1 #![allow(clippy::expect_used)] 2 // Copyright 2023 Google LLC 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 16 #[cfg(test)] 17 /// A mock implementation of a CryptoRng that returns the given bytes in `values` in 18 /// sequence. 19 pub(crate) struct MockCryptoRng<'a, I: Iterator<Item = &'a u8>> { 20 pub(crate) values: I, 21 } 22 23 impl<'a, I: Iterator<Item = &'a u8>> rand::CryptoRng for MockCryptoRng<'a, I> {} 24 25 impl<'a, I: Iterator<Item = &'a u8>> rand::RngCore for MockCryptoRng<'a, I> { fill_bytes(&mut self, dest: &mut [u8])26 fn fill_bytes(&mut self, dest: &mut [u8]) { 27 for i in dest { 28 *i = *self.values.next().expect("Expecting more data in MockCryptoRng input"); 29 } 30 } 31 next_u32(&mut self) -> u3232 fn next_u32(&mut self) -> u32 { 33 let mut bytes = [0; 4]; 34 self.fill_bytes(&mut bytes); 35 u32::from_le_bytes(bytes) 36 } 37 next_u64(&mut self) -> u6438 fn next_u64(&mut self) -> u64 { 39 let mut bytes = [0; 8]; 40 self.fill_bytes(&mut bytes); 41 u64::from_le_bytes(bytes) 42 } 43 try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand::Error>44 fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand::Error> { 45 self.fill_bytes(dest); 46 Ok(()) 47 } 48 } 49