From 71c0e6891565f84832e429c96ef06d93cf99b3ad Mon Sep 17 00:00:00 2001
From: "Darrin W. Cullop" <Darrin.Cullop@microsoft.com>
Date: Fri, 15 Dec 2023 20:00:52 -0800
Subject: [PATCH] housekeeping: Merged Sealing of List Internals (#796)

Co-authored-by: Chris Pulman <chris.pulman@yahoo.com>
---
 src/DynamicData/List/Internal/AutoRefresh.cs           | 2 +-
 src/DynamicData/List/Internal/ChangeSetMergeTracker.cs | 2 +-
 src/DynamicData/List/Internal/DeferUntilLoaded.cs      | 2 +-
 src/DynamicData/List/Internal/EditDiff.cs              | 2 +-
 src/DynamicData/List/Internal/Filter.cs                | 2 +-
 src/DynamicData/List/Internal/FilterOnObservable.cs    | 2 +-
 src/DynamicData/List/Internal/FilterOnProperty.cs      | 2 +-
 src/DynamicData/List/Internal/FilterStatic.cs          | 2 +-
 src/DynamicData/List/Internal/Group.cs                 | 2 +-
 src/DynamicData/List/Internal/Pager.cs                 | 2 +-
 src/DynamicData/List/Internal/QueryWhenChanged.cs      | 2 +-
 src/DynamicData/List/Internal/RefCount.cs              | 2 +-
 src/DynamicData/List/Internal/ReferenceCountTracker.cs | 2 +-
 src/DynamicData/List/Internal/ToObservableChangeSet.cs | 2 +-
 src/DynamicData/List/Internal/TransformAsync.cs        | 2 +-
 15 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/src/DynamicData/List/Internal/AutoRefresh.cs b/src/DynamicData/List/Internal/AutoRefresh.cs
index 0ceb73783..7b6d0f7fc 100644
--- a/src/DynamicData/List/Internal/AutoRefresh.cs
+++ b/src/DynamicData/List/Internal/AutoRefresh.cs
@@ -10,7 +10,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class AutoRefresh<TObject, TAny>(IObservable<IChangeSet<TObject>> source, Func<TObject, IObservable<TAny>> reEvaluator, TimeSpan? buffer = null, IScheduler? scheduler = null)
+internal sealed class AutoRefresh<TObject, TAny>(IObservable<IChangeSet<TObject>> source, Func<TObject, IObservable<TAny>> reEvaluator, TimeSpan? buffer = null, IScheduler? scheduler = null)
     where TObject : notnull
 {
     private readonly Func<TObject, IObservable<TAny>> _reEvaluator = reEvaluator ?? throw new ArgumentNullException(nameof(reEvaluator));
diff --git a/src/DynamicData/List/Internal/ChangeSetMergeTracker.cs b/src/DynamicData/List/Internal/ChangeSetMergeTracker.cs
index 465837582..b518116be 100644
--- a/src/DynamicData/List/Internal/ChangeSetMergeTracker.cs
+++ b/src/DynamicData/List/Internal/ChangeSetMergeTracker.cs
@@ -4,7 +4,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class ChangeSetMergeTracker<TObject>
+internal sealed class ChangeSetMergeTracker<TObject>
     where TObject : notnull
 {
     private readonly ChangeAwareList<TObject> _resultList = new();
diff --git a/src/DynamicData/List/Internal/DeferUntilLoaded.cs b/src/DynamicData/List/Internal/DeferUntilLoaded.cs
index ae70ffae8..115fd8e88 100644
--- a/src/DynamicData/List/Internal/DeferUntilLoaded.cs
+++ b/src/DynamicData/List/Internal/DeferUntilLoaded.cs
@@ -8,7 +8,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class DeferUntilLoaded<T>(IObservable<IChangeSet<T>> source)
+internal sealed class DeferUntilLoaded<T>(IObservable<IChangeSet<T>> source)
     where T : notnull
 {
     private readonly IObservable<IChangeSet<T>> _source = source ?? throw new ArgumentNullException(nameof(source));
diff --git a/src/DynamicData/List/Internal/EditDiff.cs b/src/DynamicData/List/Internal/EditDiff.cs
index d5c645fb2..97af3b848 100644
--- a/src/DynamicData/List/Internal/EditDiff.cs
+++ b/src/DynamicData/List/Internal/EditDiff.cs
@@ -6,7 +6,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class EditDiff<T>(ISourceList<T> source, IEqualityComparer<T>? equalityComparer)
