diff --git a/src/bank.rs b/src/bank.rs
index 8fee843eb6602a..3a7c7540e8f5c3 100644
--- a/src/bank.rs
+++ b/src/bank.rs
@@ -24,9 +24,9 @@ pub const MAX_ENTRY_IDS: usize = 1024 * 4;
 
 #[derive(Debug, PartialEq, Eq)]
 pub enum BankError {
-    AccountNotFound,
-    InsufficientFunds,
-    InvalidTransferSignature,
+    AccountNotFound(PublicKey),
+    InsufficientFunds(PublicKey),
+    InvalidTransferSignature(Signature),
 }
 
 pub type Result<T> = result::Result<T, BankError>;
@@ -167,11 +167,11 @@ impl Bank {
         let option = bals.get(&tr.from);
 
         if option.is_none() {
-            return Err(BankError::AccountNotFound);
+            return Err(BankError::AccountNotFound(tr.from));
         }
 
         if !self.reserve_signature_with_last_id(&tr.sig, &tr.last_id) {
-            return Err(BankError::InvalidTransferSignature);
+            return Err(BankError::InvalidTransferSignature(tr.sig));
         }
 
         loop {
@@ -180,7 +180,7 @@ impl Bank {
 
             if current < tr.contract.tokens {
                 self.forget_signature_with_last_id(&tr.sig, &tr.last_id);
-                return Err(BankError::InsufficientFunds);
+                return Err(BankError::InsufficientFunds(tr.from));
             }
 
             let result = bal.compare_exchange(
@@ -427,9 +427,10 @@ mod tests {
     fn test_account_not_found() {
         let mint = Mint::new(1);
         let bank = Bank::new(&mint);
+        let keypair = KeyPair::new();
         assert_eq!(
-            bank.transfer(1, &KeyPair::new(), mint.pubkey(), mint.last_id()),
-            Err(BankError::AccountNotFound)
+            bank.transfer(1, &keypair, mint.pubkey(), mint.last_id()),
+            Err(BankError::AccountNotFound(keypair.pubkey()))
         );
         assert_eq!(bank.transaction_count(), 0);
     }
@@ -444,7 +445,7 @@ mod tests {
         assert_eq!(bank.transaction_count(), 1);
         assert_eq!(
             bank.transfer(10_001, &mint.keypair(), pubkey, mint.last_id()),
-            Err(BankError::InsufficientFunds)
+            Err(BankError::InsufficientFunds(mint.pubkey()))
         );
         assert_eq!(bank.transaction_count(), 1);
 
diff --git a/src/crdt.rs b/src/crdt.rs
index eef6981f4720dd..1393fb5a53828e 100644
--- a/src/crdt.rs
+++ b/src/crdt.rs
@@ -502,7 +502,7 @@ impl Crdt {
 }
 
 #[cfg(test)]
-mod test {
+mod tests {
     use crdt::{Crdt, ReplicatedData};
     use logger;
     use packet::Blob;
diff --git a/src/signature.rs b/src/signature.rs
index 0bb704f8000b17..1521f815f4af6b 100644
--- a/src/signature.rs
+++ b/src/signature.rs
@@ -72,27 +72,23 @@ impl GenKeys {
     pub fn gen_n_seeds(&self, n_seeds: i64) -> Vec<[u8; 16]> {
         let mut rng = self.generator.borrow_mut();
 
-        let seeds = (0..n_seeds)
+        (0..n_seeds)
             .into_iter()
-            .map(|_| {
-                let seed: [u8; 16] = rng.gen();
-                seed
-            })
-            .collect();
-        seeds
+            .map(|_| rng.gen::<[u8; 16]>())
+            .collect()
     }
 
     pub fn gen_n_keys(&self, n_keys: i64, tokens_per_user: i64) -> Vec<(Vec<u8>, i64)> {
-        let keys = self.gen_n_seeds(n_keys);
+        let seeds = self.gen_n_seeds(n_keys);
 
-        let users: Vec<_> = keys.into_par_iter()
+        seeds
+            .into_par_iter()
             .map(|seed| {
                 let new: GenKeys = GenKeys::new(&seed[..]);
                 let pkcs8 = KeyPair::generate_pkcs8(&new).unwrap().to_vec();
                 (pkcs8, tokens_per_user)
             })
-            .collect();
-        users
+            .collect()
     }
 }
 
@@ -104,22 +100,12 @@ impl SecureRandom for GenKeys {
     }
 }
 
-#[cfg(all(feature = "unstable", test))]
+#[cfg(test)]
 mod tests {
-    extern crate test;
-
-    use self::test::Bencher;
     use super::*;
     use std::collections::HashSet;
     use std::iter::FromIterator;
 
-    #[bench]
-    fn bench_gen_keys(b: &mut Bencher) {
-        let seed: &[_] = &[1, 2, 3, 4];
-        let rnd = GenKeys::new(seed);
-        b.iter(|| rnd.gen_n_keys(1000, 1));
-    }
-
     #[test]
     fn test_new_key_is_redundant() {
         let seed: &[_] = &[1, 2, 3, 4];
@@ -145,3 +131,20 @@ mod tests {
         assert_eq!(users1_set, users2_set);
     }
 }
+
+#[cfg(all(feature = "unstable", test))]
+mod bench {
+    extern crate test;
+
+    use self::test::Bencher;
+    use super::*;
+    use std::collections::HashSet;
+    use std::iter::FromIterator;
+
+    #[bench]
+    fn bench_gen_keys(b: &mut Bencher) {
+        let seed: &[_] = &[1, 2, 3, 4];
+        let rnd = GenKeys::new(seed);
+        b.iter(|| rnd.gen_n_keys(1000, 1));
+    }
+}