piping issue

[jimmywarting]

I have included the web streams polyfill into my project and I'm trying to pipe a readableStream to a writableStream

This is very simplified but it seems to work fine (it dose what i want it to do).
The writable stream gets all chunks it closes when the readableStream closes...

var rs = new ReadableStream({
    start(c) {
        c.enqueue(5);
        c.close();
    }
})

var ws = new WritableStream({})

rs.pipeTo(ws)

But as soon as i .close() the ReadableStream it logs 3 TypeError

Uncaught (in promise) TypeError: Reader was released and can no longer be used to monitor the stream's closedness(…)
Uncaught (in promise) TypeError: Writer was released and can no longer be used to monitor the stream's closedness(…)
Uncaught (in promise) TypeError: Writer was released and can no longer be used to monitor the stream's closedness(…)

I'm doing something wrong?

[domenic]

It's possible this is a bug in our implementation of pipeTo. We still are working to get that specced and implemented better. I'll try to fix that as we work on it.

[jimmywarting]

Cool, thanks for letting me know. Hopefully I didn't do anything wrong and i just helped you find a bug :)

I know it's undergoing some changes ATM. But i like to prepare for what is coming 😉

[isonmad]

I don't think this is pipeTo-specific. It's what always happens when the .closed promise is rejected, which happens when you do reader.releaseLock(). It happens twice for writer because it sets both .closed and .ready to rejected.

new ReadableStream().getReader().releaseLock();
new WritableStream().getWriter().releaseLock();

The promises would have to be lazily rejected in get closed() to avoid the warnings, wouldn't they?

[domenic]

Let's roll this into #547.