+internal sealed class EditDiff<T>(ISourceList<T> source, IEqualityComparer<T>? equalityComparer)
     where T : notnull
 {
     private readonly IEqualityComparer<T> _equalityComparer = equalityComparer ?? EqualityComparer<T>.Default;
diff --git a/src/DynamicData/List/Internal/Filter.cs b/src/DynamicData/List/Internal/Filter.cs
index c69db656a..79df2e89d 100644
--- a/src/DynamicData/List/Internal/Filter.cs
+++ b/src/DynamicData/List/Internal/Filter.cs
@@ -8,7 +8,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class Filter<T>
+internal sealed class Filter<T>
     where T : notnull
 {
     private readonly ListFilterPolicy _policy;
diff --git a/src/DynamicData/List/Internal/FilterOnObservable.cs b/src/DynamicData/List/Internal/FilterOnObservable.cs
index fab810937..3ee229a38 100644
--- a/src/DynamicData/List/Internal/FilterOnObservable.cs
+++ b/src/DynamicData/List/Internal/FilterOnObservable.cs
@@ -8,7 +8,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class FilterOnObservable<TObject>(IObservable<IChangeSet<TObject>> source, Func<TObject, IObservable<bool>> filter, TimeSpan? buffer = null, IScheduler? scheduler = null)
+internal sealed class FilterOnObservable<TObject>(IObservable<IChangeSet<TObject>> source, Func<TObject, IObservable<bool>> filter, TimeSpan? buffer = null, IScheduler? scheduler = null)
     where TObject : notnull
 {
     private readonly Func<TObject, IObservable<bool>> _filter = filter ?? throw new ArgumentNullException(nameof(filter));
diff --git a/src/DynamicData/List/Internal/FilterOnProperty.cs b/src/DynamicData/List/Internal/FilterOnProperty.cs
index ccd17ddb0..a2b7f9112 100644
--- a/src/DynamicData/List/Internal/FilterOnProperty.cs
+++ b/src/DynamicData/List/Internal/FilterOnProperty.cs
@@ -9,7 +9,7 @@
 namespace DynamicData.List.Internal;
 
 [Obsolete("Use AutoRefresh(), followed by Filter() instead")]
-internal class FilterOnProperty<TObject, TProperty>(IObservable<IChangeSet<TObject>> source, Expression<Func<TObject, TProperty>> propertySelector, Func<TObject, bool> predicate, TimeSpan? throttle = null, IScheduler? scheduler = null)
+internal sealed class FilterOnProperty<TObject, TProperty>(IObservable<IChangeSet<TObject>> source, Expression<Func<TObject, TProperty>> propertySelector, Func<TObject, bool> predicate, TimeSpan? throttle = null, IScheduler? scheduler = null)
     where TObject : INotifyPropertyChanged
 {
     public IObservable<IChangeSet<TObject>> Run() => source.AutoRefresh(propertySelector, propertyChangeThrottle: throttle, scheduler: scheduler).Filter(predicate);
diff --git a/src/DynamicData/List/Internal/FilterStatic.cs b/src/DynamicData/List/Internal/FilterStatic.cs
index 83ac36e4b..be99eaff9 100644
--- a/src/DynamicData/List/Internal/FilterStatic.cs
+++ b/src/DynamicData/List/Internal/FilterStatic.cs
@@ -6,7 +6,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class FilterStatic<T>(IObservable<IChangeSet<T>> source, Func<T, bool> predicate)
+internal sealed class FilterStatic<T>(IObservable<IChangeSet<T>> source, Func<T, bool> predicate)
     where T : notnull
 {
     private readonly Func<T, bool> _predicate = predicate ?? throw new ArgumentNullException(nameof(predicate));
diff --git a/src/DynamicData/List/Internal/Group.cs b/src/DynamicData/List/Internal/Group.cs
index 4586c344a..dfe64957a 100644
--- a/src/DynamicData/List/Internal/Group.cs
+++ b/src/DynamicData/List/Internal/Group.cs
@@ -4,7 +4,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class Group<TObject, TGroup>(TGroup groupKey) : IGroup<TObject, TGroup>, IDisposable, IEquatable<Group<TObject, TGroup>>
