fix: Fixed PriorityQueue IndexOutOfRange exception when an inner queue becomes depleted

CHANGELOG.md

@@ -6,6 +6,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 
+### Changed
+ - Fixed PriorityQueue IndexOutOfRange exception when an inner queue becomes depleted
+
 ## [8.3.1] - 2019-04-05
 ### Changed
  - Fixed FormatException when parsing some JSON DateTimes

ICD.Common.Utils.Tests/Collections/PriorityQueueTest.cs

@@ -168,6 +168,29 @@ namespace ICD.Common.Utils.Tests.Collections
 			Assert.AreEqual(0, queue.Count);
 		}
 
+		[Test]
+		public void TryDequeueTest()
+		{
+			PriorityQueue<int> queue = new PriorityQueue<int>();
+			queue.Enqueue(10, 1);
+			queue.Enqueue(20, 2);
+			queue.Enqueue(30, 3);
+
+			int output;
+
+			Assert.IsTrue(queue.TryDequeue(out output));
+			Assert.AreEqual(10, output);
+
+			Assert.IsTrue(queue.TryDequeue(out output));
+			Assert.AreEqual(20, output);
+
+			Assert.IsTrue(queue.TryDequeue(out output));
+			Assert.AreEqual(30, output);
+
+			Assert.IsFalse(queue.TryDequeue(out output));
+			Assert.AreEqual(0, output);
+		}
+
 		[Test]
 		public void GetEnumeratorTest()
 		{

ICD.Common.Utils/Collections/PriorityQueue.cs

@@ -77,7 +77,7 @@ namespace ICD.Common.Utils.Collections
 			if (!m_PriorityToQueue.TryGetValue(priority, out queue))
 			{
 				queue = new List<T>();
-				m_PriorityToQueue[priority] = queue;
+				m_PriorityToQueue.Add(priority, queue);
 			}
 
 			queue.Add(item);
@@ -97,7 +97,7 @@ namespace ICD.Common.Utils.Collections
 			if (!m_PriorityToQueue.TryGetValue(priority, out queue))
 			{
 				queue = new List<T>();
-				m_PriorityToQueue[priority] = queue;
+				m_PriorityToQueue.Add(priority, queue);
 			}
 
 			queue.Insert(0, item);
@@ -136,7 +136,7 @@ namespace ICD.Common.Utils.Collections
 
 			bool inserted = false;
 
-			foreach (KeyValuePair<int, List<T>> kvp in m_PriorityToQueue)
+			foreach (KeyValuePair<int, List<T>> kvp in m_PriorityToQueue.ToArray())
 			{
 				int[] removeIndices =
 					kvp.Value
@@ -166,6 +166,9 @@ namespace ICD.Common.Utils.Collections
 
 					inserted = true;
 				}
+
+				if (kvp.Value.Count == 0)
+					m_PriorityToQueue.Remove(kvp.Key);
 			}
 
 			if (!inserted)
@@ -193,6 +196,8 @@ namespace ICD.Common.Utils.Collections
 		/// <returns></returns>
 		[PublicAPI]
 		public bool TryDequeue(out T output)
+		{
+			while (true)
 			{
 				output = default(T);
 
@@ -203,16 +208,20 @@ namespace ICD.Common.Utils.Collections
 				int priority = kvp.Key;
 				List<T> queue = kvp.Value;
 
-			output = queue[0];
+				bool found = queue.TryFirst(out output);
+				if (found)
+				{
 					queue.RemoveAt(0);
+					m_Count--;
+				}
 
 				if (queue.Count == 0)
 					m_PriorityToQueue.Remove(priority);
 
-			m_Count--;
+				if (found)
-
 					return true;
 			}
+		}
 
 		/// <summary>
 		/// Gets an enumerator for the items.
@@ -233,10 +242,7 @@ namespace ICD.Common.Utils.Collections
 		public void CopyTo(Array array, int index)
 		{
 			foreach (T item in this)
-			{
+				array.SetValue(item, index++);
-				array.SetValue(item, index);
-				index++;
-			}
 		}
 
 		#endregion