Fix nightly (#169)

* Fix nightly lint causing compilation to fail

* Relax checks on unused imports

This is definitely worth a warning but should not make builds fail for
users. We deny warnings in CI and sort this out before integrating.

See issue #169 for more details.

* Don't let nightly builds fail CI

* Clean up superfluous explicit import

Current nightly considers use nix::self as an unused import as nix is
already through the extern prelude (since edition 2018) and generates a
warning. Remove the explicit import to silence it.

See:

* Output of 'cargo --verbose check'
* https://doc.rust-lang.org/stable/reference/names/preludes.html#extern-prelude

---------

Co-authored-by: Ross Smyth <rsmyth@electrocraft.com>
Co-authored-by: Christian Meusel <christian.meusel@posteo.de>

.github/workflows/build.yaml

@@ -18,6 +18,9 @@ on:
       toolchain:
         default: stable
         type: string
+      continue-on-error:
+        default: false
+        type: boolean
 
 env:
   # While we could define these on a per-job basis, there's no harm in simply
@@ -46,10 +49,13 @@ env:
   CARGO_TERM_COLOR: always
   # Enable cross compilation for `pkg_config`.
   PKG_CONFIG_ALLOW_CROSS: 1
+  # Deny warnings.
+  RUSTFLAGS: -D warnings
 
 jobs:
   build:
     runs-on: ${{ inputs.runs_on }}
+    continue-on-error: ${{ inputs.continue-on-error }}
     steps:
       - name: Build | install dependencies
         if: inputs.runs_on == 'ubuntu-latest'

.github/workflows/ci.yaml

@@ -244,3 +244,31 @@ jobs:
       disable_extra_builds: true
       disable_tests: true
       target: x86_64-unknown-netbsd
+
+  # --------------------------------------------------------------------------
+  # NIGHTLY BUILD
+
+  aarch64-apple-darwin-nightly:
+    uses: ./.github/workflows/build.yaml
+    with:
+      continue-on-error: true
+      disable_tests: true
+      runs_on: macos-latest
+      target: aarch64-apple-darwin
+      toolchain: nightly
+
+  x86_64-pc-windows-msvc-nightly:
+    uses: ./.github/workflows/build.yaml
+    with:
+      continue-on-error: true
+      runs_on: windows-2019
+      target: x86_64-pc-windows-msvc
+      toolchain: nightly
+
+  x86_64-unknown-linux-gnu-nightly:
+    uses: ./.github/workflows/build.yaml
+    with:
+      continue-on-error: true
+      extra_packages: libudev-dev
+      target: x86_64-unknown-linux-gnu
+      toolchain: nightly

src/lib.rs

@@ -19,8 +19,7 @@
 #![deny(
     missing_docs,
     missing_debug_implementations,
-    missing_copy_implementations,
-    unused
+    missing_copy_implementations
 )]
 // Document feature-gated elements on docs.rs. See
 // https://doc.rust-lang.org/rustdoc/unstable-features.html?highlight=doc(cfg#doccfg-recording-what-platforms-or-features-are-required-for-code-to-be-present
@@ -32,7 +31,6 @@
 // doc tests.
 #![doc(test(attr(allow(unused_must_use))))]
 
-use std::convert::From;
 use std::error::Error as StdError;
 use std::fmt;
 use std::io;

src/posix/tty.rs

@@ -5,7 +5,7 @@ use std::time::Duration;
 use std::{io, mem};
 
 use nix::fcntl::{fcntl, OFlag};
-use nix::{self, libc, unistd};
+use nix::{libc, unistd};
 
 use crate::posix::ioctl::{self, SerialLines};
 use crate::posix::termios;