Fix all clippy warnings

core/src/lib.rs

@@ -103,6 +103,9 @@ impl Machine {
 	}
 
 	/// Copy and get the return value of the machine, if any.
+	#[allow(clippy::slow_vector_initialization)]
+	// Clippy complains about not using `no_std`. However, we need to support
+	// `no_std` and we can't use that.
 	pub fn return_value(&self) -> Vec<u8> {
 		if self.return_range.start > U256::from(usize::MAX) {
 			let mut ret = Vec::new();

core/src/memory.rs

@@ -48,9 +48,8 @@ impl Memory {
 		&self.data
 	}
 
-	/// Resize the memory, making it cover the memory region of `offset..(offset
-	/// + len)`, with 32 bytes as the step. If the length is zero, this function
-	/// does nothing.
+	/// Resize the memory, making it cover the memory region of `offset..(offset + len)`,
+	/// with 32 bytes as the step. If the length is zero, this function does nothing.
 	pub fn resize_offset(&mut self, offset: U256, len: U256) -> Result<(), ExitError> {
 		if len == U256::zero() {
 			return Ok(());
@@ -79,6 +78,9 @@ impl Memory {
 	///
 	/// Value of `size` is considered trusted. If they're too large,
 	/// the program can run out of memory, or it can overflow.
+	#[allow(clippy::slow_vector_initialization)]
+	// Clippy complains about not using `vec!`. However, we need to support
+	// `no_std` and we can't use that.
 	pub fn get(&self, offset: usize, size: usize) -> Vec<u8> {
 		let mut ret = Vec::new();
 		ret.resize(size, 0);

gasometer/src/lib.rs

@@ -778,7 +778,7 @@ struct Inner<'config> {
 	config: &'config Config,
 }
 
-impl<'config> Inner<'config> {
+impl Inner<'_> {
 	fn memory_gas(&self, memory: MemoryCost) -> Result<u64, ExitError> {
 		let from = memory.offset;
 		let len = memory.len;

src/backend/memory.rs

@@ -88,7 +88,7 @@ impl<'vicinity> MemoryBackend<'vicinity> {
 	}
 }
 
-impl<'vicinity> Backend for MemoryBackend<'vicinity> {
+impl Backend for MemoryBackend<'_> {
 	fn gas_price(&self) -> U256 {
 		self.vicinity.gas_price
 	}
@@ -172,7 +172,7 @@ impl<'vicinity> Backend for MemoryBackend<'vicinity> {
 	}
 }
 
-impl<'vicinity> ApplyBackend for MemoryBackend<'vicinity> {
+impl ApplyBackend for MemoryBackend<'_> {
 	fn apply<A, I, L>(&mut self, values: A, logs: L, delete_empty: bool)
 	where
 		A: IntoIterator<Item = Apply<I>>,
@@ -189,7 +189,7 @@ impl<'vicinity> ApplyBackend for MemoryBackend<'vicinity> {
 					reset_storage,
 				} => {
 					let is_empty = {
-						let account = self.state.entry(address).or_insert_with(Default::default);
+						let account = self.state.entry(address).or_default();
 						account.balance = basic.balance;
 						account.nonce = basic.nonce;
 						if let Some(code) = code {

src/executor/stack/executor.rs

@@ -672,7 +672,7 @@ impl<'config, 'precompiles, S: StackState<'config>, P: PrecompileSet>
 				let mut stream = rlp::RlpStream::new_list(2);
 				stream.append(&caller);
 				stream.append(&nonce);
-				H256::from_slice(Keccak256::digest(&stream.out()).as_slice()).into()
+				H256::from_slice(Keccak256::digest(stream.out()).as_slice()).into()
 			}
 			CreateScheme::Fixed(naddress) => naddress,
 		}
@@ -1087,8 +1087,8 @@ impl<'config, 'precompiles, S: StackState<'config>, P: PrecompileSet>
 pub struct StackExecutorCallInterrupt<'borrow>(TaggedRuntime<'borrow>);
 pub struct StackExecutorCreateInterrupt<'borrow>(TaggedRuntime<'borrow>);
 
-impl<'config, 'precompiles, S: StackState<'config>, P: PrecompileSet> Handler
-	for StackExecutor<'config, 'precompiles, S, P>
+impl<'config, S: StackState<'config>, P: PrecompileSet> Handler
+	for StackExecutor<'config, '_, S, P>
 {
 	type CreateInterrupt = StackExecutorCreateInterrupt<'static>;
 	type CreateFeedback = Infallible;
@@ -1397,8 +1397,8 @@ struct StackExecutorHandle<'inner, 'config, 'precompiles, S, P> {
 	is_static: bool,
 }
 
-impl<'inner, 'config, 'precompiles, S: StackState<'config>, P: PrecompileSet> PrecompileHandle
-	for StackExecutorHandle<'inner, 'config, 'precompiles, S, P>
+impl<'config, S: StackState<'config>, P: PrecompileSet> PrecompileHandle
+	for StackExecutorHandle<'_, 'config, '_, S, P>
 {
 	// Perform subcall in provided context.
 	/// Precompile specifies in which context the subcall is executed.

src/executor/stack/memory.rs

@@ -441,7 +441,7 @@ pub struct MemoryStackState<'backend, 'config, B> {
 	substate: MemoryStackSubstate<'config>,
 }
 
-impl<'backend, 'config, B: Backend> Backend for MemoryStackState<'backend, 'config, B> {
+impl<B: Backend> Backend for MemoryStackState<'_, '_, B> {
 	fn gas_price(&self) -> U256 {
 		self.backend.gas_price()
 	}
@@ -515,7 +515,7 @@ impl<'backend, 'config, B: Backend> Backend for MemoryStackState<'backend, 'conf
 	}
 }
 
-impl<'backend, 'config, B: Backend> StackState<'config> for MemoryStackState<'backend, 'config, B> {
+impl<'config, B: Backend> StackState<'config> for MemoryStackState<'_, 'config, B> {
 	fn metadata(&self) -> &StackSubstateMetadata<'config> {
 		self.substate.metadata()
 	}

src/maybe_borrowed.rs

@@ -13,7 +13,7 @@ pub enum MaybeBorrowed<'a, T> {
 	Owned(T),
 }
 
-impl<'a, T> core::ops::Deref for MaybeBorrowed<'a, T> {
+impl<T> core::ops::Deref for MaybeBorrowed<'_, T> {
 	type Target = T;
 
 	fn deref(&self) -> &Self::Target {
@@ -24,7 +24,7 @@ impl<'a, T> core::ops::Deref for MaybeBorrowed<'a, T> {
 	}
 }
 
-impl<'a, T> core::ops::DerefMut for MaybeBorrowed<'a, T> {
+impl<T> core::ops::DerefMut for MaybeBorrowed<'_, T> {
 	fn deref_mut(&mut self) -> &mut Self::Target {
 		match self {
 			Self::Borrowed(x) => x,