Enable and fix several more clippy lints.

lib/entity/src/lib.rs

@@ -30,9 +30,20 @@
 //!   `Vec`.
 
 #![deny(missing_docs, trivial_numeric_casts, unused_extern_crates)]
+#![warn(unused_import_braces, unstable_features)]
 #![cfg_attr(feature = "clippy", plugin(clippy(conf_file = "../../clippy.toml")))]
 #![cfg_attr(feature = "cargo-clippy",
-            allow(new_without_default, new_without_default_derive, redundant_field_names))]
+            allow(new_without_default, new_without_default_derive))]
+#![cfg_attr(feature="cargo-clippy", warn(
+                float_arithmetic,
+                mut_mut,
+                nonminimal_bool,
+                option_map_unwrap_or,
+                option_map_unwrap_or_else,
+                print_stdout,
+                unicode_not_nfc,
+                use_self,
+                ))]
 
 // Turns on no_std and alloc features if std is not available.
 #![cfg_attr(not(feature = "std"), no_std)]
@@ -91,7 +102,7 @@ macro_rules! entity_impl {
 
         impl $crate::__core::fmt::Display for $entity {
             fn fmt(&self, f: &mut $crate::__core::fmt::Formatter) -> $crate::__core::fmt::Result {
-                write!(f, "{}{}", $display_prefix, self.0)
+                write!(f, concat!($display_prefix, "{}"), self.0)
             }
         }
 

lib/entity/src/map.rs

@@ -49,7 +49,7 @@ where
     pub fn with_default(default: V) -> Self {
         Self {
             elems: Vec::new(),
-            default: default,
+            default,
             unused: PhantomData,
         }
     }

lib/entity/src/packed_option.rs

@@ -28,7 +28,7 @@ impl<T: ReservedValue> PackedOption<T> {
 
     /// Returns `true` if the packed option is a `Some` value.
     pub fn is_some(&self) -> bool {
-        !self.is_none()
+        self.0 != T::reserved_value()
     }
 
     /// Expand the packed option into a normal `Option`.
@@ -62,14 +62,14 @@ impl<T: ReservedValue> PackedOption<T> {
 
 impl<T: ReservedValue> Default for PackedOption<T> {
     /// Create a default packed option representing `None`.
-    fn default() -> PackedOption<T> {
+    fn default() -> Self {
         PackedOption(T::reserved_value())
     }
 }
 
 impl<T: ReservedValue> From<T> for PackedOption<T> {
     /// Convert `t` into a packed `Some(x)`.
-    fn from(t: T) -> PackedOption<T> {
+    fn from(t: T) -> Self {
         debug_assert!(
             t != T::reserved_value(),
             "Can't make a PackedOption from the reserved value."
@@ -80,7 +80,7 @@ impl<T: ReservedValue> From<T> for PackedOption<T> {
 
 impl<T: ReservedValue> From<Option<T>> for PackedOption<T> {
     /// Convert an option into its packed equivalent.
-    fn from(opt: Option<T>) -> PackedOption<T> {
+    fn from(opt: Option<T>) -> Self {
         match opt {
             None => Self::default(),
             Some(t) => t.into(),