refactor: extract mod into file

Author: josecelano

src/shared/crypto.rs

@@ -0,0 +1,8 @@
+use rand::rngs::ThreadRng;
+use rand::Rng;
+
+pub type Seed = [u8; 32];
+
+lazy_static! {
+    pub static ref RANDOM_SEED: Seed = Rng::gen(&mut ThreadRng::default());
+}

src/shared/crypto/ephemeral_instance_keys.rs

@@ -0,0 +1,95 @@
+pub mod seeds {
+    use self::detail::CURRENT_SEED;
+    use crate::shared::crypto::ephemeral_instance_keys::{Seed, RANDOM_SEED};
+
+    pub trait Keeper {
+        type Seed: Sized + Default + AsMut<[u8]>;
+        fn get_seed() -> &'static Self::Seed;
+    }
+
+    pub struct Instance;
+    pub struct Current;
+
+    impl Keeper for Instance {
+        type Seed = Seed;
+
+        fn get_seed() -> &'static Self::Seed {
+            &RANDOM_SEED
+        }
+    }
+
+    impl Keeper for Current {
+        type Seed = Seed;
+
+        #[allow(clippy::needless_borrow)]
+        fn get_seed() -> &'static Self::Seed {
+            &CURRENT_SEED
+        }
+    }
+
+    #[cfg(test)]
+    mod tests {
+        use super::detail::ZEROED_TEST_SEED;
+        use super::{Current, Instance, Keeper};
+        use crate::shared::crypto::ephemeral_instance_keys::Seed;
+
+        pub struct ZeroedTestSeed;
+
+        impl Keeper for ZeroedTestSeed {
+            type Seed = Seed;
+
+            #[allow(clippy::needless_borrow)]
+            fn get_seed() -> &'static Self::Seed {
+                &ZEROED_TEST_SEED
+            }
+        }
+
+        #[test]
+        fn the_default_seed_and_the_zeroed_seed_should_be_the_same_when_testing() {
+            assert_eq!(Current::get_seed(), ZeroedTestSeed::get_seed());
+        }
+
+        #[test]
+        fn the_default_seed_and_the_instance_seed_should_be_different_when_testing() {
+            assert_ne!(Current::get_seed(), Instance::get_seed());
+        }
+    }
+
+    mod detail {
+        use crate::shared::crypto::ephemeral_instance_keys::Seed;
+
+        #[allow(dead_code)]
+        pub const ZEROED_TEST_SEED: &Seed = &[0u8; 32];
+
+        #[cfg(test)]
+        pub use ZEROED_TEST_SEED as CURRENT_SEED;
+
+        #[cfg(not(test))]
+        pub use crate::shared::crypto::ephemeral_instance_keys::RANDOM_SEED as CURRENT_SEED;
+
+        #[cfg(test)]
+        mod tests {
+            use std::convert::TryInto;
+
+            use crate::shared::crypto::ephemeral_instance_keys::RANDOM_SEED;
+            use crate::shared::crypto::keys::seeds::detail::ZEROED_TEST_SEED;
+            use crate::shared::crypto::keys::seeds::CURRENT_SEED;
+
+            #[test]
+            fn it_should_have_a_zero_test_seed() {
+                assert_eq!(*ZEROED_TEST_SEED, [0u8; 32]);
+            }
+
+            #[test]
+            fn it_should_default_to_zeroed_seed_when_testing() {
+                assert_eq!(*CURRENT_SEED, *ZEROED_TEST_SEED);
+            }
+
+            #[test]
+            fn it_should_have_a_large_random_seed() {
+                assert!(u128::from_ne_bytes((*RANDOM_SEED)[..16].try_into().unwrap()) > u128::from(u64::MAX));
+                assert!(u128::from_ne_bytes((*RANDOM_SEED)[16..].try_into().unwrap()) > u128::from(u64::MAX));
+            }
+        }
+    }
+}

src/shared/crypto/keys.rs

@@ -0,0 +1,2 @@
+pub mod ephemeral_instance_keys;
+pub mod keys;