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
// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.import { createAbortError, exponentialBackoffWithJitter } from "./_util.ts";import { assertEquals, assertInstanceOf } from "../assert/mod.ts";
// test util to ensure deterministic results during testing of backoff function by polyfilling Math.randomfunction prngMulberry32(seed: number) {  return function () {    let t = (seed += 0x6d2b79f5);    t = Math.imul(t ^ (t >>> 15), t | 1);    t ^= t + Math.imul(t ^ (t >>> 7), t | 61);    return ((t ^ (t >>> 14)) >>> 0);  };}
// random seed generated with crypto.getRandomValues(new Uint32Array(1))[0]const INITIAL_SEED = 3460544849;
const expectedTimings: readonly (readonly number[] & { length: 10 })[] & {  length: 10;} = [  [31, 117, 344, 9, 1469, 1060, 920, 5094, 19564, 33292],  [46, 184, 377, 419, 1455, 483, 3205, 8426, 22451, 29810],  [68, 17, 66, 645, 1209, 246, 3510, 4598, 398, 12813],  [46, 111, 374, 626, 859, 1955, 5379, 609, 5766, 33641],  [26, 129, 287, 757, 1104, 4, 2557, 4940, 16657, 6888],  [80, 71, 348, 245, 743, 128, 2445, 5722, 19960, 49861],  [25, 46, 341, 498, 602, 2349, 1366, 4399, 1680, 9275],  [14, 174, 189, 309, 1461, 937, 1898, 2087, 9624, 18872],  [65, 190, 382, 351, 826, 2502, 5657, 3967, 1063, 43754],  [89, 78, 222, 668, 1027, 1397, 1293, 8295, 14077, 33602],] as const;
Deno.test("exponentialBackoffWithJitter()", () => {  let nextSeed = INITIAL_SEED;
  for (const row of expectedTimings) {    const randUint32 = prngMulberry32(nextSeed);    nextSeed = prngMulberry32(nextSeed)();    Math.random = () => randUint32() / 0x100000000;
    const results: number[] = [];    const base = 100;    const cap = Infinity;
    for (let i = 0; i < 10; ++i) {      const result = exponentialBackoffWithJitter(cap, base, i, 2, 1);      results.push(Math.round(result));    }
    assertEquals(results as typeof row, row);  }});
Deno.test("createAbortError()", () => {  const error = createAbortError();  assertInstanceOf(error, DOMException);  assertEquals(error.name, "AbortError");  assertEquals(error.message, "Aborted");});
Deno.test("createAbortError() handles aborted signal with reason", () => {  const c = new AbortController();  c.abort("Expected Reason");  const error = createAbortError(c.signal.reason);  assertInstanceOf(error, DOMException);  assertEquals(error.name, "AbortError");  assertEquals(error.message, "Aborted: Expected Reason");});
Deno.test("createAbortError() handles aborted signal without reason", () => {  const c = new AbortController();  c.abort();  const error = createAbortError(c.signal.reason);  assertInstanceOf(error, DOMException);  assertEquals(error.name, "AbortError");  assertEquals(    error.message,    "Aborted: AbortError: The signal has been aborted",  );});