[ci] enable clippy (#62)

* [ci] enable clippy

* [clippy] fix clippy issues

Author: gnzlbg

.travis.yml

@@ -21,9 +21,13 @@ matrix:
       script: |
         cargo install rustfmt-nightly
         cargo fmt --all -- --write-mode=diff
+    - env: CLIPPY=On TARGET=x86_64-unknown-linux-gnu NO_ADD=1
+      script: |
+        cargo install clippy
+        cargo clippy --all -- -D clippy-pedantic
   allow_failures:
     - env: RUSTFMT=On TARGET=x86_64-unknown-linux-gnu NO_ADD=1
-
+    - env: CLIPPY=On TARGET=x86_64-unknown-linux-gnu NO_ADD=1
 install:
   - if [ "$NO_ADD" == "" ]; then rustup target add $TARGET; fi
 

examples/nbody.rs

@@ -1,12 +1,20 @@
+//! n-body benchmark from the [benchmarks game][bg].
+//!
+//! [bg]: https://benchmarksgame.alioth.debian.org/u64q/nbody-description.
+//! html#nbody
+
 #![cfg_attr(feature = "strict", deny(warnings))]
 #![feature(cfg_target_feature)]
 #![feature(target_feature)]
+#![cfg_attr(feature = "cargo-clippy",
+            allow(similar_names, missing_docs_in_private_items,
+                  shadow_reuse, print_stdout))]
 
 extern crate stdsimd;
 use self::stdsimd::simd;
 use simd::f64x2;
 
-const PI: f64 = 3.141592653589793;
+const PI: f64 = std::f64::consts::PI;
 const SOLAR_MASS: f64 = 4.0 * PI * PI;
 const DAYS_PER_YEAR: f64 = 365.24;
 
@@ -29,7 +37,7 @@ impl Frsqrt for f64x2 {
                     f32x4::new(t.extract(0), t.extract(1), 0., 0.),
                 ).as_f64x4()
             };
-            f64x2::new(u.extract(0), u.extract(1))
+            Self::new(u.extract(0), u.extract(1))
         }
         #[cfg(all(any(target_arch = "arm", target_arch = "aarch64"),
                   target_feature = "neon"))]
@@ -61,8 +69,8 @@ struct Body {
 impl Body {
     fn new(
         x0: f64, x1: f64, x2: f64, v0: f64, v1: f64, v2: f64, mass: f64
-    ) -> Body {
-        Body {
+    ) -> Self {
+        Self {
             x: [x0, x1, x2],
             _fill: 0.0,
             v: [v0, v1, v2],
@@ -103,8 +111,8 @@ fn advance(bodies: &mut [Body; N_BODIES], dt: f64) {
 
     i = 0;
     while i < N {
-        for m in 0..3 {
-            dx[m] = f64x2::new(r[i][m], r[i + 1][m]);
+        for (m, dx) in dx.iter_mut().enumerate() {
+            *dx = f64x2::new(r[i][m], r[i + 1][m]);
         }
 
         dsquared = dx[0] * dx[0] + dx[1] * dx[1] + dx[2] * dx[2];
@@ -144,11 +152,10 @@ fn energy(bodies: &[Body; N_BODIES]) -> f64 {
         e += bi.mass
             * (bi.v[0] * bi.v[0] + bi.v[1] * bi.v[1] + bi.v[2] * bi.v[2])
             / 2.0;
-        for j in i + 1..N_BODIES {
-            let bj = &bodies[j];
+        for bj in bodies.iter().take(N_BODIES).skip(i + 1) {
             let mut dx = [0.0; 3];
-            for k in 0..3 {
-                dx[k] = bi.x[k] - bj.x[k];
+            for (k, dx) in dx.iter_mut().enumerate() {
+                *dx = bi.x[k] - bj.x[k];
             }
             let mut distance = 0.0;
             for &d in &dx {
@@ -210,7 +217,7 @@ fn main() {
         .nth(1)
         .expect("need one arg")
         .parse()
-        .unwrap();
+        .expect("argument should be a usize");
 
     offset_momentum(&mut bodies);
     println!("{:.9}", energy(&bodies));

examples/play.rs

@@ -1,5 +1,10 @@
 #![cfg_attr(feature = "strict", deny(warnings))]
 #![feature(target_feature)]
+#![cfg_attr(feature = "cargo-clippy",
+            allow(similar_names, missing_docs_in_private_items,
+                  cast_sign_loss, cast_possible_truncation,
+                  cast_possible_wrap, option_unwrap_used, use_debug,
+                  print_stdout))]
 
 #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 mod example {

examples/types.rs

@@ -1,5 +1,8 @@
 #![cfg_attr(feature = "strict", deny(warnings))]
 #![feature(target_feature)]
+#![cfg_attr(feature = "cargo-clippy",
+            allow(missing_docs_in_private_items, result_unwrap_used,
+                  option_unwrap_used, print_stdout, use_debug))]
 
 #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 mod example {

examples/wat.rs

@@ -1,5 +1,8 @@
 #![cfg_attr(feature = "strict", deny(warnings))]
 #![feature(target_feature)]
+#![cfg_attr(feature = "cargo-clippy",
+            allow(missing_docs_in_private_items, result_unwrap_used,
+                  option_unwrap_used, print_stdout, use_debug))]
 
 #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 mod example {

src/lib.rs

@@ -26,7 +26,7 @@
 //! others at:
 //!
 //! * [i686](https://rust-lang-nursery.github.io/stdsimd/i686/stdsimd/)
-//! * [x86_64](https://rust-lang-nursery.github.io/stdsimd/x86_64/stdsimd/)
+//! * [`x86_64`](https://rust-lang-nursery.github.io/stdsimd/x86_64/stdsimd/)
 //! * [arm](https://rust-lang-nursery.github.io/stdsimd/arm/stdsimd/)
 //! * [aarch64](https://rust-lang-nursery.github.io/stdsimd/aarch64/stdsimd/)
 //!
@@ -122,6 +122,12 @@
            simd_ffi, target_feature, cfg_target_feature, i128_type, asm,
            const_atomic_usize_new, stmt_expr_attributes)]
 #![cfg_attr(test, feature(proc_macro, test))]
+#![cfg_attr(feature = "cargo-clippy",
+            allow(inline_always, too_many_arguments, cast_sign_loss,
+                  cast_lossless, cast_possible_wrap,
+                  cast_possible_truncation, cast_precision_loss,
+                  shadow_reuse, cyclomatic_complexity, similar_names,
+                  doc_markdown, many_single_char_names))]
 
 #[cfg(test)]
 extern crate stdsimd_test;

src/macros.rs

@@ -1,3 +1,5 @@
+//! Utility macros
+
 macro_rules! define_ty {
     ($name:ident, $($elty:ident),+) => {
         #[repr(simd)]

src/simd_llvm.rs

@@ -1,3 +1,7 @@
+//! LLVM's simd platform intrinsics
+//!
+//! TODO: should use `link_llvm_intrinsic` instead: issue #112
+
 extern "platform-intrinsic" {
     pub fn simd_eq<T, U>(x: T, y: T) -> U;
     pub fn simd_ne<T, U>(x: T, y: T) -> U;

src/v128.rs

@@ -1,3 +1,5 @@
+//! 128-bit wide vector types
+
 use simd_llvm::*;
 
 define_ty! { f64x2, f64, f64 }

src/v256.rs

@@ -1,3 +1,5 @@
+//! 256-bit wide vector types
+
 use simd_llvm::*;
 
 define_ty! { f64x4, f64, f64, f64, f64 }