ci: run clippy-check action on CI (#491)

This is a follow up PR for #477 that runs clippy on CI.

* Switch from hecrj/setup-rust-action to actions-rs/toolchain

* Fix remaining clippy lints

* Switch to minimal rustup profile

* Replace warning step with clippy

* Remove #![feature(async_await)]

Author: silvanshade

.github/workflows/CI.yml

@@ -10,9 +10,10 @@ jobs:
       matrix:
         rust: [stable, 1.39.0]
     steps:
-    - uses: hecrj/setup-rust-action@v1
+    - uses: actions-rs/toolchain@v1
       with:
-        rust-version: ${{ matrix.rust }}
+        toolchain: ${{ matrix.rust }}
+        profile: minimal
     - uses: actions/checkout@master
     - name: Check
       run: cargo check --all --bins --examples --tests --benches
@@ -100,9 +101,10 @@ jobs:
       matrix:
         rust: [stable, beta, nightly, 1.39.0]
     steps:
-    - uses: hecrj/setup-rust-action@v1
+    - uses: actions-rs/toolchain@v1
       with:
-        rust-version: ${{ matrix.rust }}
+        toolchain: ${{ matrix.rust }}
+        profile: minimal
     - uses: actions/checkout@master
     - name: Build
       run: cargo build
@@ -117,9 +119,10 @@ jobs:
       matrix:
         os: [ubuntu-latest, windows-latest, macOS-latest]
     steps:
-    - uses: hecrj/setup-rust-action@v1
+    - uses: actions-rs/toolchain@v1
       with:
-        rust-version: stable
+        toolchain: stable
+        profile: minimal
     - uses: actions/checkout@master
     - name: Build
       run: cargo build
@@ -131,9 +134,10 @@ jobs:
     needs: check
     runs-on: ubuntu-latest
     steps:
-    - uses: hecrj/setup-rust-action@v1
+    - uses: actions-rs/toolchain@v1
       with:
-        rust-version: stable
+        toolchain: stable
+        profile: minimal
     - uses: actions/checkout@master
     - name: "Test log support"
       run: (cd tracing/test-log-support && cargo test)
@@ -151,9 +155,10 @@ jobs:
     needs: check
     runs-on: ubuntu-latest
     steps:
-    - uses: hecrj/setup-rust-action@v1
+    - uses: actions-rs/toolchain@v1
       with:
-        rust-version: nightly
+        toolchain: nightly
+        profile: minimal
     - uses: actions/checkout@master
     - name: "Test tracing-futures std::future support"
       run: (cd tracing-futures/test_std_future && cargo test)
@@ -169,21 +174,27 @@ jobs:
     needs: check
     runs-on: ubuntu-latest
     steps:
-    - uses: hecrj/setup-rust-action@v1
+    - uses: actions-rs/toolchain@v1
       with:
-        rust-version: stable
+        toolchain: stable
+        components: rustfmt
+        profile: minimal
     - uses: actions/checkout@master
     - name: rustfmt
       run: cargo fmt --all -- --check
 
   warnings:
     # Check for any warnings. This is informational and thus is allowed to fail.
-    needs: check
     runs-on: ubuntu-latest
     steps:
-    - uses: hecrj/setup-rust-action@v1
+    - uses: actions-rs/toolchain@v1
       with:
-        rust-version: stable
+        toolchain: stable
+        components: clippy
+        profile: minimal
     - uses: actions/checkout@master
-    - name: warnings
-      run: RUSTFLAGS="-Dwarnings" cargo check --all
+    - name: Clippy
+      uses: actions-rs/clippy-check@v1
+      with:
+        token: ${{ secrets.GITHUB_TOKEN }}
+        args: --all --bins --examples --tests --benches -- -D warnings

tracing-attributes/src/lib.rs

@@ -95,7 +95,6 @@ use syn::{
 ///     tracing::info!("inside my_function!");
 ///     // ...
 /// }
-/// # fn main() {}
 /// ```
 /// Setting the level for the generated span:
 /// ```
@@ -104,7 +103,6 @@ use syn::{
 /// pub fn my_function() {
 ///     // ...
 /// }
-/// # fn main() {}
 /// ```
 /// Overriding the generated span's target:
 /// ```
@@ -113,7 +111,6 @@ use syn::{
 /// pub fn my_function() {
 ///     // ...
 /// }
-/// # fn main() {}
 /// ```
 ///
 /// To skip recording an argument, pass the argument's name to the `skip`:
@@ -126,7 +123,6 @@ use syn::{
 /// fn my_function(arg: usize, non_debug: NonDebug) {
 ///     // ...
 /// }
-/// # fn main() {}
 /// ```
 ///
 /// If `tracing_futures` is specified as a dependency in `Cargo.toml`,
@@ -139,7 +135,6 @@ use syn::{
 ///     // ...
 ///     # Ok(())
 /// }
-/// # fn main() {}
 /// ```
 ///
 /// [span]: https://docs.rs/tracing/0.1.6/tracing/span/index.html

