Switch to Rust 2018 edition.

Cargo.toml

@@ -2,7 +2,7 @@
 name = "poagov"
 version = "1.0.0"
 authors = ["DrPeterVanNostrand <jnz@riseup.net>"]
-# edition = "2018"
+edition = "2018"
 readme = "README.md"
 license = "GPL-3.0"
 repository = "https://github.com/poanetwork/poa-governance-notifications"

README.md

@@ -49,7 +49,7 @@ To build the `poagov` CLI tool, run the following:
     $ cd poa-governance-notifications
     $ cargo build --release
 
-`poagov` can be built with Rust 1.29.1-stable or later and requires `libssl`;
+`poagov` can be built with Rust 1.31.0-stable or later and requires `libssl`;
 see the following "Requires libssl" section for more information.
 
 ### Testing

src/blockchain.rs

@@ -5,9 +5,9 @@ use std::time::Duration;
 
 use web3::types::BlockNumber;
 
-use client::RpcClient;
-use config::{Config, StartBlock};
-use error::{Error, Result};
+use crate::client::RpcClient;
+use crate::config::{Config, StartBlock};
+use crate::error::{Error, Result};
 
 fn sleep_or_ctrlc(n_secs: u64, running: Arc<AtomicBool>) -> Option<()> {
     let done_sleeping = Arc::new(AtomicBool::new(false));

src/cli.rs

@@ -1,3 +1,4 @@
+// Some of `Cli`'s methods are not currently being used.
 #![allow(dead_code)]
 
 use clap::{ArgMatches, App};

src/client.rs

@@ -1,17 +1,13 @@
 use std::u64;
 
-use ethabi;
-use hex;
 use jsonrpc_core as json_rpc;
-use reqwest;
 use serde_json as json;
-use web3;
 use web3::types::{Address, BlockNumber, Filter, FilterBuilder, U256};
 
-use config::{ContractType, PoaContract};
-use error::{Error, Result};
-use response::{v1, v2};
-use response::common::BallotCreatedLog;
+use crate::config::{ContractType, PoaContract};
+use crate::error::{Error, Result};
+use crate::response::{v1, v2};
+use crate::response::common::BallotCreatedLog;
 
 #[derive(Debug)]
 pub enum RpcMethod {
@@ -212,9 +208,9 @@ mod tests {
 
     use web3::types::BlockNumber;
 
-    use super::super::tests::setup;
+    use crate::tests::setup;
+    use crate::config::{ContractType, ContractVersion, Network, PoaContract};
     use super::RpcClient;
-    use config::{ContractType, ContractVersion, Network, PoaContract};
 
     #[test]
     fn test_get_last_mined_block() {

src/config.rs

@@ -1,13 +1,13 @@
 use std::env;
 use std::fmt::{self, Debug, Formatter};
 use std::fs::File;
-use std::str::FromStr;
+use std::str::FromStr as _FromStr;
 
 use ethabi::{Address, Contract, Event, Function};
 
-use cli::Cli;
-use error::{Error, Result};
-use response::common::BallotType;
+use crate::cli::Cli;
+use crate::error::{Error, Result};
+use crate::response::common::BallotType;
 
 const DEFAULT_BLOCK_TIME_SECS: u64 = 30;
 

src/error.rs

@@ -1,11 +1,3 @@
-use ctrlc;
-use jsonrpc_core;
-use ethabi;
-use failure;
-use lettre;
-use native_tls;
-use reqwest;
-
 pub type Result<T> = ::std::result::Result<T, Error>;
 
 #[derive(Debug)]

src/logger.rs

@@ -1,23 +1,26 @@
-use std::fs::{self, create_dir, File, read_dir, remove_file};
+use std::fs::{self, create_dir, read_dir, remove_file, File};
 use std::io::stderr;
 use std::path::Path;
 
-use chrono::{DateTime, TimeZone, Utc};
-use slog::{self, Drain};
+use chrono::{DateTime, TimeZone as _TimeZone, Utc};
+use slog::{info, o, warn, Drain as _Drain};
 use slog_term::{FullFormat, PlainSyncDecorator};
 use web3::types::BlockNumber;
 
-use config::Config;
-use error::Error;
-use notify::Notification;
+use crate::config::Config;
+use crate::error::Error;
+use crate::notify::Notification;
 
