Improve annotation reader to traverse class hierarchy (#94)

* Improve annotation reader consider traverse class hierarchy

* Catch reflection exception

Author: marcospassos

phpstan.neon.dist

@@ -21,6 +21,9 @@ parameters:
 			- PHPUnit\Framework\Exception
 			- Nette\DI\MissingServiceException
 		methodThrowTypeDeclarations:
+			ReflectionMethod:
+				getPrototype:
+					- ReflectionException
 			PHPStan\Broker\Broker:
 				getClass:
 					- PHPStan\Broker\ClassNotFoundException

src/ThrowsAnnotationReader.php

@@ -130,9 +130,19 @@ private function getDocblock($reflection): ?string
 	{
 		if ($reflection instanceof MethodReflection) {
 			$declaringClass = $reflection->getDeclaringClass();
-			$nativeClassReflection = $declaringClass->getNativeReflection();
-			$nativeMethodReflection = $nativeClassReflection->getMethod($reflection->getName());
-			$docBlock = $nativeMethodReflection->getDocComment();
+			$classReflection = $declaringClass->getNativeReflection();
+			$methodReflection = $classReflection->getMethod($reflection->getName());
+			$docBlock = $methodReflection->getDocComment();
+
+			while ($docBlock === false) {
+				try {
+					$methodReflection = $methodReflection->getPrototype();
+				} catch (ReflectionException $exception) {
+					return null;
+				}
+
+				$docBlock = $methodReflection->getDocComment();
+			}
 
 			return $docBlock !== false ? $docBlock : null;
 		}

tests/src/Rules/data/unused-descriptive-throws.php

@@ -57,9 +57,22 @@ function descriptiveAnnotationAlias(): void
 	throw new LogicException();
 }
 
-class UnusedThrows
+interface Foo {
+
+	/**
+	 * @throws LogicException Description.
+	 */
+	public function uncheckedException(): void;
+}
+
+class UnusedThrows implements Foo
 {
 
+	public function uncheckedException() : void
+	{
+		throw new LogicException();
+	}
+
 	/**
 	 * @throws RuntimeException
 	 * @throws RuntimeException Description.