(previously
https://news.ycombinator.com/item?id=48060054 )
Didn't actually want to write a test myself.. but I miss Claudia confirmed it. Pretty concerning.
Synchronous / serial calls:
import rng from './rng';
const a = rng();
console.log('a after first call: ', Array.from(a));
const b = rng();
console.log('a after second call:', Array.from(a));
console.log('b after second call:', Array.from(b));
console.log('a === b (same reference)? ', a === b);
console.log('a equals b (same contents)? ', a.every((v, i) => v === b[i]));
output:
a after first call: [
101, 193, 125, 19, 142,
136, 181, 140, 209, 224,
176, 153, 179, 248, 246,
166
]
a after second call: [
4, 29, 48, 215, 162, 60,
64, 23, 78, 137, 2, 186,
230, 249, 70, 224
]
b after second call: [
4, 29, 48, 215, 162, 60,
64, 23, 78, 137, 2, 186,
230, 249, 70, 224
]
a === b (same reference)? true
a equals b (same contents)? true
and aynchronous calls:
import rng from './rng';
async function getId() {
const bytes = rng();
await new Promise(r => setTimeout(r, 0)); // yield to the event loop
return Array.from(bytes);
}
const [id1, id2] = await Promise.all([getId(), getId()]);
console.log('id1:', id1);
console.log('id2:', id2);
console.log('identical?', id1.every((v, i) => v === id2[i]));
output:
id1 captured: [
61, 116, 151, 35, 153,
75, 105, 15, 59, 235,
162, 215, 224, 115, 31,
122
]
id2 captured: [
13, 3, 84, 28, 22, 176,
160, 70, 67, 246, 1, 37,
38, 61, 171, 23
]
id1 after await: [
13, 3, 84, 28, 22, 176,
160, 70, 67, 246, 1, 37,
38, 61, 171, 23
]
id2 after await: [
13, 3, 84, 28, 22, 176,
160, 70, 67, 246, 1, 37,
38, 61, 171, 23
]
---
final id1: [
13, 3, 84, 28, 22, 176,
160, 70, 67, 246, 1, 37,
38, 61, 171, 23
]
final id2: [
13, 3, 84, 28, 22, 176,
160, 70, 67, 246, 1, 37,
38, 61, 171, 23
]
identical? true