src/Reflection/Adapter/ReflectionClass.php
public function implementsInterface($interface)
    {
        $realInterfaceNames = $this->betterReflectionClass->getInterfaceNames();

        $interfaceNames = array_combine(array_map(static function (string $interfaceName) : string {
            return strtolower($interfaceName);
        }, $realInterfaceNames), $realInterfaceNames);

        $realInterfaceName = $interfaceNames[strtolower($interface)] ?? $interface;

        return $this->betterReflectionClass->implementsInterface($realInterfaceName);
    }
public function implementsInterface($interface)
    {
        $realInterfaceNames = $this->betterReflectionClass->getInterfaceNames();

        $interfaceNames = array_combine(array_map(static function (string $interfaceName) : string {
            return strtolower($interfaceName);
        }, $realInterfaceNames), $realInterfaceNames);

        $realInterfaceName = $interfaceNames[strtolower($interface)] ?? $interface;

        return $this->betterReflectionClass->implementsInterface($realInterfaceName);
    }
{@inheritDoc}