wip: generic over reference type for rng

Author: zeon256

src/lib.rs

@@ -70,7 +70,6 @@ pub mod quickfind;
 pub mod quickunion;
 pub mod rng;
 
-use core::borrow::{Borrow, BorrowMut};
 use core::marker::PhantomData;
 use core::ops::AddAssign;
 
@@ -86,7 +85,11 @@ pub struct Fat;
 pub struct Thin;
 
 pub struct Owned;
-pub struct Borrowed<T = Fat>(PhantomData<T>);
+pub struct Borrowed<P: PointerType + ?Sized = Fat>(PhantomData<P>);
+
+pub trait PointerType {}
+impl PointerType for Fat {}
+impl PointerType for Thin {}
 
 /// Any type that can be used to index internal buffer
 pub trait VertexType: Eq + Copy {

src/quickunion/constructors.rs

@@ -1,9 +1,10 @@
 //! Constructors and macros for QuickUnion
 
-use rand_core::RngCore;
 use crate::{
-    quickunion::heuristics::ByRandom, rng::PhantomRng, ByRank, BySize, QuickUnion, UnionFind, Unweighted, Owned
+    quickunion::heuristics::ByRandom, rng::PhantomRng, ByRank, BySize, Owned, QuickUnion,
+    UnionFind, Unweighted,
 };
+use rand_core::RngCore;
 
 /// Helper macro to generate the representative array
 macro_rules! generate_representative {

src/quickunion/mod.rs

@@ -53,7 +53,7 @@ mod by_random_tests {
         use rand_core::SeedableRng;
         use rand_hc::Hc128Rng;
 
-        use crate::{Borrowed, Fat, Owned, QuickUnion, Thin, UnionFind, quickunion::ByRandom};
+        use crate::{quickunion::ByRandom, Borrowed, Fat, Owned, QuickUnion, Thin, UnionFind};
 
         #[test]
         fn test_one_union() {
@@ -70,19 +70,49 @@ mod by_random_tests {
         fn test_size() {
             const N: usize = 128;
             assert_eq!(
-                mem::size_of::<UnionFind::<'_, QuickUnion<ByRandom<Hc128Rng, Owned>, false>, u8, N>>(),
+                mem::size_of::<UnionFind::<'_, QuickUnion<ByRandom<Hc128Rng, Owned>, false>, u8, N>>(
+                ),
                 mem::size_of::<[u8; N]>()
                     + mem::size_of::<[usize; 0]>()
                     + mem::size_of::<Hc128Rng>()
             );
         }
 
+        #[test]
+        fn test_size_borrowed_rng() {
+            const N: usize = 128;
+            assert_eq!(
+                mem::size_of::<
+                    UnionFind::<'_, QuickUnion<ByRandom<&mut Hc128Rng, Owned>, false>, u8, N>,
+                >(),
+                mem::size_of::<[u8; N]>()
+                    + mem::size_of::<[usize; 0]>()
+                    + mem::size_of::<&Hc128Rng>()
+            );
+        }
+
+        #[test]
+        fn borrowed_rng_ctor() {
+            const N: usize = 10;
+            let mut rng = Hc128Rng::seed_from_u64(67);
+
+            let mut uf =
+                UnionFind::<'_, QuickUnion<ByRandom<&mut Hc128Rng, Owned>, false>, u8, N>::new(
+                    &mut rng,
+                );
+
+            uf.union_sets(0, 1);
+
+            assert!(uf.connected(0, 1));
+        }
+
         #[test]
         fn test_size_padded() {
             const M: usize = 100;
 
             assert_eq!(
-                mem::size_of::<UnionFind::<'_, QuickUnion<ByRandom<Hc128Rng, Owned>, false>, u8, M>>(),
+                mem::size_of::<UnionFind::<'_, QuickUnion<ByRandom<Hc128Rng, Owned>, false>, u8, M>>(
+                ),
                 mem::size_of::<[u8; M]>()
                     + mem::size_of::<[usize; 0]>()
                     + mem::size_of::<Hc128Rng>()
@@ -94,7 +124,9 @@ mod by_random_tests {
         fn test_size_borrowed_thin() {
             const N: usize = 128;
             assert_eq!(
-                mem::size_of::<UnionFind::<'_, QuickUnion<ByRandom<Hc128Rng, Borrowed<Thin>>, false>, u8, N>>(),
+                mem::size_of::<
+                    UnionFind::<'_, QuickUnion<ByRandom<Hc128Rng, Borrowed<Thin>>, false>, u8, N>,
+                >(),
                 mem::size_of::<&[u8; N]>() + mem::size_of::<Hc128Rng>()
             );
         }
@@ -103,7 +135,9 @@ mod by_random_tests {
         fn test_size_borrowed_fat() {
             const N: usize = 128;
             assert_eq!(
-                mem::size_of::<UnionFind::<'_, QuickUnion<ByRandom<Hc128Rng, Borrowed<Fat>>, false>, u8, N>>(),
+                mem::size_of::<
+                    UnionFind::<'_, QuickUnion<ByRandom<Hc128Rng, Borrowed<Fat>>, false>, u8, N>,
+                >(),
                 mem::size_of::<&[u8]>() + mem::size_of::<Hc128Rng>()
             );
         }

src/rng.rs

@@ -28,4 +28,4 @@ impl RngCore for PhantomRng {
     fn fill_bytes(&mut self, _dst: &mut [u8]) {
         unreachable!("Should not be called!")
     }
-}
+}