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use super::getrandom_impl;
#[cfg(all(target_arch = "wasm32", target_os = "unknown"))]
use wasm_bindgen_test::wasm_bindgen_test as test;
#[cfg(feature = "test-in-browser")]
wasm_bindgen_test::wasm_bindgen_test_configure!(run_in_browser);
#[test]
fn test_zero() {
// Test that APIs are happy with zero-length requests
getrandom_impl(&mut [0u8; 0]).unwrap();
}
// Return the number of bits in which s1 and s2 differ
#[cfg(not(feature = "custom"))]
fn num_diff_bits(s1: &[u8], s2: &[u8]) -> usize {
assert_eq!(s1.len(), s2.len());
s1.iter()
.zip(s2.iter())
.map(|(a, b)| (a ^ b).count_ones() as usize)
.sum()
}
// Tests the quality of calling getrandom on two large buffers
#[test]
#[cfg(not(feature = "custom"))]
fn test_diff() {
let mut v1 = [0u8; 1000];
getrandom_impl(&mut v1).unwrap();
let mut v2 = [0u8; 1000];
getrandom_impl(&mut v2).unwrap();
// Between 3.5 and 4.5 bits per byte should differ. Probability of failure:
// ~ 2^(-94) = 2 * CDF[BinomialDistribution[8000, 0.5], 3500]
let d = num_diff_bits(&v1, &v2);
assert!(d > 3500);
assert!(d < 4500);
}
// Tests the quality of calling getrandom repeatedly on small buffers
#[test]
#[cfg(not(feature = "custom"))]
fn test_small() {
// For each buffer size, get at least 256 bytes and check that between
// 3 and 5 bits per byte differ. Probability of failure:
// ~ 2^(-91) = 64 * 2 * CDF[BinomialDistribution[8*256, 0.5], 3*256]
for size in 1..=64 {
let mut num_bytes = 0;
let mut diff_bits = 0;
while num_bytes < 256 {
let mut s1 = vec![0u8; size];
getrandom_impl(&mut s1).unwrap();
let mut s2 = vec![0u8; size];
getrandom_impl(&mut s2).unwrap();
num_bytes += size;
diff_bits += num_diff_bits(&s1, &s2);
}
assert!(diff_bits > 3 * num_bytes);
assert!(diff_bits < 5 * num_bytes);
}
}
#[test]
fn test_huge() {
let mut huge = [0u8; 100_000];
getrandom_impl(&mut huge).unwrap();
}
// On WASM, the thread API always fails/panics
#[cfg(not(target_arch = "wasm32"))]
#[test]
fn test_multithreading() {
extern crate std;
use std::{sync::mpsc::channel, thread, vec};
let mut txs = vec![];
for _ in 0..20 {
let (tx, rx) = channel();
txs.push(tx);
thread::spawn(move || {
// wait until all the tasks are ready to go.
rx.recv().unwrap();
let mut v = [0u8; 1000];
for _ in 0..100 {
getrandom_impl(&mut v).unwrap();
thread::yield_now();
}
});
}
// start all the tasks
for tx in txs.iter() {
tx.send(()).unwrap();
}
}
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