std/streams/limited_bytes_transform_stream_test.ts

// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.

import { assertEquals, assertRejects } from "../assert/mod.ts";
import { LimitedBytesTransformStream } from "./limited_bytes_transform_stream.ts";

Deno.test("LimitedBytesTransformStream", async function () {
  const r = ReadableStream.from([
    new Uint8Array([1, 2, 3]),
    new Uint8Array([4, 5, 6]),
    new Uint8Array([7, 8, 9]),
    new Uint8Array([10, 11, 12]),
    new Uint8Array([13, 14, 15]),
    new Uint8Array([16, 17, 18]),
  ]).pipeThrough(new LimitedBytesTransformStream(7));

  const chunks = await Array.fromAsync(r);
  assertEquals(chunks.length, 2);
});

Deno.test("LimitedBytesTransformStream handles error", async function () {
  const r = ReadableStream.from([
    new Uint8Array([1, 2, 3]),
    new Uint8Array([4, 5, 6]),
    new Uint8Array([7, 8, 9]),
    new Uint8Array([10, 11, 12]),
    new Uint8Array([13, 14, 15]),
    new Uint8Array([16, 17, 18]),
  ]).pipeThrough(new LimitedBytesTransformStream(7, { error: true }));

  await assertRejects(async () => await Array.fromAsync(r), RangeError);
});