From 739007dfb10332ce1606478a86e26774c6cdd356 Mon Sep 17 00:00:00 2001
From: Maxime Augier <max@xolus.net>
Date: Tue, 9 Feb 2021 10:39:39 +0100
Subject: [PATCH 1/2] Derive PartialEq and Eq for multiarray

---
 src/lib.rs | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index 73069b9..a514dbb 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -40,7 +40,7 @@ use std::ops::{ Index, IndexMut };
 
 /// Helper type to wrap things. This helps avoiding trait coherency issues
 /// w.r.t. `AsRef` and `From`.
-#[derive(Copy,Clone)]
+#[derive(Copy,Clone,PartialEq,Eq)]
 pub struct Wrapped<T>(pub T);
 
 impl<T> From<T> for Wrapped<[T; 1]> {
@@ -65,10 +65,10 @@ impl<B: ?Sized, O: AsMut<B>> AsMut<B> for Wrapped<O> {
 /// memory layout of a multi-dimensional array.
 pub unsafe trait LayoutHelper {
     /// type for a small fixed-size array of isize
-    type I: AsRef<[isize]> + AsMut<[isize]> + Copy + Clone;
+    type I: AsRef<[isize]> + AsMut<[isize]> + Copy + Clone + PartialEq + Eq;
 
     /// type for a small fixed-size array of usize
-    type U: AsRef<[usize]> + AsMut<[usize]> + Copy + Clone;
+    type U: AsRef<[usize]> + AsMut<[usize]> + Copy + Clone + PartialEq + Eq;
 
     /// length of the fixed-size arrays this type can create
     fn dimensions() -> usize;
@@ -114,6 +114,7 @@ declare_int_array_maker! { Dim4, 4, [0,0,0,0], Dim3 }
 declare_int_array_maker! { Dim5, 5, [0,0,0,0,0], Dim4 }
 declare_int_array_maker! { Dim6, 6, [0,0,0,0,0,0], Dim5 }
 
+#[derive(PartialEq, Eq)]
 struct MultiArrayLayout<A> where A: LayoutHelper {
     extents: A::U,
     steps: A::I,
@@ -300,6 +301,7 @@ pub struct MultiArrayRefMut<'a, T: 'a, A> where A: LayoutHelper {
 /// matrix[[1,0]] = 3; matrix[[1,1]] = 4;
 /// matrix[[2,0]] = 5; matrix[[2,1]] = 6;
 /// ```
+#[derive(PartialEq,Eq)]
 pub struct MultiArray<T, A> where A: LayoutHelper {
     layout: MultiArrayLayout<A>,
     data: Box<[T]>,

From a661bb77049811f62dcab2382094e837ed9c6c1c Mon Sep 17 00:00:00 2001
From: Maxime Augier <max@xolus.net>
Date: Tue, 9 Feb 2021 11:06:56 +0100
Subject: [PATCH 2/2] Welp, work around autoderive shortcomings

---
 src/lib.rs | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index a514dbb..e4d6804 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -114,7 +114,7 @@ declare_int_array_maker! { Dim4, 4, [0,0,0,0], Dim3 }
 declare_int_array_maker! { Dim5, 5, [0,0,0,0,0], Dim4 }
 declare_int_array_maker! { Dim6, 6, [0,0,0,0,0,0], Dim5 }
 
-#[derive(PartialEq, Eq)]
+#[derive(Eq)]
 struct MultiArrayLayout<A> where A: LayoutHelper {
     extents: A::U,
     steps: A::I,
@@ -128,6 +128,12 @@ impl<A> Clone for MultiArrayLayout<A> where A: LayoutHelper {
     }
 }
 
+impl<A> PartialEq for MultiArrayLayout<A> where A: LayoutHelper {
+    fn eq(&self, other: &Self) -> bool {
+        self.extents.eq(&other.extents) && self.steps.eq(&other.steps)
+    }
+}
+
 fn c_array_layout(extents: &[usize], steps: &mut [isize]) -> usize {
     let dim = extents.len();
     assert!(dim == steps.len());
@@ -301,12 +307,18 @@ pub struct MultiArrayRefMut<'a, T: 'a, A> where A: LayoutHelper {
 /// matrix[[1,0]] = 3; matrix[[1,1]] = 4;
 /// matrix[[2,0]] = 5; matrix[[2,1]] = 6;
 /// ```
-#[derive(PartialEq,Eq)]
+#[derive(Eq)]
 pub struct MultiArray<T, A> where A: LayoutHelper {
     layout: MultiArrayLayout<A>,
     data: Box<[T]>,
 }
 
+impl <T, A> PartialEq for MultiArray<T, A> where T: PartialEq, A: LayoutHelper {
+    fn eq(&self, other: &Self) -> bool {
+        self.layout.eq(&other.layout) && self.data.eq(&other.data)
+    }
+}
+
 /// Shared view of a 1D array
 pub type Array1DRef<'a, T> = MultiArrayRef<'a, T, Dim1>;
 /// Shared view of a 2D array