Use crate::prelude::* rather than specific imports

New rustc beta now warns on duplicate imports when one of the
imports is from a wildcard import or the default prelude. Thus, to
avoid this here we prefer to always use `crate::prelude::*` and let
it decide if we actually need to import anything.

Author: TheBlueMatt

lightning/src/chain/chaininterface.rs

@@ -14,7 +14,8 @@
 //! disconnections, transaction broadcasting, and feerate information requests.
 
 use core::{cmp, ops::Deref};
-use core::convert::TryInto;
+
+use crate::prelude::*;
 
 use bitcoin::blockdata::transaction::Transaction;
 

lightning/src/chain/channelmonitor.rs

@@ -56,7 +56,6 @@ use crate::events::bump_transaction::{AnchorDescriptor, BumpTransactionEvent};
 use crate::prelude::*;
 use core::{cmp, mem};
 use crate::io::{self, Error};
-use core::convert::TryInto;
 use core::ops::Deref;
 use crate::sync::{Mutex, LockTestExt};
 

lightning/src/routing/gossip.rs

@@ -38,7 +38,6 @@ use crate::io;
 use crate::io_extras::{copy, sink};
 use crate::prelude::*;
 use core::{cmp, fmt};
-use core::convert::TryFrom;
 use crate::sync::{RwLock, RwLockReadGuard, LockTestExt};
 #[cfg(feature = "std")]
 use core::sync::atomic::{AtomicUsize, Ordering};

lightning/src/util/errors.rs

@@ -10,8 +10,8 @@
 //! Error types live here.
 
 use crate::ln::script::ShutdownScript;
+use crate::prelude::*;
 
-use alloc::string::String;
 use core::fmt;
 
 /// Indicates an error on the client's part (usually some variant of attempting to use too-low or

lightning/src/util/indexed_map.rs

@@ -1,7 +1,6 @@
 //! This module has a map which can be iterated in a deterministic order. See the [`IndexedMap`].
 
 use crate::prelude::*;
-use alloc::vec::Vec;
 use alloc::slice::Iter;
 use core::hash::Hash;
 use core::cmp::Ord;

lightning/src/util/persist.rs

@@ -9,13 +9,11 @@
 //! and [`ChannelMonitor`] all in one place.
 
 use core::cmp;
-use core::convert::{TryFrom, TryInto};
 use core::ops::Deref;
 use core::str::FromStr;
 use bitcoin::{BlockHash, Txid};
 
 use crate::{io, log_error};
-use crate::alloc::string::ToString;
 use crate::prelude::*;
 
 use crate::chain;

lightning/src/util/ser.rs

@@ -19,7 +19,6 @@ use crate::io_extras::{copy, sink};
 use core::hash::Hash;
 use crate::sync::{Mutex, RwLock};
 use core::cmp;
-use core::convert::TryFrom;
 use core::ops::Deref;
 
 use alloc::collections::BTreeMap;
@@ -35,7 +34,6 @@ use bitcoin::{consensus, Witness};
 use bitcoin::consensus::Encodable;
 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
 use bitcoin::hash_types::{Txid, BlockHash};
-use core::marker::Sized;
 use core::time::Duration;
 use crate::chain::ClaimId;
 use crate::ln::msgs::DecodeError;