Merge rust-bitcoin/rust-bitcoin#3473: Fix lint errors

8696cb4b07 Fix unused import warning (Jamil Lambert, PhD)
fbc7aa7fd5 Remove unnecessary lifetimes (Jamil Lambert, PhD)

Pull request description:

  New lint warnings from a recent nightly toolchain show some explicit lifetimes that can be omitted.

  The unnecessary lifetimes have been removed.

  An unused import warning has also been fixed by placing the use statement behind the relevant feature gate.

ACKs for top commit:
  tcharding:
    ACK 8696cb4b07
  apoelstra:
    ACK 8696cb4b07 successfully ran local tests

Tree-SHA512: 37e14ca9be2e8cfa64498084a7363783c2cca92dfce40a0a3ed9bda98f081c1fa9119e5d49d81684b6968329945c7004b86534412fd2fcd4898b862c859d42c6

bitcoin/src/sign_message.rs

@@ -6,6 +6,7 @@
 //! library is used with the `secp-recovery` feature.
 
 use hashes::{sha256d, HashEngine};
+#[cfg(feature = "secp-recovery")]
 use secp256k1::SecretKey;
 
 use crate::consensus::encode::WriteExt;

io/src/lib.rs

@@ -98,7 +98,7 @@ pub struct Take<'a, R: Read + ?Sized> {
     remaining: u64,
 }
 
-impl<'a, R: Read + ?Sized> Take<'a, R> {
+impl<R: Read + ?Sized> Take<'_, R> {
     /// Reads all bytes until EOF from the underlying reader into `buf`.
     #[cfg(feature = "alloc")]
     #[inline]
@@ -120,7 +120,7 @@ impl<'a, R: Read + ?Sized> Take<'a, R> {
     }
 }
 
-impl<'a, R: Read + ?Sized> Read for Take<'a, R> {
+impl<R: Read + ?Sized> Read for Take<'_, R> {
     #[inline]
     fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
         let len = cmp::min(buf.len(), self.remaining.try_into().unwrap_or(buf.len()));
@@ -131,7 +131,7 @@ impl<'a, R: Read + ?Sized> Read for Take<'a, R> {
 }
 
 // Impl copied from Rust stdlib.
-impl<'a, R: BufRead + ?Sized> BufRead for Take<'a, R> {
+impl<R: BufRead + ?Sized> BufRead for Take<'_, R> {
     #[inline]
     fn fill_buf(&mut self) -> Result<&[u8]> {
         // Don't call into inner reader at all at EOF because it may still block
@@ -299,7 +299,7 @@ impl Write for alloc::vec::Vec<u8> {
     fn flush(&mut self) -> Result<()> { Ok(()) }
 }
 
-impl<'a> Write for &'a mut [u8] {
+impl Write for &mut [u8] {
     #[inline]
     fn write(&mut self, buf: &[u8]) -> Result<usize> {
         let cnt = core::cmp::min(self.len(), buf.len());

units/src/fee_rate.rs

@@ -163,7 +163,7 @@ impl Add<&FeeRate> for FeeRate {
     fn add(self, other: &FeeRate) -> <FeeRate as Add>::Output { FeeRate(self.0 + other.0) }
 }
 
-impl<'a, 'b> Add<&'a FeeRate> for &'b FeeRate {
+impl<'a> Add<&'a FeeRate> for &FeeRate {
     type Output = FeeRate;
 
     fn add(self, other: &'a FeeRate) -> <FeeRate as Add>::Output { FeeRate(self.0 + other.0) }
@@ -187,7 +187,7 @@ impl Sub<&FeeRate> for FeeRate {
     fn sub(self, other: &FeeRate) -> <FeeRate as Add>::Output { FeeRate(self.0 - other.0) }
 }
 
-impl<'a, 'b> Sub<&'a FeeRate> for &'b FeeRate {
+impl<'a> Sub<&'a FeeRate> for &FeeRate {
     type Output = FeeRate;
 
     fn sub(self, other: &'a FeeRate) -> <FeeRate as Add>::Output { FeeRate(self.0 - other.0) }