stabilizaiton work - projects rework for maintenanceability and ui livening

src/__Libraries/StellaOps.HybridLogicalClock.Tests/InMemoryHlcStateStoreTests.Load.cs

@@ -0,0 +1,54 @@
+// <copyright file="InMemoryHlcStateStoreTests.Load.cs" company="StellaOps">
+// Copyright (c) StellaOps. Licensed under BUSL-1.1.
+// </copyright>
+using FluentAssertions;
+using System;
+using System.Threading;
+using Xunit;
+
+namespace StellaOps.HybridLogicalClock.Tests;
+
+public sealed partial class InMemoryHlcStateStoreTests
+{
+    [Fact]
+    public async Task LoadAsync_NoState_ReturnsNullAsync()
+    {
+        var store = new InMemoryHlcStateStore();
+
+        var result = await store.LoadAsync("node1", CancellationToken.None);
+
+        result.Should().BeNull();
+    }
+
+    [Fact]
+    public async Task LoadAsync_NullNodeId_ThrowsArgumentNullExceptionAsync()
+    {
+        var store = new InMemoryHlcStateStore();
+
+        var act = () => store.LoadAsync(null!, CancellationToken.None);
+
+        await act.Should().ThrowAsync<ArgumentNullException>();
+    }
+
+    [Fact]
+    public async Task LoadAsync_WhitespaceNodeId_ThrowsArgumentExceptionAsync()
+    {
+        var store = new InMemoryHlcStateStore();
+
+        var act = () => store.LoadAsync("   ", CancellationToken.None);
+
+        await act.Should().ThrowAsync<ArgumentException>();
+    }
+
+    [Fact]
+    public async Task LoadAsync_Cancelled_ThrowsOperationCanceledExceptionAsync()
+    {
+        var store = new InMemoryHlcStateStore();
+        using var cts = new CancellationTokenSource();
+        cts.Cancel();
+
+        var act = () => store.LoadAsync("node1", cts.Token);
+
+        await act.Should().ThrowAsync<OperationCanceledException>();
+    }
+}