+internal sealed class Group<TObject, TGroup>(TGroup groupKey) : IGroup<TObject, TGroup>, IDisposable, IEquatable<Group<TObject, TGroup>>
     where TObject : notnull
 {
     public TGroup GroupKey { get; } = groupKey;
diff --git a/src/DynamicData/List/Internal/Pager.cs b/src/DynamicData/List/Internal/Pager.cs
index 723d1cb83..6a53a4bb1 100644
--- a/src/DynamicData/List/Internal/Pager.cs
+++ b/src/DynamicData/List/Internal/Pager.cs
@@ -7,7 +7,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class Pager<T>(IObservable<IChangeSet<T>> source, IObservable<IPageRequest> requests)
+internal sealed class Pager<T>(IObservable<IChangeSet<T>> source, IObservable<IPageRequest> requests)
     where T : notnull
 {
     private readonly IObservable<IPageRequest> _requests = requests ?? throw new ArgumentNullException(nameof(requests));
diff --git a/src/DynamicData/List/Internal/QueryWhenChanged.cs b/src/DynamicData/List/Internal/QueryWhenChanged.cs
index 71f169874..54ac665f6 100644
--- a/src/DynamicData/List/Internal/QueryWhenChanged.cs
+++ b/src/DynamicData/List/Internal/QueryWhenChanged.cs
@@ -8,7 +8,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class QueryWhenChanged<T>(IObservable<IChangeSet<T>> source)
+internal sealed class QueryWhenChanged<T>(IObservable<IChangeSet<T>> source)
     where T : notnull
 {
     private readonly IObservable<IChangeSet<T>> _source = source ?? throw new ArgumentNullException(nameof(source));
diff --git a/src/DynamicData/List/Internal/RefCount.cs b/src/DynamicData/List/Internal/RefCount.cs
index 329064207..ee9f75d47 100644
--- a/src/DynamicData/List/Internal/RefCount.cs
+++ b/src/DynamicData/List/Internal/RefCount.cs
@@ -7,7 +7,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class RefCount<T>(IObservable<IChangeSet<T>> source)
+internal sealed class RefCount<T>(IObservable<IChangeSet<T>> source)
     where T : notnull
 {
     private readonly object _locker = new();
diff --git a/src/DynamicData/List/Internal/ReferenceCountTracker.cs b/src/DynamicData/List/Internal/ReferenceCountTracker.cs
index b9fed75f2..bb3e92dc7 100644
--- a/src/DynamicData/List/Internal/ReferenceCountTracker.cs
+++ b/src/DynamicData/List/Internal/ReferenceCountTracker.cs
@@ -9,7 +9,7 @@ namespace DynamicData.List.Internal;
 /// <para>Thanks dudes.</para>
 /// </summary>
 /// <typeparam name="T">The type of the item.</typeparam>
-internal class ReferenceCountTracker<T>
+internal sealed class ReferenceCountTracker<T>
     where T : notnull
 {
     public IEnumerable<T> Items => ReferenceCounts.Keys;
diff --git a/src/DynamicData/List/Internal/ToObservableChangeSet.cs b/src/DynamicData/List/Internal/ToObservableChangeSet.cs
index 8ef2ff14f..6f8c9152f 100644
--- a/src/DynamicData/List/Internal/ToObservableChangeSet.cs
+++ b/src/DynamicData/List/Internal/ToObservableChangeSet.cs
@@ -9,7 +9,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class ToObservableChangeSet<TObject>
+internal sealed class ToObservableChangeSet<TObject>
     where TObject : notnull
 {
     private readonly Func<TObject, TimeSpan?>? _expireAfter;
diff --git a/src/DynamicData/List/Internal/TransformAsync.cs b/src/DynamicData/List/Internal/TransformAsync.cs
index cd9ba7374..c1b8daa5f 100644
--- a/src/DynamicData/List/Internal/TransformAsync.cs
+++ b/src/DynamicData/List/Internal/TransformAsync.cs
@@ -7,7 +7,7 @@
 
 namespace DynamicData.List.Internal;
 
-internal class TransformAsync<TSource, TDestination>
+internal sealed class TransformAsync<TSource, TDestination>
     where TSource : notnull
     where TDestination : notnull
 {