createContainerExtension example

    }

    /** * Returns the bundle's container extension. * * @throws \LogicException */
    public function getContainerExtension(): ?ExtensionInterface
    {
        if (null === $this->extension) {
            $extension = $this->createContainerExtension();

            if (null !== $extension) {
                if (!$extension instanceof ExtensionInterface) {
                    throw new \LogicException(sprintf('Extension "%s" must implement Symfony\Component\DependencyInjection\Extension\ExtensionInterface.', get_debug_type($extension)));
                }

                // check naming convention                 $basename = preg_replace('/Bundle$/', '', $this->getName());
                $expectedAlias = Container::underscore($basename);

                if ($expectedAlias != $extension->getAlias()) {
                    

    }

    /** * Returns the bundle's container extension. * * @throws \LogicException */
    public function getContainerExtension(): ?ExtensionInterface
    {
        if (!isset($this->extension)) {
            $extension = $this->createContainerExtension();

            if (null !== $extension) {
                if (!$extension instanceof ExtensionInterface) {
                    throw new \LogicException(sprintf('Extension "%s" must implement Symfony\Component\DependencyInjection\Extension\ExtensionInterface.', get_debug_type($extension)));
                }

                // check naming convention                 $basename = preg_replace('/Bundle$/', '', $this->getName());
                $expectedAlias = Container::underscore($basename);

                if ($expectedAlias != $extension->getAlias()) {