refactor(historian): one QuestDbTimeClusters helper for writer + updater existence reads; redelivery tombstone test

Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe
2026-10-11 02:32:11 -04:00
parent d2be213e86
commit 3244f9781a
8 changed files with 152 additions and 91 deletions
@@ -0,0 +1,62 @@
+using Shouldly;
+using Xunit;
+
+namespace ZB.MOM.WW.OtOpcUa.Driver.Historian.QuestDb.Tests;
+
+/// <summary>
+///     The shared existence-query clustering (moved here, names unchanged, from the writer's <c>WriteTests</c> and the
+///     updater's <c>UpdateTests</c> when the two private copies were consolidated into <see cref="QuestDbTimeClusters"/>).
+/// </summary>
+public sealed class QuestDbTimeClustersTests
+{
+    private static readonly DateTime T0 = new(2026, 3, 1, 12, 0, 0, DateTimeKind.Utc);
+
+    [Fact]
+    public void Cluster_splits_on_a_gap_over_the_limit_and_at_the_per_cluster_cap()
+    {
+        var g = TimeSpan.FromMinutes(1);
+        QuestDbTimeClusters.Cluster([], g, 10).ShouldBeEmpty();
+        QuestDbTimeClusters.Cluster([T0], g, 10).ShouldBe([(T0, T0)]);
+        // exactly the gap stays together; one tick over splits
+        QuestDbTimeClusters.Cluster([T0, T0 + g], g, 10).ShouldBe([(T0, T0 + g)]);
+        QuestDbTimeClusters.Cluster([T0, T0 + g + TimeSpan.FromTicks(10)], g, 10)
+            .ShouldBe([(T0, T0), (T0 + g + TimeSpan.FromTicks(10), T0 + g + TimeSpan.FromTicks(10))]);
+        // outlier gets its own range
+        var far = T0.AddYears(1);
+        QuestDbTimeClusters.Cluster([T0, T0.AddSeconds(1), far], g, 10).ShouldBe([(T0, T0.AddSeconds(1)), (far, far)]);
+        // cap: 5 close times, max 2 per cluster
+        var five = Enumerable.Range(0, 5).Select(i => T0.AddSeconds(i)).ToList();
+        QuestDbTimeClusters.Cluster(five, g, 2)
+            .ShouldBe([(five[0], five[1]), (five[2], five[3]), (five[4], five[4])]);
+    }
+
+    [Fact]
+    public void Cluster_splits_where_the_gap_exceeds_the_limit()
+    {
+        var gap = QuestDbTimeClusters.ExistenceGap;
+        var c = QuestDbTimeClusters.Cluster(
+            [T0.AddHours(2), T0, T0.AddSeconds(30), T0.AddHours(1)], gap);
+        c.ShouldBe([(T0, T0.AddSeconds(30)), (T0.AddHours(1), T0.AddHours(1)), (T0.AddHours(2), T0.AddHours(2))]);
+        QuestDbTimeClusters.Cluster([], gap).ShouldBeEmpty();
+    }
+
+    [Fact]
+    public void The_existence_gap_is_one_minute_and_the_default_cap_is_unbounded()
+    {
+        QuestDbTimeClusters.ExistenceGap.ShouldBe(TimeSpan.FromMinutes(1));
+        var many = Enumerable.Range(0, 5000).Select(i => T0.AddMilliseconds(i)).ToList();
+        QuestDbTimeClusters.Cluster(many, QuestDbTimeClusters.ExistenceGap).ShouldBe([(many[0], many[^1])]);
+    }
+
+    [Fact]
+    public void Unsorted_input_is_sorted_before_capping()
+    {
+        var times = new[] { T0.AddSeconds(3), T0, T0.AddSeconds(2), T0.AddSeconds(1) };
+        QuestDbTimeClusters.Cluster(times, TimeSpan.FromMinutes(1), 2)
+            .ShouldBe([(T0, T0.AddSeconds(1)), (T0.AddSeconds(2), T0.AddSeconds(3))]);
+    }
+
+    [Fact]
+    public void A_cap_below_one_is_rejected() =>
+        Should.Throw<ArgumentOutOfRangeException>(() => QuestDbTimeClusters.Cluster([T0], TimeSpan.FromMinutes(1), 0));
+}