Can you test if #58639 would fix it for you?

@xabbuh yes, with that code it works

Unfortunately the solution is not that simple as this change now breaks other things.

Maybe you shouldn't decorate this way: the TagAwareAdapter in between is of no use with PSR-16.

I think there might be conflicting expectations here: IIRC, the current code is meant to allow tags to work through PSR-16/16 (aka being able to use a PSR-6/16 storage that'd work with tags).

Not every decoration order is supposed to work.

why the get function is not taking into account the metadata but getMultiple is?

That's good point, we might be a bit light on this topic, test cases are missing for sure, that'd document the use cases and prevent regressions.

When I was working on the patch I was in fact wondering if our way of returning metadata (in some cases) in getMultiple() is actually conform with PSR16. On the other hand as the failing tests in #58639 show without them writing an adapter for the other direction becomes harder (impossible?).

In my opinion, the MR is ok and the problem is in Psr16Adapter

The failing tests is due that adapter. I think the adapter should wrap the value into an object to support metadata. And always unwrap it again. So the wrap is done in that adapter and not in PSR16Cache.

Hey, thanks for your report!
There has not been a lot of activity here for a while. Is this bug still relevant? Have you managed to find a workaround?

Hi, in my opinion is still relevant.

The How to reproduce section is still failing (using symfony 7.2.5)

My workaround was map the values:

    public function getMultiple(iterable $keys, mixed $default = null): iterable
    {
        $data = $this->cache->getMultiple($keys, $default);

        return self::fixGetMultiple($data);
    }

    public static function fixGetMultiple(iterable $data): iterable
    {
        // https://github.com/symfony/symfony/issues/58632
        $wrapperClass = "\xA9";

        if (false === class_exists($wrapperClass)) {
            return $data;
        }

        return map(
            static function (mixed $value) use ($wrapperClass) {
                if ($value instanceof $wrapperClass) {
                    return $value->value;
                }

                return $value;
            },
            $data,
        );
    }