1  // Copyright (c) 2025-2026 ACDC Network
 2  // This file is part of the alphavm library.
 3  //
 4  // Alpha Chain | Delta Chain Protocol
 5  // International Monetary Graphite.
 6  //
 7  // Derived from Aleo (https://aleo.org) and ProvableHQ (https://provable.com).
 8  // They built world-class ZK infrastructure. We installed the EASY button.
 9  // Their cryptography: elegant. Our modifications: bureaucracy-compatible.
10  // Original brilliance: theirs. Robert's Rules: ours. Bugs: definitely ours.
11  //
12  // Original Aleo/ProvableHQ code subject to Apache 2.0 https://www.apache.org/licenses/LICENSE-2.0
13  // All modifications and new work: CC0 1.0 Universal Public Domain Dedication.
14  // No rights reserved. No permission required. No warranty. No refunds.
15  //
16  // https://creativecommons.org/publicdomain/zero/1.0/
17  // SPDX-License-Identifier: CC0-1.0
18  
19  use super::*;
20  
21  impl<E: Environment> Distribution<StringType<E>> for Standard {
22      #[inline]
23      fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> StringType<E> {
24          // Sample a random number up to 1/4th of the maximum bytes.
25          let num_bytes = rng.gen_range(1..(E::MAX_STRING_BYTES / 4) as usize);
26          // Sample a random string.
27          StringType::new(&rng.sample_iter(&Alphanumeric).take(num_bytes).map(char::from).collect::<String>())
28      }
29  }
30  
31  #[cfg(test)]
32  mod tests {
33      use super::*;
34      use alphavm_console_network_environment::Console;
35  
36      use std::collections::HashMap;
37  
38      type CurrentEnvironment = Console;
39  
40      const ITERATIONS: usize = 100;
41  
42      #[test]
43      fn test_random() {
44          // Initialize a map[string]=>occurrences to store all seen random elements.
45          let mut map = HashMap::with_capacity(ITERATIONS);
46  
47          let mut rng = TestRng::default();
48  
49          for _ in 0..ITERATIONS {
50              // Sample a random value.
51              let string: StringType<CurrentEnvironment> = Uniform::rand(&mut rng);
52  
53              // Add the new random value to the set.
54              map.entry(string).and_modify(|count| *count += 1).or_insert(1);
55          }
56          for (string, count) in map {
57              let allowed_occurrences = 1 + ITERATIONS / (string.len() * 10);
58              assert!(count <= allowed_occurrences, "Encountered an element with a count of {count}: {string}");
59          }
60      }
61  }