tracing-attributes/test_async_await/tests/async_fn.rs

@@ -1,5 +1,3 @@
-#![feature(async_await)]
-
 use test_std_future::{
     PollN,
     block_on_future,

tracing-core/src/dispatcher.rs

@@ -38,12 +38,10 @@
 //! #   fn exit(&self, _: &Id) {}
 //! # }
 //! # impl FooSubscriber { fn new() -> Self { FooSubscriber } }
-//! # fn main() {
 //! use dispatcher::Dispatch;
 //!
 //! let my_subscriber = FooSubscriber::new();
 //! let my_dispatch = Dispatch::new(my_subscriber);
-//! # }
 //! ```
 //! Then, we can use [`with_default`] to set our `Dispatch` as the default for
 //! the duration of a block:
@@ -63,7 +61,6 @@
 //! #   fn exit(&self, _: &Id) {}
 //! # }
 //! # impl FooSubscriber { fn new() -> Self { FooSubscriber } }
-//! # fn main() {
 //! # let my_subscriber = FooSubscriber::new();
 //! # let my_dispatch = dispatcher::Dispatch::new(my_subscriber);
 //! // no default subscriber
@@ -74,7 +71,6 @@
 //! });
 //!
 //! // no default subscriber again
-//! # }
 //! ```
 //! It's important to note that `with_default` will not propagate the current
 //! thread's default subscriber to any threads spawned within the `with_default`
@@ -100,7 +96,6 @@
 //! #   fn exit(&self, _: &Id) {}
 //! # }
 //! # impl FooSubscriber { fn new() -> Self { FooSubscriber } }
-//! # fn main() {
 //! # let my_subscriber = FooSubscriber::new();
 //! # let my_dispatch = dispatcher::Dispatch::new(my_subscriber);
 //! // no default subscriber
@@ -111,7 +106,6 @@
 //!     .expect("global default was already set!");
 //!
 //! // `my_subscriber` is now the default
-//! # }
 //! ```
 //!
 //! **Note**: the thread-local scoped dispatcher (`with_default`) requires the
@@ -258,7 +252,7 @@ pub fn set_global_default(dispatcher: Dispatch) -> Result<(), SetGlobalDefaultEr
     if GLOBAL_INIT.compare_and_swap(UNINITIALIZED, INITIALIZING, Ordering::SeqCst) == UNINITIALIZED
     {
         unsafe {
-            GLOBAL_DISPATCH = Some(dispatcher.clone());
+            GLOBAL_DISPATCH = Some(dispatcher);
         }
         GLOBAL_INIT.store(INITIALIZED, Ordering::SeqCst);
         EXISTS.store(true, Ordering::Release);

tracing-core/src/field.rs

@@ -102,7 +102,6 @@ pub struct Iter {
 /// # extern crate tracing_core as tracing;
 /// use std::fmt::{self, Write};
 /// use tracing::field::{Value, Visit, Field};
-/// # fn main() {
 /// pub struct StringVisitor<'a> {
 ///     string: &'a mut String,
 /// }
@@ -112,7 +111,6 @@ pub struct Iter {
 ///         write!(self.string, "{} = {:?}; ", field.name(), value).unwrap();
 ///     }
 /// }
-/// # }
 /// ```
 /// This visitor will format each recorded value using `fmt::Debug`, and
 /// append the field name and formatted value to the provided string,
@@ -135,7 +133,6 @@ pub struct Iter {
 /// # extern crate tracing_core as tracing;
 /// # use std::fmt::{self, Write};
 /// # use tracing::field::{Value, Visit, Field};
-/// # fn main() {
 /// pub struct SumVisitor {
 ///     sum: i64,
 /// }
@@ -153,7 +150,6 @@ pub struct Iter {
 ///         // Do nothing
 ///     }
 /// }
-/// # }
 /// ```
 ///
 /// This visitor (which is probably not particularly useful) keeps a running

