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
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
import { assert, assertEquals } from "../assert/mod.ts";import { copy } from "../io/copy.ts";import { readerFromStreamReader } from "./reader_from_stream_reader.ts";import { Buffer } from "../io/buffer.ts";
function repeat(c: string, bytes: number): Uint8Array {  assertEquals(c.length, 1);  const ui8 = new Uint8Array(bytes);  ui8.fill(c.charCodeAt(0));  return ui8;}
Deno.test("readerFromStreamReader()", async function () {  const chunks: string[] = ["hello", "deno", "land"];  const expected = chunks.slice();  const readChunks: Uint8Array[] = [];  const readableStream = ReadableStream.from(chunks)    .pipeThrough(new TextEncoderStream());
  const decoder = new TextDecoder();  const reader = readerFromStreamReader(readableStream.getReader());
  let i = 0;
  while (true) {    const b = new Uint8Array(1024);    const n = await reader.read(b);
    if (n === null) break;
    readChunks.push(b.subarray(0, n));    assert(i < expected.length);
    i++;  }
  assertEquals(    expected,    readChunks.map((chunk) => decoder.decode(chunk)),  );});
Deno.test("readerFromStreamReader() handles big chunks", async function () {  const bufSize = 1024;  const chunkSize = 3 * bufSize;  const writer = new Buffer();
  // A readable stream can enqueue chunks bigger than Copy bufSize  // Reader returned by toReader should enqueue exceeding bytes  const chunks: string[] = [    "a".repeat(chunkSize),    "b".repeat(chunkSize),    "c".repeat(chunkSize),  ];  const expected = chunks.slice();  const readableStream = ReadableStream.from(chunks)    .pipeThrough(new TextEncoderStream());
  const reader = readerFromStreamReader(readableStream.getReader());  const n = await copy(reader, writer, { bufSize });
  const expectedWritten = chunkSize * expected.length;  assertEquals(n, chunkSize * expected.length);  assertEquals(writer.length, expectedWritten);});
Deno.test("readerFromStreamReader() handles irregular chunks", async function () {  const bufSize = 1024;  const chunkSize = 3 * bufSize;  const writer = new Buffer();
  // A readable stream can enqueue chunks bigger than Copy bufSize  // Reader returned by toReader should enqueue exceeding bytes  const chunks: Uint8Array[] = [    repeat("a", chunkSize),    repeat("b", chunkSize + 253),    repeat("c", chunkSize + 8),  ];  const expected = new Uint8Array(    chunks      .slice()      .map((chunk) => [...chunk])      .flat(),  );  const readableStream = ReadableStream.from(chunks);
  const reader = readerFromStreamReader(readableStream.getReader());
  const n = await copy(reader, writer, { bufSize });  assertEquals(n, expected.length);  assertEquals(expected, writer.bytes());});