compression-stream.any.js

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// META: global=window,worker,shadowrealm

// META: script=third_party/pako/pako_inflate.min.js

// META: script=resources/decompress.js

// META: script=resources/formats.js

// META: timeout=long

'use strict';

const SMALL_FILE = "/media/foo.vtt";

const LARGE_FILE = "/media/test-av-384k-44100Hz-1ch-320x240-30fps-10kfr.webm";

let dataPromiseList = [

  ["empty data", Promise.resolve(new Uint8Array(0))],

  ["small amount data", fetch(SMALL_FILE).then(response => response.bytes())],

  ["large amount data", fetch(LARGE_FILE).then(response => response.bytes())],

];

async function compressArrayBuffer(input, format) {

  const cs = new CompressionStream(format);

  const writer = cs.writable.getWriter();

  writer.write(input);

  const closePromise = writer.close();

  const out = [];

  const reader = cs.readable.getReader();

  let totalSize = 0;

  while (true) {

    const { value, done } = await reader.read();

    if (done)

      break;

    out.push(value);

    totalSize += value.byteLength;

  await closePromise;

  const concatenated = new Uint8Array(totalSize);

  let offset = 0;

  for (const array of out) {

    concatenated.set(array, offset);

    offset += array.byteLength;

  return concatenated;

test(() => {

  assert_throws_js(TypeError, () => {

    const transformer = new CompressionStream("nonvalid");

  }, "non supported format should throw");

}, "CompressionStream constructor should throw on invalid format");

for (const format of formats) {

  for (const [label, dataPromise] of dataPromiseList) {

    promise_test(async () => {

      const bufferView = await dataPromise;

      const compressedData = await compressArrayBuffer(bufferView, format);

      const decompressedData = await decompressDataOrPako(compressedData, format);

      // check that we got the same result as our original string

      assert_array_equals(decompressedData, bufferView, 'value should match');

    }, `${format} ${label} should be reinflated back to its origin`);