tracing-subscriber/src/field/mod.rs

@@ -81,7 +81,6 @@ pub trait VisitOutput<Out>: Visit {
 ///     let mut visitor = MyVisitor::new();
 ///     r.record(&mut visitor);
 /// }
-/// # fn main() {}
 /// ```
 /// [visitor]: https://docs.rs/tracing-core/latest/tracing_core/field/trait.Visit.html
 /// [attr]: https://docs.rs/tracing-core/latest/tracing_core/span/struct.Attributes.html

tracing-subscriber/src/filter/env/mod.rs

@@ -139,10 +139,8 @@ impl EnvFilter {
     /// # Examples
     /// ```rust
     /// use tracing_subscriber::filter::{EnvFilter, LevelFilter};
-    /// # fn main() {
     /// let mut filter = EnvFilter::from_default_env()
     ///     .add_directive(LevelFilter::INFO.into());
-    /// # }
     /// ```
     /// ```rust
     /// use tracing_subscriber::filter::{EnvFilter, Directive};
@@ -153,7 +151,6 @@ impl EnvFilter {
     ///     .add_directive("my_crate::my_other_module::something=info".parse()?);
     /// # Ok(())
     /// # }
-    /// # fn main() {}
     /// ```
     pub fn add_directive(mut self, directive: Directive) -> Self {
         if let Some(stat) = directive.to_static() {

tracing-subscriber/src/layer.rs

@@ -200,7 +200,6 @@ where
     /// ```rust
     /// # use tracing_subscriber::layer::Layer;
     /// # use tracing_core::Subscriber;
-    /// # fn main() {
     /// pub struct FooLayer {
     ///     // ...
     /// }
@@ -243,15 +242,13 @@ where
     /// let subscriber = FooLayer::new()
     ///     .and_then(BarLayer::new())
     ///     .with_subscriber(MySubscriber::new());
-    /// # }
     /// ```
     ///
     /// Multiple layers may be composed in this manner:
     ///
     /// ```rust
     /// # use tracing_subscriber::layer::Layer;
     /// # use tracing_core::Subscriber;
-    /// # fn main() {
     /// # pub struct FooLayer {}
     /// # pub struct BarLayer {}
     /// # pub struct MySubscriber {}
@@ -289,7 +286,6 @@ where
     ///     .and_then(BarLayer::new())
     ///     .and_then(BazLayer::new())
     ///     .with_subscriber(MySubscriber::new());
-    /// # }
     /// ```
     fn and_then<L>(self, layer: L) -> Layered<L, Self, S>
     where
@@ -313,7 +309,6 @@ where
     /// ```rust
     /// # use tracing_subscriber::layer::Layer;
     /// # use tracing_core::Subscriber;
-    /// # fn main() {
     /// pub struct FooLayer {
     ///     // ...
     /// }
@@ -344,7 +339,6 @@ where
     /// # }
     /// let subscriber = FooLayer::new()
     ///     .with_subscriber(MySubscriber::new());
-    /// # }
     ///```
     ///
     /// [`Subscriber`]: https://docs.rs/tracing-core/latest/tracing_core/trait.Subscriber.html

tracing-subscriber/src/registry/mod.rs

@@ -16,7 +16,6 @@
 //! ```rust
 //! use tracing_subscriber::{registry::Registry, Layer};
 //! # use tracing_core::Subscriber;
-//! # fn main() {
 //! # pub struct FooLayer {}
 //! # pub struct BarLayer {}
 //! # impl<S: Subscriber> Layer<S> for FooLayer {}
@@ -31,7 +30,6 @@
 //! let subscriber = FooLayer::new()
 //!     .and_then(BarLayer::new())
 //!     .with_subscriber(Registry::default());
-//! # }
 //! ```
 //!
 //! If a type implementing `Layer` depends on the functionality of a `Registry`
@@ -42,7 +40,6 @@
 //! use tracing_subscriber::{registry, Layer};
 //! use tracing_core::Subscriber;
 //!
-//! # fn main() {
 //! pub struct MyLayer {
 //!     // ...
 //! }
@@ -53,7 +50,6 @@
 //! {
 //!     // ...
 //! }
-//! # }
 //! ```
 //! When this bound is added, the `Layer` implementation will be guaranteed
 //! access to the [`Context`][ctx] methods, such as [`Context::span`][lookup], that