From e7344d03b467e87b3e50fa8d7ecd74994b46a4e6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?H=C3=A9ctor=20Ram=C3=B3n=20Jim=C3=A9nez?=
 <hector0193@gmail.com>
Date: Thu, 7 Jan 2021 21:07:44 +0100
Subject: [PATCH] Use `BTreeMap` for splits and regions in `pane_grid`

This preserves ordering between calls to update and draw logic.
---
 native/src/widget/pane_grid/node.rs  | 14 +++++++-------
 native/src/widget/pane_grid/pane.rs  |  2 +-
 native/src/widget/pane_grid/split.rs |  2 +-
 native/src/widget/pane_grid/state.rs |  6 +++---
 4 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/native/src/widget/pane_grid/node.rs b/native/src/widget/pane_grid/node.rs
index 319936fc..84714e00 100644
--- a/native/src/widget/pane_grid/node.rs
+++ b/native/src/widget/pane_grid/node.rs
@@ -3,7 +3,7 @@ use crate::{
     Rectangle, Size,
 };
 
-use std::collections::HashMap;
+use std::collections::BTreeMap;
 
 /// A layout node of a [`PaneGrid`].
 ///
@@ -59,8 +59,8 @@ impl Node {
         &self,
         spacing: f32,
         size: Size,
-    ) -> HashMap<Pane, Rectangle> {
-        let mut regions = HashMap::new();
+    ) -> BTreeMap<Pane, Rectangle> {
+        let mut regions = BTreeMap::new();
 
         self.compute_regions(
             spacing,
@@ -83,8 +83,8 @@ impl Node {
         &self,
         spacing: f32,
         size: Size,
-    ) -> HashMap<Split, (Axis, Rectangle, f32)> {
-        let mut splits = HashMap::new();
+    ) -> BTreeMap<Split, (Axis, Rectangle, f32)> {
+        let mut splits = BTreeMap::new();
 
         self.compute_splits(
             spacing,
@@ -191,7 +191,7 @@ impl Node {
         &self,
         spacing: f32,
         current: &Rectangle,
-        regions: &mut HashMap<Pane, Rectangle>,
+        regions: &mut BTreeMap<Pane, Rectangle>,
     ) {
         match self {
             Node::Split {
@@ -212,7 +212,7 @@ impl Node {
         &self,
         spacing: f32,
         current: &Rectangle,
-        splits: &mut HashMap<Split, (Axis, Rectangle, f32)>,
+        splits: &mut BTreeMap<Split, (Axis, Rectangle, f32)>,
     ) {
         match self {
             Node::Split {
diff --git a/native/src/widget/pane_grid/pane.rs b/native/src/widget/pane_grid/pane.rs
index 39d9f3ef..d6fbab83 100644
--- a/native/src/widget/pane_grid/pane.rs
+++ b/native/src/widget/pane_grid/pane.rs
@@ -1,5 +1,5 @@
 /// A rectangular region in a [`PaneGrid`] used to display widgets.
 ///
 /// [`PaneGrid`]: crate::widget::PaneGrid
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Pane(pub(super) usize);
diff --git a/native/src/widget/pane_grid/split.rs b/native/src/widget/pane_grid/split.rs
index 16975abc..8132272a 100644
--- a/native/src/widget/pane_grid/split.rs
+++ b/native/src/widget/pane_grid/split.rs
@@ -1,5 +1,5 @@
 /// A divider that splits a region in a [`PaneGrid`] into two different panes.
 ///
 /// [`PaneGrid`]: crate::widget::PaneGrid
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Split(pub(super) usize);
diff --git a/native/src/widget/pane_grid/state.rs b/native/src/widget/pane_grid/state.rs
index 666e1ca0..fb96f89f 100644
--- a/native/src/widget/pane_grid/state.rs
+++ b/native/src/widget/pane_grid/state.rs
@@ -3,7 +3,7 @@ use crate::{
     Hasher, Point, Rectangle, Size,
 };
 
-use std::collections::HashMap;
+use std::collections::{BTreeMap, HashMap};
 
 /// The state of a [`PaneGrid`].
 ///
@@ -257,7 +257,7 @@ impl Internal {
         &self,
         spacing: f32,
         size: Size,
-    ) -> HashMap<Pane, Rectangle> {
+    ) -> BTreeMap<Pane, Rectangle> {
         self.layout.pane_regions(spacing, size)
     }
 
@@ -265,7 +265,7 @@ impl Internal {
         &self,
         spacing: f32,
         size: Size,
-    ) -> HashMap<Split, (Axis, Rectangle, f32)> {
+    ) -> BTreeMap<Split, (Axis, Rectangle, f32)> {
         self.layout.split_regions(spacing, size)
     }