Use nightly for style check

.github/workflows/rust.yml

@@ -64,7 +64,8 @@ jobs:
       run: |
         for path in $(colcon list | awk '$3 == "(ament_cargo)" { print $2 }'); do
         cd $path
-        cargo fmt -- --check
+        rustup toolchain install nightly
+        cargo +nightly fmt -- --check
         cd -
         done
 

examples/message_demo/src/message_demo.rs

@@ -1,6 +1,4 @@
-use std::convert::TryInto;
-use std::env;
-use std::sync::Arc;
+use std::{convert::TryInto, env, sync::Arc};
 
 use anyhow::{Error, Result};
 use rosidl_runtime_rs::{seq, BoundedSequence, Message, Sequence};

examples/minimal_pub_sub/src/minimal_two_nodes.rs

@@ -1,6 +1,10 @@
-use std::env;
-use std::sync::atomic::{AtomicU32, Ordering};
-use std::sync::{Arc, Mutex};
+use std::{
+    env,
+    sync::{
+        atomic::{AtomicU32, Ordering},
+        Arc, Mutex,
+    },
+};
 
 use anyhow::{Error, Result};
 

rosidl_runtime_rs/src/sequence.rs

@@ -1,8 +1,10 @@
-use std::cmp::Ordering;
-use std::fmt::{self, Debug, Display};
-use std::hash::{Hash, Hasher};
-use std::iter::{Extend, FromIterator, FusedIterator};
-use std::ops::{Deref, DerefMut};
+use std::{
+    cmp::Ordering,
+    fmt::{self, Debug, Display},
+    hash::{Hash, Hasher},
+    iter::{Extend, FromIterator, FusedIterator},
+    ops::{Deref, DerefMut},
+};
 
 #[cfg(feature = "serde")]
 mod serde;

rosidl_runtime_rs/src/string.rs

@@ -1,14 +1,15 @@
-use std::cmp::Ordering;
-use std::ffi::CStr;
-use std::fmt::{self, Debug, Display};
-use std::hash::{Hash, Hasher};
-use std::ops::{Deref, DerefMut};
+use std::{
+    cmp::Ordering,
+    ffi::CStr,
+    fmt::{self, Debug, Display},
+    hash::{Hash, Hasher},
+    ops::{Deref, DerefMut},
+};
 
 #[cfg(feature = "serde")]
 mod serde;
 
-use crate::sequence::Sequence;
-use crate::traits::SequenceAlloc;
+use crate::{sequence::Sequence, traits::SequenceAlloc};
 
 /// A zero-terminated UTF-8 string.
 ///

rosidl_runtime_rs/src/traits.rs

@@ -15,8 +15,7 @@
 // DISTRIBUTION A. Approved for public release; distribution unlimited.
 // OPSEC #4584.
 //
-use std::borrow::Cow;
-use std::fmt::Debug;
+use std::{borrow::Cow, fmt::Debug};
 
 /// Internal trait that connects a particular `Sequence<T>` instance to generated C functions
 /// that allocate and deallocate memory.