Draw the History column newest first so clipping drops the oldest runs [patch]

BuildMonitor.Test/HistoryRunsTests.cs

@@ -0,0 +1,63 @@
+// Copyright (c) 2023-2026 ktsu-dev contributors
+
+namespace ktsu.BuildMonitor.Test;
+
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+/// <summary>
+/// Tests for <see cref="BuildMonitor.SelectHistoryRuns"/>.
+/// </summary>
+/// <remarks>
+/// The History column draws its indicators left to right, and a column narrower than all of them
+/// clips on the right. The newest runs therefore have to come first, so clipping drops the oldest.
+/// </remarks>
+[TestClass]
+public sealed class HistoryRunsTests
+{
+	private static readonly DateTimeOffset Start = new(2026, 1, 1, 0, 0, 0, TimeSpan.Zero);
+
+	/// <summary>
+	/// Builds runs with the given statuses, most recent first, an hour apart.
+	/// </summary>
+	private static List<Run> RunsNewestFirst(params RunStatus[] statuses) =>
+		[.. statuses.Select((status, i) => new Run { Status = status, Started = Start.AddHours(-i) })];
+
+	[TestMethod]
+	public void TheNewestRunIsDrawnFirst()
+	{
+		// Arrange
+		List<Run> branchRuns = RunsNewestFirst(RunStatus.Running, RunStatus.Success, RunStatus.Success, RunStatus.Success, RunStatus.Success);
+
+		// Act
+		List<Run> history = BuildMonitor.SelectHistoryRuns(branchRuns);
+
+		// Assert
+		CollectionAssert.AreEqual(branchRuns, history);
+	}
+
+	[TestMethod]
+	public void OnlyTheFiveNewestRunsAreShown()
+	{
+		// Arrange
+		List<Run> branchRuns = RunsNewestFirst(RunStatus.Running, RunStatus.Failure, RunStatus.Success, RunStatus.Success, RunStatus.Success, RunStatus.Failure);
+
+		// Act
+		List<Run> history = BuildMonitor.SelectHistoryRuns(branchRuns);
+
+		// Assert
+		CollectionAssert.AreEqual(branchRuns.Take(5).ToList(), history);
+	}
+
+	[TestMethod]
+	public void CanceledRunsAreSkipped()
+	{
+		// Arrange
+		List<Run> branchRuns = RunsNewestFirst(RunStatus.Canceled, RunStatus.Success, RunStatus.Failure);
+
+		// Act
+		List<Run> history = BuildMonitor.SelectHistoryRuns(branchRuns);
+
+		// Assert
+		CollectionAssert.AreEqual(branchRuns.Skip(1).ToList(), history);
+	}
+}

BuildMonitor/BuildMonitor.cs

@@ -233,7 +233,7 @@
 	/// fields actually occupy tests the bug itself, so a fixed binding is recognised as fixed and
 	/// anything else is refused rather than guessed at.
 	/// </remarks>
 	private static unsafe int? ProbeNativeImGuiTableColumnSize()
 	{
 		int csharpSize = sizeof(ImGuiTableColumn);
 		int widthGivenOffset;
@@ -332,7 +332,7 @@
 		return narrowFieldBytes == NarrowlyBoundColumnFields.Length * 2 ? csharpSize : null;
 	}
 
 	private static unsafe void SaveColumnWidth(string columnName, int columnIndex)
 	{
 		// Null means the layout probe rejected the binding, so there is no address we can trust.
 		if (NativeImGuiTableColumnSize is not int nativeStructSize)
@@ -459,7 +459,7 @@
 		SaveSettingsIfRequired();
 	}
 
 	private static void UpdateOwnerTabs()
 	{
 		// Build expected tabs based on provider type:
 		// - GitHub: one tab per owner (org/user)
@@ -468,7 +468,7 @@
 		HashSet<string> expectedTabIds = [AllOwnersTabId, LogsTabId];
 		Dictionary<string, (string Label, Action Content)> tabsToCreate = [];
 
 		foreach ((BuildProviderName providerName, BuildProvider provider) in AppData.BuildProviders)
 		{
 			if (provider is GitHub)
 			{
@@ -675,7 +675,7 @@
 		return displayName;
 	}
 
 	private static string MakeRepositoryDisplayName(Build build)
 	{
 		string repoName = build.Repository.Name;
 		string ownerName = build.Owner.Name;
@@ -749,17 +749,27 @@
 		return shouldShow;
 	}
 
-	private static void ShowBranchHistory(List<Run> branchRuns)
+	/// <summary>
+	/// Picks the runs the History column shows from a branch's runs, most recent first.
+	/// </summary>
+	/// <remarks>
+	/// The indicators are drawn left to right, and a column too narrow for all of them clips on the
+	/// right, so the newest come first: clipping then drops the oldest runs rather than the newest.
+	/// </remarks>
+	/// <param name="branchRuns">The branch's runs, most recent first.</param>
+	/// <returns>Up to five runs that were not canceled, in the order they are drawn.</returns>
+	internal static List<Run> SelectHistoryRuns(IEnumerable<Run> branchRuns)
 	{
 		const int recentRuns = 5;
 
-		List<Run> runs = [.. branchRuns
+		return [.. branchRuns
 			.Where(r => r.Status != RunStatus.Canceled)
 			.Take(recentRuns)];
+	}
 
-		runs.Reverse();
-
-		foreach (Run? run in runs)
+	private static void ShowBranchHistory(List<Run> branchRuns)
+	{
+		foreach (Run? run in SelectHistoryRuns(branchRuns))
 		{
 			ImGui.SameLine();
 			ImGuiWidgets.ColorIndicator(GetStatusColor(run.Status), true);

README.md

@@ -71,7 +71,7 @@ The main interface displays a table of all your builds grouped by workflow and b
 - **Status**: Current status (Pending, Running, Success, Failure, Canceled)
 - **Last Run**: Timestamp of when the build started
 - **Duration**: How long the build has been running or took to complete
-- **History**: Visual history of the last 5 builds on this branch
+- **History**: Visual history of the last 5 builds on this branch, newest first
 - **Progress**: Progress bar for ongoing builds
 - **ETA**: Estimated time to completion for ongoing builds
 - **Errors**: Error messages from failed builds (click to view full details)