Merge pull request #11 from bryceberger/all-to-slice

Change `all()` method to return `&'static []`

Author: greyblake

kinded/src/traits.rs

@@ -10,6 +10,6 @@ pub trait Kinded {
 }
 
 pub trait Kind: PartialEq + Eq + Debug + Clone + Copy {
-    /// Return a vector with all possible kind variants.
-    fn all() -> Vec<Self>;
+    /// Return a slice with all possible kind variants.
+    fn all() -> &'static [Self];
 }

kinded_macros/src/gen/kind_enum.rs

@@ -31,8 +31,8 @@ fn gen_definition(meta: &Meta) -> TokenStream {
         }                                                                      // }
 
         impl #kind_name {                                                      // impl DrinkKind {
-            pub fn all() -> Vec<#kind_name> {                                  //     pub fn all() -> Vec<DrinkKind> {
-                vec![                                                          //         vec![
+            pub fn all() -> &'static [#kind_name] {                            //     pub fn all() -> &'static [DrinkKind] {
+                &[                                                             //         &[
                     #(#kind_name::#variant_names),*                            //             DrinkKind::Mate, DrinkKind::Coffee, DrinkKind::Tea
                 ]                                                              //         ]
             }                                                                  //     }
@@ -139,7 +139,7 @@ fn gen_impl_kind_trait(meta: &Meta) -> TokenStream {
 
     quote!(
         impl ::kinded::Kind for #kind_name {
-            fn all() -> Vec<#kind_name> {
+            fn all() -> &'static [#kind_name] {
                 Self::all()
             }
         }

test_suite/src/lib.rs

@@ -275,27 +275,20 @@ mod kind_enum {
         mod kind_trait {
             use crate::RoleKind;
 
-            fn get_all_kinds<T: kinded::Kind>() -> Vec<T> {
-                T::all()
-            }
-
             #[test]
             fn should_implement_kind_trait() {
-                let kinds = get_all_kinds::<RoleKind>();
                 assert_eq!(
-                    kinds,
-                    vec![RoleKind::Guest, RoleKind::User, RoleKind::Admin]
+                    RoleKind::all(),
+                    [RoleKind::Guest, RoleKind::User, RoleKind::Admin]
                 )
             }
         }
     }
 
     #[test]
     fn should_provide_all_function_that_returns_iterator() {
-        assert_eq!(
-            RoleKind::all(),
-            vec![RoleKind::Guest, RoleKind::User, RoleKind::Admin],
-        )
+        fn impl_iter(_: impl IntoIterator<Item = &'static RoleKind>) {}
+        impl_iter(RoleKind::all());
     }
 }