style: improve use of std api

- replace get(0) by first()
lint message: accessing first element with `objs.get(0)`
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#get_first
- use io::Error::other method available since Rust 1.87
lint message: this can be `std::io::Error::other(_)`
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#io_other_error
- implement From<_> instead of Into<_>
lint message: an implementation of `From` is preferred since it gives you `Into<_>` for free where the reverse isn't true
help: `impl From<Local> for Foreign` is allowed by the orphan rules, for more information see
            https://doc.rust-lang.org/reference/items/implementations.html#trait-implementation-coherence
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#from_over_into
- use next_back instead of rev + next
lint message: manual backwards iteration
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#manual_next_back
- use saturating_sub instead of manual implement it
lint message: manual arithmetic check found
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#implicit_saturating_sub
- add Default implementation for Checksummer
use derived Default ans use it in new, as new set all value to None
lint message: you should consider adding a `Default` implementation for `Checksummer`
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#new_without_default
- use `any` instead of `find` + `is_some`
lint message: called `is_some()` after searching an `Iterator` with `find`
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#search_is_some
- replace `and_then` + `Some(_)` with `map`
lint message: using `Option.and_then(|x| Some(y))`, which is more succinctly expressed as `map(|x| y)`
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#bind_instead_of_map
- replace `skip_while` + `next` with `find`
lint message: called `skip_while(<p>).next()` on an `Iterator`
help: this is more succinctly expressed by calling `.find(!<p>)` instead
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#skip_while_next
- use `matches!` instead of manual implementation
lint message: match expression looks like `matches!` macro
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#match_like_matches_macro
- use `keys` and `values methods insteads of iterating and ignoring either the keys or values.
help: for further information visit https://rust-lang.github.io/rust-clippy/rust-1.92.0/index.html#iter_kv_map

src/net/client.rs

@@ -180,8 +180,7 @@ impl ClientConn {
 				"Too many inflight requests! RequestID collision. Interrupting previous request."
 			);
 			let _ = old_ch.send(Box::pin(futures::stream::once(async move {
-				Err(std::io::Error::new(
-					std::io::ErrorKind::Other,
+				Err(std::io::Error::other(
 					"RequestID collision, too many inflight requests",
 				))
 			})));

src/net/message.rs

@@ -493,10 +493,7 @@ impl RespEnc {
 				(res_stream, order_tag)
 			}
 			Err(err) => {
-				let err = std::io::Error::new(
-					std::io::ErrorKind::Other,
-					format!("netapp error: {}", err),
-				);
+				let err = std::io::Error::other(format!("netapp error: {}", err));
 				(
 					Box::pin(futures::stream::once(async move { Err(err) })),
 					None,

src/net/recv.rs

@@ -62,7 +62,7 @@ pub(crate) trait RecvLoop: Sync + 'static {
 			trace!(
 				"recv_loop({}): in_progress = {:?}",
 				debug_name,
-				streams.iter().map(|(id, _)| id).collect::<Vec<_>>()
+				streams.keys().collect::<Vec<_>>()
 			);
 
 			let mut header_id = [0u8; RequestID::BITS as usize / 8];
@@ -79,10 +79,7 @@ pub(crate) trait RecvLoop: Sync + 'static {
 
 			if size == CANCEL_REQUEST {
 				if let Some(mut stream) = streams.remove(&id) {
-					stream.send(Err(std::io::Error::new(
-						std::io::ErrorKind::Other,
-						"netapp: cancel requested",
-					)));
+					stream.send(Err(std::io::Error::other("netapp: cancel requested")));
 					stream.end();
 				}
 				self.cancel_handler(id);