Bug 1589590 [wpt PR 19784] - Add some tests for CompressionStream, a=testonly

Automatic update from web-platform-tests
Add some tests for CompressionStream (#19784)

Verify that CompressionStream works correctly when the input is split
into multiple chunks or when there are empty chunks in the input. Also
check that it throws when an input chunk is not a BufferSource. Make
sure that the output is actually smaller than the input for sufficiently
large input.
--

wpt-commits: 2b80e6d28f3c1ca734384ebded282bf07df80657
wpt-pr: 19784

testing/web-platform/tests/compression/compression-bad-chunks.any.js

@@ -0,0 +1,62 @@
+// META: global=worker
+
+'use strict';
+
+const badChunks = [
+  {
+    name: 'undefined',
+    value: undefined
+  },
+  {
+    name: 'null',
+    value: null
+  },
+  {
+    name: 'numeric',
+    value: 3.14
+  },
+  {
+    name: 'object, not BufferSource',
+    value: {}
+  },
+  {
+    name: 'array',
+    value: [65]
+  },
+  {
+    name: 'SharedArrayBuffer',
+    // Use a getter to postpone construction so that all tests don't fail where
+    // SharedArrayBuffer is not yet implemented.
+    get value() {
+      return new SharedArrayBuffer();
+    }
+  },
+  {
+    name: 'shared Uint8Array',
+    get value() {
+      return new Uint8Array(new SharedArrayBuffer())
+    }
+  },
+];
+
+for (const chunk of badChunks) {
+  promise_test(async t => {
+    const cs = new CompressionStream('gzip');
+    const reader = cs.readable.getReader();
+    const writer = cs.writable.getWriter();
+    const writePromise = writer.write(chunk.value);
+    const readPromise = reader.read();
+    await promise_rejects(t, new TypeError(), writePromise, 'write should reject');
+    await promise_rejects(t, new TypeError(), readPromise, 'read should reject');
+  }, `chunk of type ${chunk.name} should error the stream for gzip`);
+
+  promise_test(async t => {
+    const cs = new CompressionStream('deflate');
+    const reader = cs.readable.getReader();
+    const writer = cs.writable.getWriter();
+    const writePromise = writer.write(chunk.value);
+    const readPromise = reader.read();
+    await promise_rejects(t, new TypeError(), writePromise, 'write should reject');
+    await promise_rejects(t, new TypeError(), readPromise, 'read should reject');
+  }, `chunk of type ${chunk.name} should error the stream for deflate`);
+}

testing/web-platform/tests/compression/compression-including-empty-chunk.any.js

@@ -0,0 +1,57 @@
+// META: global=worker
+// META: script=pako/pako_inflate.min.js
+// META: timeout=long
+
+'use strict';
+
+// This test asserts that compressing '' doesn't affect the compressed data.
+// Example: compressing ['Hello', '', 'Hello'] results in 'HelloHello'
+
+async function compressChunkList(chunkList, format) {
+  const cs = new CompressionStream(format);
+  const writer = cs.writable.getWriter();
+  for (const chunk of chunkList) {
+    const chunkByte = new TextEncoder().encode(chunk);
+    writer.write(chunkByte);
+  }
+  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;
+}
+
+const chunkLists = [
+  ['', 'Hello', 'Hello'],
+  ['Hello', '', 'Hello'],
+  ['Hello', 'Hello', '']
+];
+const expectedValue = new TextEncoder().encode('HelloHello');
+
+for (const chunkList of chunkLists) {
+  promise_test(async t => {
+    const compressedData = await compressChunkList(chunkList, 'deflate');
+    // decompress with pako, and check that we got the same result as our original string
+    assert_array_equals(expectedValue, pako.inflate(compressedData), 'value should match');
+  }, `the result of compressing [${chunkList}] with deflate should be 'HelloHello'`);
+
+  promise_test(async t => {
+    const compressedData = await compressChunkList(chunkList, 'gzip');
+    // decompress with pako, and check that we got the same result as our original string
+    assert_array_equals(expectedValue, pako.inflate(compressedData), 'value should match');
+  }, `the result of compressing [${chunkList}] with gzip should be 'HelloHello'`);
+}

testing/web-platform/tests/compression/compression-multiple-chunks.any.js

@@ -0,0 +1,60 @@
+// META: global=worker
+// META: script=pako/pako_inflate.min.js
+// META: timeout=long
+
+'use strict';
+
+// This test asserts that compressing multiple chunks should work.
+
+// Example: ('Hello', 3) => TextEncoder().encode('HelloHelloHello')
+function makeExpectedChunk(input, numberOfChunks) {
+  const expectedChunk = input.repeat(numberOfChunks);
+  return new TextEncoder().encode(expectedChunk);
+}
+
+// Example: ('Hello', 3, 'deflate') => compress ['Hello', 'Hello', Hello']
+async function compressMultipleChunks(input, numberOfChunks, format) {
+  const cs = new CompressionStream(format);
+  const writer = cs.writable.getWriter();
+  const chunk = new TextEncoder().encode(input);
+  for (let i = 0; i < numberOfChunks; ++i) {
+    writer.write(chunk);
+  }
+  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;
+}
+
+const hello = 'Hello';
+
+for (let numberOfChunks = 2; numberOfChunks <= 16; ++numberOfChunks) {
+  promise_test(async t => {
+    const compressedData = await compressMultipleChunks(hello, numberOfChunks, 'deflate');
+    const expectedValue = makeExpectedChunk(hello, numberOfChunks);
+    // decompress with pako, and check that we got the same result as our original string
+    assert_array_equals(expectedValue, pako.inflate(compressedData), 'value should match');
+  }, `compressing ${numberOfChunks} chunks with deflate should work`);
+
+  promise_test(async t => {
+    const compressedData = await compressMultipleChunks(hello, numberOfChunks, 'gzip');
+    const expectedValue = makeExpectedChunk(hello, numberOfChunks);
+    // decompress with pako, and check that we got the same result as our original string
+    assert_array_equals(expectedValue, pako.inflate(compressedData), 'value should match');
+  }, `compressing ${numberOfChunks} chunks with gzip should work`);
+}

testing/web-platform/tests/compression/compression-output-length.any.js

@@ -0,0 +1,54 @@
+// META: global=worker
+
+'use strict';
+
+// This test asserts that compressed data length is shorter than the original
+// data length. If the input is extremely small, the compressed data may be
+// larger than the original data.
+
+const LARGE_FILE = '/media/test-av-384k-44100Hz-1ch-320x240-30fps-10kfr.webm';
+
+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;
+}
+
+promise_test(async () => {
+  const response = await fetch(LARGE_FILE);
+  const buffer = await response.arrayBuffer();
+  const bufferView = new Uint8Array(buffer);
+  const originalLength = bufferView.length;
+  const compressedData = await compressArrayBuffer(bufferView, 'deflate');
+  const compressedLength = compressedData.length;
+  assert_less_than(compressedLength, originalLength, 'output should be smaller');
+}, 'the length of deflated data should be shorter than that of the original data');
+
+promise_test(async () => {
+  const response = await fetch(LARGE_FILE);
+  const buffer = await response.arrayBuffer();
+  const bufferView = new Uint8Array(buffer);
+  const originalLength = bufferView.length;
+  const compressedData = await compressArrayBuffer(bufferView, 'gzip');
+  const compressedLength = compressedData.length;
+  assert_less_than(compressedLength, originalLength, 'output should be smaller');
+}, 'the length of gzipped data should be shorter than that of the original data');