snarkvm_console_types_string/
random.rs

1// Copyright 2024 Aleo Network Foundation
2// This file is part of the snarkVM library.
3
4// Licensed under the Apache License, Version 2.0 (the "License");
5// you may not use this file except in compliance with the License.
6// You may obtain a copy of the License at:
7
8// http://www.apache.org/licenses/LICENSE-2.0
9
10// Unless required by applicable law or agreed to in writing, software
11// distributed under the License is distributed on an "AS IS" BASIS,
12// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13// See the License for the specific language governing permissions and
14// limitations under the License.
15
16use super::*;
17
18impl<E: Environment> Distribution<StringType<E>> for Standard {
19    #[inline]
20    fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> StringType<E> {
21        // Sample a random number up to 1/4th of the maximum bytes.
22        let num_bytes = rng.gen_range(1..(E::MAX_STRING_BYTES / 4) as usize);
23        // Sample a random string.
24        StringType::new(&rng.sample_iter(&Alphanumeric).take(num_bytes).map(char::from).collect::<String>())
25    }
26}
27
28#[cfg(test)]
29mod tests {
30    use super::*;
31    use snarkvm_console_network_environment::Console;
32
33    use std::collections::HashMap;
34
35    type CurrentEnvironment = Console;
36
37    const ITERATIONS: usize = 100;
38
39    #[test]
40    fn test_random() {
41        // Initialize a map[string]=>occurences to store all seen random elements.
42        let mut map = HashMap::with_capacity(ITERATIONS);
43
44        let mut rng = TestRng::default();
45
46        for _ in 0..ITERATIONS {
47            // Sample a random value.
48            let string: StringType<CurrentEnvironment> = Uniform::rand(&mut rng);
49
50            // Add the new random value to the set.
51            map.entry(string).and_modify(|count| *count += 1).or_insert(1);
52        }
53        for (string, count) in map {
54            let allowed_occurences = 1 + ITERATIONS / (string.len() * 10);
55            assert!(count <= allowed_occurences, "Encountered an element with a count of {}: {}", count, string);
56        }
57    }
58}
snarkvm_console_types_string/random.rs

snarkvm_console_types_string/
random.rs
