fix (#404)

Author: bitfaster

BitFaster.Caching.UnitTests/Lru/ConcurrentLruTests.cs

@@ -866,6 +866,25 @@ public void WhenItemsExistClearRemovesAllItems()
             lru.HotCount.Should().Be(0);
             lru.WarmCount.Should().Be(0);
             lru.ColdCount.Should().Be(0);
+        }
+
+        [Fact]
+        public void WhenWarmThenClearedIsWarmIsReset()
+        {
+            for (int i = 0; i < 20; i++)
+            { 
+                lru.GetOrAdd(i, k => k.ToString()); 
+            }
+
+            lru.Clear();
+            lru.Count.Should().Be(0);
+
+            for (int i = 0; i < 20; i++)
+            { 
+                lru.GetOrAdd(i, k => k.ToString()); 
+            }
+
+            lru.Count.Should().Be(capacity.Hot + capacity.Warm + capacity.Cold);
         }
 
         [Fact]

BitFaster.Caching/Lru/ConcurrentLruCore.cs

@@ -430,6 +430,8 @@ public void Clear()
                 CycleWarmUnchecked(ItemRemovedReason.Cleared);
                 TryRemoveCold(ItemRemovedReason.Cleared);
             }
+
+            Volatile.Write(ref this.isWarm, false);
         }
 
         /// <summary>