Close at pull - Web Stream

run.mjs

/*
 * ```
 * $ node ./run.mjs && deno run ./run.mjs && echo ok
 * ok
 * ```
 */

if (typeof process !== "undefined") {
    const { ReadableStream, WritableStream } = await import("stream/web");
    Object.assign(globalThis, {
        ReadableStream,
        WritableStream,
    });
}

const stream = new ReadableStream({
    pull(controller) {
        const request = controller.byobRequest;
        if (!request) {
            throw new Error();
        }
        controller.close();
        request.respond(0);
    },
    type: "bytes",
});

const reader = stream.getReader({ mode: "byob" });
const buf = new Uint8Array(16);
const { done, value } = await reader.read(buf);
if (!done || value.byteLength !== 0) {
    throw new Error();
}