From af98672b17ca17c8fbe28a981f25fa0071a49224 Mon Sep 17 00:00:00 2001
From: Steve Sanderson <SteveSandersonMS@users.noreply.github.com>
Date: Tue, 13 Feb 2018 19:52:44 +0000
Subject: [PATCH] Remove redundant WeakValueDictionary

---
 .../RenderTree/RenderTreeDiffBuilder.cs       |  1 -
 .../Rendering/WeakValueDictionary.cs          | 61 -------------------
 2 files changed, 62 deletions(-)
 delete mode 100644 src/Microsoft.AspNetCore.Blazor/Rendering/WeakValueDictionary.cs

diff --git a/src/Microsoft.AspNetCore.Blazor/RenderTree/RenderTreeDiffBuilder.cs b/src/Microsoft.AspNetCore.Blazor/RenderTree/RenderTreeDiffBuilder.cs
index 72685e8523..14472b136c 100644
--- a/src/Microsoft.AspNetCore.Blazor/RenderTree/RenderTreeDiffBuilder.cs
+++ b/src/Microsoft.AspNetCore.Blazor/RenderTree/RenderTreeDiffBuilder.cs
@@ -2,7 +2,6 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using System.Reflection;
 using Microsoft.AspNetCore.Blazor.Components;
 using Microsoft.AspNetCore.Blazor.Rendering;
 
diff --git a/src/Microsoft.AspNetCore.Blazor/Rendering/WeakValueDictionary.cs b/src/Microsoft.AspNetCore.Blazor/Rendering/WeakValueDictionary.cs
deleted file mode 100644
index bbea21d247..0000000000
--- a/src/Microsoft.AspNetCore.Blazor/Rendering/WeakValueDictionary.cs
+++ /dev/null
@@ -1,61 +0,0 @@
-// Copyright (c) .NET Foundation. All rights reserved.
-// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
-
-using System;
-using System.Collections.Generic;
-using System.Linq;
-
-namespace Microsoft.AspNetCore.Blazor.Rendering
-{
-    internal class WeakValueDictionary<TKey, TValue> where TValue : class
-    {
-        private IDictionary<TKey, WeakReference<TValue>> _store
-            = new Dictionary<TKey, WeakReference<TValue>>();
-        private int _cullThreshold = 10;
-
-        public bool TryGetValue(TKey key, out TValue value)
-        {
-            if (_store.TryGetValue(key, out var existingWeakRef))
-            {
-                if (existingWeakRef.TryGetTarget(out value))
-                {
-                    return true;
-                }
-
-                // Since we know it's not there, we might as well drop the entry now
-                _store.Remove(key);
-            }
-
-            value = default(TValue);
-            return false;
-        }
-
-        public void Add(TKey key, TValue value)
-        {
-            if (_store.TryGetValue(key, out _))
-            {
-                throw new ArgumentException($"The given key was already present in the {nameof(WeakValueDictionary<TKey, TValue>)}. Key: {key}");
-            }
-
-            _store[key] = new WeakReference<TValue>(value);
-            CullIfApplicable();
-        }
-
-        private void CullIfApplicable()
-        {
-            if (_store.Count > _cullThreshold)
-            {
-                var itemsToRemove = _store.Where(x => !x.Value.TryGetTarget(out _)).ToList();
-                foreach (var itemToRemove in itemsToRemove)
-                {
-                    _store.Remove(itemToRemove.Key);
-                }
-
-                if (_store.Count > (_cullThreshold / 2))
-                {
-                    _cullThreshold *= 2;
-                }
-            }
-        }
-    }
-}