It's Clippy time (#3806)

Fix some Clippy issues

substrate/core/consensus/babe/primitives/src/digest.rs

@@ -91,7 +91,7 @@ impl BabePreDigest {
 }
 
 /// The prefix used by BABE for its VRF keys.
-pub const BABE_VRF_PREFIX: &'static [u8] = b"substrate-babe-vrf";
+pub const BABE_VRF_PREFIX: &[u8] = b"substrate-babe-vrf";
 
 /// A raw version of `BabePreDigest`, usable on `no_std`.
 #[derive(Copy, Clone, Encode, Decode)]

substrate/core/consensus/babe/src/aux_schema.rs

@@ -38,7 +38,7 @@ fn load_decode<B, T>(backend: &B, key: &[u8]) -> ClientResult<Option<T>>
 		T: Decode,
 {
 	let corrupt = |e: codec::Error| {
-		ClientError::Backend(format!("BABE DB is corrupted. Decode error: {}", e.what())).into()
+		ClientError::Backend(format!("BABE DB is corrupted. Decode error: {}", e.what()))
 	};
 	match backend.get_aux(key)? {
 		None => Ok(None),

substrate/core/consensus/slots/src/aux_schema.rs

@@ -38,7 +38,7 @@ fn load_decode<C, T>(backend: &C, key: &[u8]) -> ClientResult<Option<T>>
 		None => Ok(None),
 		Some(t) => T::decode(&mut &t[..])
 			.map_err(
-				|e| ClientError::Backend(format!("Slots DB is corrupted. Decode error: {}", e.what())).into(),
+				|e| ClientError::Backend(format!("Slots DB is corrupted. Decode error: {}", e.what())),
 			)
 			.map(Some)
 	}

substrate/core/consensus/slots/src/lib.rs

@@ -189,9 +189,9 @@ pub trait SimpleSlotWorker<B: BlockT> {
 					logs,
 				},
 				remaining_duration,
-			).map_err(|e| consensus_common::Error::ClientImport(format!("{:?}", e)).into()),
+			).map_err(|e| consensus_common::Error::ClientImport(format!("{:?}", e))),
 			Delay::new(remaining_duration)
-				.map_err(|err| consensus_common::Error::FaultyTimer(err).into())
+				.map_err(consensus_common::Error::FaultyTimer)
 		).map(|v| match v {
 			futures::future::Either::Left((b, _)) => b.map(|b| (b, claim)),
 			futures::future::Either::Right((Ok(_), _)) =>
@@ -220,9 +220,9 @@ pub trait SimpleSlotWorker<B: BlockT> {
 			}
 
 			let (header, body) = block.deconstruct();
-			let header_num = header.number().clone();
+			let header_num = *header.number();
 			let header_hash = header.hash();
-			let parent_hash = header.parent_hash().clone();
+			let parent_hash = *header.parent_hash();
 
 			let block_import_params = block_import_params_maker(
 				header,
@@ -401,9 +401,8 @@ impl<T: Clone> SlotDuration<T> {
 				.map_err(|_| {
 					client::error::Error::Backend({
 						error!(target: "slots", "slot duration kept in invalid format");
-						format!("slot duration kept in invalid format")
+						"slot duration kept in invalid format".to_string()
 					})
-					.into()
 				}),
 			None => {
 				use sr_primitives::traits::Zero;