1use canic::cdk::types::{Account, Principal};
2
3pub mod pic;
4
5pub struct Fake;
10
11impl Fake {
12 #[must_use]
13 pub fn account(seed: u32) -> Account {
14 let mut sub = [0u8; 32];
15 let bytes = seed.to_be_bytes();
16 sub[..4].copy_from_slice(&bytes);
17
18 Account {
19 owner: Self::principal(seed),
20 subaccount: Some(sub),
21 }
22 }
23
24 #[must_use]
25 pub fn principal(seed: u32) -> Principal {
26 let mut buf = [0u8; 29];
27 buf[..4].copy_from_slice(&seed.to_be_bytes());
28
29 Principal::from_slice(&buf)
30 }
31}
32
33#[cfg(test)]
38mod tests {
39 use super::*;
40
41 #[test]
42 fn fake_account_is_deterministic_and_unique() {
43 let a1 = Fake::account(42);
44 let a2 = Fake::account(42);
45 let b = Fake::account(99);
46
47 assert_eq!(a1, a2, "Fake::account should be deterministic");
49
50 assert_ne!(a1, b, "Fake::account should vary by seed");
52 }
53
54 #[test]
55 fn fake_principal_is_deterministic_and_unique() {
56 let p1 = Fake::principal(7);
57 let p2 = Fake::principal(7);
58 let q = Fake::principal(8);
59
60 assert_eq!(p1, p2, "Fake::principal should be deterministic");
61 assert_ne!(p1, q, "Fake::principal should differ for different seeds");
62
63 let bytes = p1.as_slice();
64 assert_eq!(bytes.len(), 29, "Principal must be 29 bytes");
65 }
66}