blob: 465feaa47d4e9af02fb86b9a36b698aa9c465fbe (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
// META: global=window,worker,shadowrealm
// META: script=resources/concatenate-stream.js
'use strict';
const kInputLength = 500000;
function createLargeRandomInput() {
const buffer = new ArrayBuffer(kInputLength);
// The getRandomValues API will only let us get 65536 bytes at a time, so call
// it multiple times.
const kChunkSize = 65536;
for (let offset = 0; offset < kInputLength; offset += kChunkSize) {
const length =
offset + kChunkSize > kInputLength ? kInputLength - offset : kChunkSize;
const view = new Uint8Array(buffer, offset, length);
crypto.getRandomValues(view);
}
return new Uint8Array(buffer);
}
function decompress(view) {
const ds = new DecompressionStream('deflate');
const writer = ds.writable.getWriter();
writer.write(view);
writer.close();
return concatenateStream(ds.readable);
}
promise_test(async () => {
const input = createLargeRandomInput();
const inputCopy = input.slice(0, input.byteLength);
const cs = new CompressionStream('deflate');
const writer = cs.writable.getWriter();
writer.write(input);
writer.close();
// Object.prototype.then will be looked up synchronously when the promise
// returned by read() is resolved.
Object.defineProperty(Object.prototype, 'then', {
get() {
// Cause input to become detached and unreferenced.
try {
postMessage(undefined, 'nowhere', [input.buffer]);
} catch (e) {
// It's already detached.
}
}
});
const output = await concatenateStream(cs.readable);
// Perform the comparison as strings since this is reasonably fast even when
// JITted JavaScript is running under an emulator.
assert_equals(
inputCopy.toString(), (await decompress(output)).toString(),
'decompressing the output should return the input');
}, 'data should be correctly compressed even if input is detached partway');
|