 // The date format used to name log files; e.g. "Oct-08-2018-14:09:00".
 const FILE_NAME_DATE_FORMAT: &str = "%b-%d-%Y-%H:%M:%S";
+
 // The directory (relative to Cargo.toml) to store logs.
 const LOGS_DIR: &str = "logs";
+
 const MAX_NUMBER_OF_LOG_FILES: usize = 3;
 const MAX_LOG_FILE_SIZE_MB: usize = 4;
 const MAX_LOG_FILE_SIZE_BYTES: usize = MAX_LOG_FILE_SIZE_MB * 1024 * 1024;
+
 // We dont want to check the log file's size after every log that is written, this constant states
 // "after this many logs have been written, check the log file's size". This value assumes an
 // average log is around 100 ASCII characters (bytes) long.

src/main.rs

@@ -1,24 +1,3 @@
-extern crate chrono;
-extern crate clap;
-extern crate ctrlc;
-extern crate dotenv;
-extern crate ethabi;
-extern crate ethereum_types;
-extern crate failure;
-extern crate hex;
-extern crate jsonrpc_core;
-#[macro_use]
-extern crate lazy_static;
-extern crate lettre;
-extern crate lettre_email;
-extern crate native_tls;
-extern crate reqwest;
-extern crate serde_json;
-#[macro_use]
-extern crate slog;
-extern crate slog_term;
-extern crate web3;
-
 mod blockchain;
 mod cli;
 mod client;
@@ -31,13 +10,15 @@ mod response;
 use std::sync::{Arc, Mutex};
 use std::sync::atomic::{AtomicBool, Ordering};
 
-use blockchain::BlockchainIter;
-use cli::parse_cli;
-use client::RpcClient;
-use config::{Config, ContractVersion};
-use error::{Error, Result};
-use logger::Logger;
-use notify::{Notification, Notifier};
+use lazy_static::lazy_static;
+
+use crate::blockchain::BlockchainIter;
+use crate::cli::parse_cli;
+use crate::client::RpcClient;
+use crate::config::{Config, ContractVersion};
+use crate::error::{Error, Result};
+use crate::logger::Logger;
+use crate::notify::{Notification, Notifier};
 
 lazy_static! {
     // Tracks whether or not the environment variables have been loaded from the .env file.

src/notify.rs

@@ -1,18 +1,18 @@
 use std::sync::{Arc, Mutex};
 
-use lettre::{SendableEmail, Transport};
+use lettre::{SendableEmail, Transport as _Transport};
 use lettre::smtp::{ClientSecurity, ConnectionReuseParameters, SmtpClient, SmtpTransport};
 use lettre::smtp::authentication::{Credentials, Mechanism};
 use lettre::smtp::client::net::ClientTlsParameters;
 use lettre_email::{Email, EmailBuilder};
 use native_tls::TlsConnector;
 
-use config::Config;
-use error::{Error, Result};
-use logger::Logger;
-use response::common::BallotCreatedLog;
-use response::v1::VotingState;
-use response::v2::BallotInfo;
+use crate::config::Config;
+use crate::error::{Error, Result};
+use crate::logger::Logger;
+use crate::response::common::BallotCreatedLog;
+use crate::response::v1::VotingState;
+use crate::response::v2::BallotInfo;
 
 #[derive(Clone, Debug)]
 pub enum Notification<'a> {
@@ -37,7 +37,7 @@ impl<'a> Notification<'a> {
     {
         Notification::VotingState { config, log, voting_state }
     }
-    
+
     pub fn from_ballot_info(
         config: &'a Config,
         log: BallotCreatedLog,
@@ -79,7 +79,7 @@ impl<'a> Notification<'a> {
             Notification::BallotInfo { log, .. } => log,
         }
     }
-    
+
     fn contract_name(&self) -> String {
         match self {
             Notification::VotingState { voting_state, .. } => voting_state.contract_name(),

src/response/common.rs

@@ -5,7 +5,7 @@ use chrono::{DateTime, NaiveDateTime, Utc};
 use ethabi;
 use web3::types::{Address, H256, U256};
 
-use error::{Error, Result};
+use crate::error::{Error, Result};
 
 /// Converts a `U256` timestamp to a UTC `DateTime`.
 pub fn u256_to_datetime(uint: U256) -> DateTime<Utc> {

src/response/v1.rs

@@ -2,7 +2,7 @@ use chrono::{DateTime, Utc};
 use ethabi;
 use web3::types::{Address, U256};
 
-use response::common::{u256_to_datetime, BallotType, KeyType};
+use crate::response::common::{u256_to_datetime, BallotType, KeyType};
 
 /// Describes the current state of a given ballot.
 ///

src/response/v2.rs

@@ -2,7 +2,7 @@ use chrono::{DateTime, Utc};
 use ethabi;
 use web3::types::{Address, U256};
 
-use response::common::{u256_to_datetime, BallotType, KeyType};
+use crate::response::common::{u256_to_datetime, BallotType, KeyType};
 
 #[derive(Clone, Debug)]
 pub enum BallotInfo {