 					$dateTimeExtension,
 					$splFileObjectExtension,
+					$simpleXMLElementEtension,
 				],
 				[
 					$jsonEncodeDecodeExtension,

tests/src/Rules/data/throws-php-internal-functions.php

@@ -12,6 +12,7 @@
 use ReflectionObject;
 use ReflectionProperty;
 use ReflectionZendExtension;
+use SimpleXMLElement;
 use SplFileObject;
 use stdClass;
 use Throwable;
@@ -121,6 +122,13 @@ public function testSplFileObject(): void
 		new SplFileObject(); // error: Missing @throws LogicException annotation; Missing @throws RuntimeException annotation
 	}
 
+	public function testSimpleXMLElement(): void
+	{
+		new SimpleXMLElement(); // error: Missing @throws Exception annotation
+		new SimpleXMLElement('foo'); // error: Missing @throws Exception annotation
+		new SimpleXMLElement('<foo />');
+	}
+
 	public function testIntdiv(): void
 	{
 		/** @var int $integer */