From 14508498d9f0d709e31d4d4e4e44a740cb3353c2 Mon Sep 17 00:00:00 2001
From: Brian Popow <popow@gmx.de>
Date: Tue, 23 Nov 2021 09:00:33 +0100
Subject: [PATCH] Seal classes and avoid calling SuppressFinalize

---
 .../Formats/Webp/Lossless/CostManager.cs      | 24 ++-----------------
 .../Formats/Webp/Lossless/PixOrCopy.cs        |  2 +-
 .../Formats/Webp/Lossless/Vp8LHashChain.cs    | 23 ++----------------
 3 files changed, 5 insertions(+), 44 deletions(-)

diff --git a/src/ImageSharp/Formats/Webp/Lossless/CostManager.cs b/src/ImageSharp/Formats/Webp/Lossless/CostManager.cs
index 3ee1021386..c121a41a1a 100644
--- a/src/ImageSharp/Formats/Webp/Lossless/CostManager.cs
+++ b/src/ImageSharp/Formats/Webp/Lossless/CostManager.cs
@@ -13,10 +13,8 @@ namespace SixLabors.ImageSharp.Formats.Webp.Lossless
     /// It caches the different CostCacheInterval, caches the different
     /// GetLengthCost(costModel, k) in costCache and the CostInterval's.
     /// </summary>
-    internal class CostManager : IDisposable
+    internal sealed class CostManager : IDisposable
     {
-        private bool disposed;
-
         private CostInterval head;
 
         private const int FreeIntervalsStartCount = 25;
@@ -328,25 +326,7 @@ private void UpdateCost(int i, int position, float cost)
             }
         }
 
-        protected virtual void Dispose(bool disposing)
-        {
-            if (!this.disposed)
-            {
-                if (disposing)
-                {
-                    this.Costs.Dispose();
-                }
-
-                this.disposed = true;
-            }
-        }
-
         /// <inheritdoc />
-        public void Dispose()
-        {
-            // Do not change this code. Put cleanup code in 'Dispose(bool disposing)' method
-            this.Dispose(disposing: true);
-            GC.SuppressFinalize(this);
-        }
+        public void Dispose() => this.Costs.Dispose();
     }
 }
diff --git a/src/ImageSharp/Formats/Webp/Lossless/PixOrCopy.cs b/src/ImageSharp/Formats/Webp/Lossless/PixOrCopy.cs
index 6cd109121d..96cdc3cbc5 100644
--- a/src/ImageSharp/Formats/Webp/Lossless/PixOrCopy.cs
+++ b/src/ImageSharp/Formats/Webp/Lossless/PixOrCopy.cs
@@ -6,7 +6,7 @@
 namespace SixLabors.ImageSharp.Formats.Webp.Lossless
 {
     [DebuggerDisplay("Mode: {Mode}, Len: {Len}, BgraOrDistance: {BgraOrDistance}")]
-    internal class PixOrCopy
+    internal sealed class PixOrCopy
     {
         public PixOrCopyMode Mode { get; set; }
 
diff --git a/src/ImageSharp/Formats/Webp/Lossless/Vp8LHashChain.cs b/src/ImageSharp/Formats/Webp/Lossless/Vp8LHashChain.cs
index 2aa35e392e..1bc7613a90 100644
--- a/src/ImageSharp/Formats/Webp/Lossless/Vp8LHashChain.cs
+++ b/src/ImageSharp/Formats/Webp/Lossless/Vp8LHashChain.cs
@@ -8,7 +8,7 @@
 
 namespace SixLabors.ImageSharp.Formats.Webp.Lossless
 {
-    internal class Vp8LHashChain : IDisposable
+    internal sealed class Vp8LHashChain : IDisposable
     {
         private const uint HashMultiplierHi = 0xc6a4a793u;
 
@@ -30,8 +30,6 @@ internal class Vp8LHashChain : IDisposable
 
         private readonly MemoryAllocator memoryAllocator;
 
-        private bool disposed;
-
         /// <summary>
         /// Initializes a new instance of the <see cref="Vp8LHashChain"/> class.
         /// </summary>
@@ -288,24 +286,7 @@ private static int GetWindowSizeForHashChain(int quality, int xSize)
             return maxWindowSize > WindowSize ? WindowSize : maxWindowSize;
         }
 
-        protected virtual void Dispose(bool disposing)
-        {
-            if (!this.disposed)
-            {
-                if (disposing)
-                {
-                    this.OffsetLength.Dispose();
-                }
-
-                this.disposed = true;
-            }
-        }
-
         /// <inheritdoc />
-        public void Dispose()
-        {
-            this.Dispose(disposing: true);
-            GC.SuppressFinalize(this);
-        }
+        public void Dispose() => this.OffsetLength.Dispose();
     }
 }