Neos\Flow\Property\TypeConverter\ObjectConverter::getTypeOfChildProperty PHP Method

    public function getTypeOfChildProperty($targetType, $propertyName, PropertyMappingConfigurationInterface $configuration)
    {
        $configuredTargetType = $configuration->getConfigurationFor($propertyName)->getConfigurationValue(ObjectConverter::class, self::CONFIGURATION_TARGET_TYPE);
        if ($configuredTargetType !== null) {
            return $configuredTargetType;
        }
        $methodParameters = $this->reflectionService->getMethodParameters($targetType, '__construct');
        if (isset($methodParameters[$propertyName]) && isset($methodParameters[$propertyName]['type'])) {
            return $methodParameters[$propertyName]['type'];
        } elseif ($this->reflectionService->hasMethod($targetType, ObjectAccess::buildSetterMethodName($propertyName))) {
            $methodParameters = $this->reflectionService->getMethodParameters($targetType, ObjectAccess::buildSetterMethodName($propertyName));
            $methodParameter = current($methodParameters);
            if (!isset($methodParameter['type'])) {
                throw new InvalidTargetException('Setter for property "' . $propertyName . '" had no type hint or documentation in target object of type "' . $targetType . '".', 1303379158);
            } else {
                return $methodParameter['type'];
            }
        } else {
            $targetPropertyNames = $this->reflectionService->getClassPropertyNames($targetType);
            if (in_array($propertyName, $targetPropertyNames)) {
                $varTagValues = $this->reflectionService->getPropertyTagValues($targetType, $propertyName, 'var');
                if (count($varTagValues) > 0) {
                    // This ensures that FQCNs are returned without leading backslashes. Otherwise, something like @var \DateTime
                    // would not find a property mapper. It is needed because the ObjectConverter doesn't use class schemata,
                    // but reads the annotations directly.
                    $declaredType = strtok(trim(current($varTagValues), " \n\t"), " \n\t");
                    try {
                        $parsedType = TypeHandling::parseType($declaredType);
                    } catch (InvalidTypeException $exception) {
                        throw new \InvalidArgumentException(sprintf($exception->getMessage(), 'class "' . $targetType . '" for property "' . $propertyName . '"'), 1467699674);
                    }
                    return $parsedType['type'] . ($parsedType['elementType'] !== null ? '<' . $parsedType['elementType'] . '>' : '');
                } else {
                    throw new InvalidTargetException(sprintf('Public property "%s" had no proper type annotation (i.e. "@var") in target object of type "%s".', $propertyName, $targetType), 1406821818);
                }
            }
        }
        throw new InvalidTargetException(sprintf('Property "%s" has neither a setter or constructor argument, nor is public, in target object of type "%s".', $propertyName, $targetType), 1303379126);
    }

 /**
  * @test
  */
 public function getTypeOfChildPropertyShouldRemoveLeadingBackslashesForAnnotationParameters()
 {
     $this->mockReflectionService->expects($this->any())->method('getMethodParameters')->with('TheTargetType', '__construct')->will($this->returnValue([]));
     $this->mockReflectionService->expects($this->any())->method('hasMethod')->with('TheTargetType', 'setThePropertyName')->will($this->returnValue(false));
     $this->mockReflectionService->expects($this->any())->method('getClassPropertyNames')->with('TheTargetType')->will($this->returnValue(['thePropertyName']));
     $this->mockReflectionService->expects($this->any())->method('getPropertyTagValues')->with('TheTargetType', 'thePropertyName')->will($this->returnValue(['\\TheTypeOfSubObject']));
     $configuration = new PropertyMappingConfiguration();
     $configuration->setTypeConverterOptions(ObjectConverter::class, []);
     $this->assertEquals('TheTypeOfSubObject', $this->converter->getTypeOfChildProperty('TheTargetType', 'thePropertyName', $configuration));
 }