src/ResourcePool/Standard.php
public function save(ResourceInterface $resource): bool
    {
        if (!$this->savesResource($resource->getType())) {
            return false;
        }

        $key = $this->generateKey(
            $resource->getType(),
            $resource->getId(),
            ['locale' => $this->getResourceLocale($resource)]
        );

        $exists = isset($this->resources[$key]);
        $this->resources[$key] = $resource;

        return !$exists;
    }
public function save(ResourceInterface $resource): bool
    {
        if (!$this->savesResource($resource->getType())) {
            return false;
        }

        $key = $this->generateKey(
            $resource->getType(),
            $resource->getId(),
            ['locale' => $this->getResourceLocale($resource)]
        );

        $exists = isset($this->resources[$key]);
        $this->resources[$key] = $resource;

        return !$exists;
    }
{@inheritdoc}