Fixed: Stats failing of all indexer events are failures

Fixes #1231

src/NzbDrone.Core.Test/IndexerStatsTests/IndexerStatisticsServiceFixture.cs

@@ -0,0 +1,55 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using FizzWare.NBuilder;
+using FluentAssertions;
+using Moq;
+using NUnit.Framework;
+using NzbDrone.Core.History;
+using NzbDrone.Core.Indexers;
+using NzbDrone.Core.IndexerStats;
+using NzbDrone.Core.Test.Framework;
+
+namespace NzbDrone.Core.Test.IndexerStatsTests
+{
+    public class IndexerStatisticsServiceFixture : CoreTest<IndexerStatisticsService>
+    {
+        private IndexerDefinition _indexer;
+
+        [SetUp]
+        public void Setup()
+        {
+            _indexer = Builder<IndexerDefinition>.CreateNew().With(x => x.Id = 5).Build();
+
+            Mocker.GetMock<IIndexerFactory>()
+                  .Setup(o => o.All())
+                  .Returns(new List<IndexerDefinition> { _indexer });
+        }
+
+        [Test]
+        public void should_pull_stats_if_all_events_are_failures()
+        {
+            var history = new List<History.History>
+            {
+                new History.History
+                {
+                    Date = DateTime.UtcNow.AddHours(-1),
+                    EventType = HistoryEventType.IndexerRss,
+                    Successful = false,
+                    Id = 8,
+                    IndexerId = 5,
+                    Data = new Dictionary<string, string> { { "source", "prowlarr" } }
+                }
+            };
+
+            Mocker.GetMock<IHistoryService>()
+                .Setup(o => o.Between(It.IsAny<DateTime>(), It.IsAny<DateTime>()))
+                .Returns<DateTime, DateTime>((s, f) => history);
+
+            var statistics = Subject.IndexerStatistics(DateTime.UtcNow.AddMonths(-1), DateTime.UtcNow);
+
+            statistics.IndexerStatistics.Count.Should().Be(1);
+            statistics.IndexerStatistics.First().AverageResponseTime.Should().Be(0);
+        }
+    }
+}

src/NzbDrone.Core/IndexerStats/IndexerStatisticsService.cs

@@ -56,9 +56,10 @@ namespace NzbDrone.Core.IndexerStats
                                           .ToArray();
                 int temp = 0;
 
-                indexerStats.AverageResponseTime = (int)sortedEvents.Where(h => int.TryParse(h.Data.GetValueOrDefault("elapsedTime"), out temp))
-                                                                    .Select(h => temp)
-                                                                    .Average();
+                var elapsedTimeEvents = sortedEvents.Where(h => int.TryParse(h.Data.GetValueOrDefault("elapsedTime"), out temp))
+                                                                    .Select(h => temp);
+
+                indexerStats.AverageResponseTime = elapsedTimeEvents.Count() > 0 ? (int)elapsedTimeEvents.Average() : 0;
 
                 foreach (var historyEvent in sortedEvents)
                 {