fix: decrease queue once on reject

Farfetch · Mar 27, 2024 · bb61dd7 · bb61dd7
1 parent 28fd483
commit bb61dd7
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Showing 2 changed files with 18 additions and 16 deletions.
diff --git a/src/Farfetch.LoadShedding/Tasks/ConcurrentCounter.cs b/src/Farfetch.LoadShedding/Tasks/ConcurrentCounter.cs
@@ -1,4 +1,4 @@
-namespace Farfetch.LoadShedding.Tasks
+namespace Farfetch.LoadShedding.Tasks
 {
     internal class ConcurrentCounter
     {
@@ -64,10 +64,7 @@ public int Decrement()
         {
             lock (this._locker)
             {
-                if (this._count > 0)
-                {
-                    this._count--;
-                }
+                this._count--;
 
                 return this._count;
             }

diff --git a/src/Farfetch.LoadShedding/Tasks/TaskQueue.cs b/src/Farfetch.LoadShedding/Tasks/TaskQueue.cs
@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Runtime.CompilerServices;
@@ -9,7 +9,7 @@ namespace Farfetch.LoadShedding.Tasks
 {
     internal class TaskQueue
     {
-        private readonly ConcurrentCounter _counter = new ConcurrentCounter();
+        private readonly ConcurrentCounter _counter = new();
 
         private readonly IDictionary<Priority, TaskItemList> _queues = new SortedDictionary<Priority, TaskItemList>()
         {
@@ -80,11 +80,7 @@ private int EnqueueItem(TaskItem item)
         {
             this._queues[item.Priority].Add(item);
 
-            var count = this._counter.Increment();
-
-            this.OnItemEnqueued?.Invoke(count, item);
-
-            return count;
+            return IncrementCounter(item);
         }
 
         private void RejectLastItem()
@@ -99,16 +95,25 @@ private void RejectLastItem()
                 return;
             }
 
-            this._counter.Decrement();
-
             this.DecrementCounter(lastItem);
 
             lastItem.Reject();
         }
 
-        private void DecrementCounter(TaskItem nextQueueItem)
+        private int IncrementCounter(TaskItem item)
         {
-            this.OnItemDequeued?.Invoke(this._counter.Decrement(), nextQueueItem);
+            var count = this._counter.Increment();
+            this.OnItemEnqueued?.Invoke(count, item);
+
+            return count;
+        }
+
+        private int DecrementCounter(TaskItem nextQueueItem)
+        {
+            var count = this._counter.Decrement();
+            this.OnItemDequeued?.Invoke(count, nextQueueItem);
+
+            return count;
         }
     }
 }