support `DecompressionStream` when available about fflate HOT 7 CLOSED

import { assert } from "https://deno.land/[email protected]/assert/mod.ts";
import * as fflate from "npm:fflate";
import * as pako from "npm:pako";

async function decode_stream(stream: ReadableStream) {
  const reader = stream
    .pipeThrough(new DecompressionStream("gzip"))
    .getReader();
  let bytes: Uint8Array;
  {
    const result = await reader.read();
    assert(!result.done, "ReadableStream must have data");
    bytes = result.value;
  }
  {
    const result = await reader.read();
    assert(result.done, "ReadableStream must have no more data");
  }
  return bytes;
}

const base = new URL(
  "https://raw.githubusercontent.com/zarr-developers/zarr_implementations/5dc998ac72/examples/zarr.zr/gzip/.zarray",
);

const BYTES = await fetch(new URL("0.0.0", base))
  .then((r) => r.arrayBuffer())
  .then((b) => new Uint8Array(b));

const REFERENCE = fflate.gunzipSync(BYTES);

Deno.bench("decode_stream", async () => {
  const stream = new ReadableStream({
    start(controller) {
      controller.enqueue(BYTES);
      controller.close();
    },
  });
  const result = await decode_stream(stream);
  assert(result.length === REFERENCE.length);
});

Deno.bench("fflate.gunzip", () => {
  const result = fflate.gunzipSync(BYTES);
  assert(result.length === REFERENCE.length);
});

Deno.bench("pako.inflate", () => {
  const result = pako.inflate(BYTES);
  assert(result.length === REFERENCE.length);
});