kill some bs58 (#4316)

* kill some bs58

* fixup

core/src/chacha.rs

@@ -154,13 +154,11 @@ mod tests {
         let mut hasher = Hasher::default();
         hasher.hash(&buf[..size]);
 
-        use bs58;
         //  golden needs to be updated if blob stuff changes....
-        let golden = Hash::new(
-            &bs58::decode("5Pz5KQyNht2nqkJhVd8F9zTFxzoDvbQSzaxQbtCPiyCo")
-                .into_vec()
-                .unwrap(),
-        );
+        let golden: Hash = "5Pz5KQyNht2nqkJhVd8F9zTFxzoDvbQSzaxQbtCPiyCo"
+            .parse()
+            .unwrap();
+
         assert_eq!(hasher.result(), golden);
         remove_file(out_path).unwrap();
     }

core/tests/rpc.rs

@@ -35,10 +35,7 @@ fn test_rpc_send_tx() {
         .send()
         .unwrap();
     let json: Value = serde_json::from_str(&response.text().unwrap()).unwrap();
-    let blockhash_vec = bs58::decode(json["result"][0].as_str().unwrap())
-        .into_vec()
-        .unwrap();
-    let blockhash = Hash::new(&blockhash_vec);
+    let blockhash: Hash = json["result"][0].as_str().unwrap().parse().unwrap();
 
     info!("blockhash: {:?}", blockhash);
     let tx = system_transaction::transfer(&alice, &bob_pubkey, 20, blockhash, 0);