Auto merge of #295 - nical:clippy, r=kvark

Address some clippy lints.

I'd like to be able to run clippy every now and then but right now there is too much noise for me to notice anything. This removes most of the warnings down to a more manageable level.

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src/point.rs

@@ -68,8 +68,8 @@ impl<T, U> TypedPoint2D<T, U> {
     #[inline]
     pub fn new(x: T, y: T) -> Self {
         TypedPoint2D {
-            x: x,
-            y: y,
+            x,
+            y,
             _unit: PhantomData,
         }
     }
@@ -455,9 +455,9 @@ impl<T: Copy, U> TypedPoint3D<T, U> {
     #[inline]
     pub fn new(x: T, y: T, z: T) -> Self {
         TypedPoint3D {
-            x: x,
-            y: y,
-            z: z,
+            x,
+            y,
+            z,
             _unit: PhantomData,
         }
     }

src/rect.rs

@@ -97,8 +97,8 @@ impl<T, U> TypedRect<T, U> {
     /// Constructor.
     pub fn new(origin: TypedPoint2D<T, U>, size: TypedSize2D<T, U>) -> Self {
         TypedRect {
-            origin: origin,
-            size: size,
+            origin,
+            size,
         }
     }
 }

src/side_offsets.rs

@@ -45,10 +45,10 @@ impl<T: Copy, U> TypedSideOffsets2D<T, U> {
     /// Constructor taking a scalar for each side.
     pub fn new(top: T, right: T, bottom: T, left: T) -> Self {
         TypedSideOffsets2D {
-            top: top,
-            right: right,
-            bottom: bottom,
-            left: left,
+            top,
+            right,
+            bottom,
+            left,
             _unit: PhantomData,
         }
     }

src/size.rs

@@ -47,8 +47,8 @@ impl<T, U> TypedSize2D<T, U> {
     /// Constructor taking scalar values.
     pub fn new(width: T, height: T) -> Self {
         TypedSize2D {
-            width: width,
-            height: height,
+            width,
+            height,
             _unit: PhantomData,
         }
     }

src/transform2d.rs

@@ -7,6 +7,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![cfg_attr(feature = "cargo-clippy", allow(just_underscores_and_digits))]
+
 use super::{UnknownUnit, Angle};
 use num::{One, Zero};
 use point::TypedPoint2D;
@@ -46,19 +48,19 @@ impl<T: Copy, Src, Dst> TypedTransform2D<T, Src, Dst> {
     /// Create a transform specifying its matrix elements in row-major order.
     pub fn row_major(m11: T, m12: T, m21: T, m22: T, m31: T, m32: T) -> Self {
         TypedTransform2D {
-            m11: m11, m12: m12,
-            m21: m21, m22: m22,
-            m31: m31, m32: m32,
+            m11, m12,
+            m21, m22,
+            m31, m32,
             _unit: PhantomData,
         }
     }
 
     /// Create a transform specifying its matrix elements in column-major order.
     pub fn column_major(m11: T, m21: T, m31: T, m12: T, m22: T, m32: T) -> Self {
         TypedTransform2D {
-            m11: m11, m12: m12,
-            m21: m21, m22: m22,
-            m31: m31, m32: m32,
+            m11, m12,
+            m21, m22,
+            m31, m32,
             _unit: PhantomData,
         }
     }

src/transform3d.rs

@@ -7,6 +7,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![cfg_attr(feature = "cargo-clippy", allow(just_underscores_and_digits))]
+
 use super::{UnknownUnit, Angle};
 use approxeq::ApproxEq;
 use homogen::HomogeneousVector;
@@ -51,17 +53,18 @@ impl<T, Src, Dst> TypedTransform3D<T, Src, Dst> {
     /// For example, the translation terms m41, m42, m43 on the last row with the
     /// row-major convention) are the 13rd, 14th and 15th parameters.
     #[inline]
+    #[cfg_attr(feature = "cargo-clippy", allow(too_many_arguments))]
     pub fn row_major(
             m11: T, m12: T, m13: T, m14: T,
             m21: T, m22: T, m23: T, m24: T,
             m31: T, m32: T, m33: T, m34: T,
             m41: T, m42: T, m43: T, m44: T)
          -> Self {
         TypedTransform3D {
-            m11: m11, m12: m12, m13: m13, m14: m14,
-            m21: m21, m22: m22, m23: m23, m24: m24,
-            m31: m31, m32: m32, m33: m33, m34: m34,
-            m41: m41, m42: m42, m43: m43, m44: m44,
+            m11, m12, m13, m14,
+            m21, m22, m23, m24,
+            m31, m32, m33, m34,
+            m41, m42, m43, m44,
             _unit: PhantomData,
         }
     }
@@ -71,17 +74,18 @@ impl<T, Src, Dst> TypedTransform3D<T, Src, Dst> {
     /// For example, the translation terms m41, m42, m43 on the last column with the
     /// column-major convention) are the 4th, 8th and 12nd parameters.
     #[inline]
+    #[cfg_attr(feature = "cargo-clippy", allow(too_many_arguments))]
     pub fn column_major(
             m11: T, m21: T, m31: T, m41: T,
             m12: T, m22: T, m32: T, m42: T,
             m13: T, m23: T, m33: T, m43: T,
             m14: T, m24: T, m34: T, m44: T)
          -> Self {
         TypedTransform3D {
-            m11: m11, m12: m12, m13: m13, m14: m14,
-            m21: m21, m22: m22, m23: m23, m24: m24,
-            m31: m31, m32: m32, m33: m33, m34: m34,
-            m41: m41, m42: m42, m43: m43, m44: m44,
+            m11, m12, m13, m14,
+            m21, m22, m23, m24,
+            m31, m32, m33, m34,
+            m41, m42, m43, m44,
             _unit: PhantomData,
         }
     }

src/trig.rs

@@ -32,13 +32,17 @@ macro_rules! trig {
             /// Note that it does not deal with the case where both x and y are 0.
             #[inline]
             fn fast_atan2(y: $ty, x: $ty) -> $ty {
+                // This macro is used with f32 and f64 and clippy warns about the extra
+                // precision with f32.
+                #![cfg_attr(feature = "cargo-clippy", allow(excessive_precision))]
+
                 // See https://math.stackexchange.com/questions/1098487/atan2-faster-approximation#1105038
                 use core::$ty::consts;
                 let x_abs = x.abs();
                 let y_abs = y.abs();
                 let a = x_abs.min(y_abs) / x_abs.max(y_abs);
                 let s = a * a;
-                let mut result = ((-0.0464964749 * s + 0.15931422) * s - 0.327622764) * s * a + a;
+                let mut result = ((-0.046_496_474_9 * s + 0.159_314_22) * s - 0.327_622_764) * s * a + a;
                 if y_abs > x_abs {
                     result = consts::FRAC_PI_2 - result;
                 }

src/vector.rs

@@ -65,8 +65,8 @@ impl<T, U> TypedVector2D<T, U> {
     #[inline]
     pub fn new(x: T, y: T) -> Self {
         TypedVector2D {
-            x: x,
-            y: y,
+            x,
+            y,
             _unit: PhantomData,
         }
     }
@@ -479,9 +479,9 @@ impl<T, U> TypedVector3D<T, U> {
     #[inline]
     pub fn new(x: T, y: T, z: T) -> Self {
         TypedVector3D {
-            x: x,
-            y: y,
-            z: z,
+            x,
+            y,
+            z,
             _unit: PhantomData,
         }
     }