chore: import upstream snapshot with attribution

dotnet/tests/Microsoft.Agents.AI.DurableTask.UnitTests/AgentSessionIdTests.cs

@@ -0,0 +1,68 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using Microsoft.DurableTask.Entities;
+
+namespace Microsoft.Agents.AI.DurableTask.UnitTests;
+
+public sealed class AgentSessionIdTests
+{
+    [Fact]
+    public void ParseValidSessionId()
+    {
+        const string Name = "test-agent";
+        const string Key = "12345";
+        string sessionIdString = $"@dafx-{Name}@{Key}";
+        AgentSessionId sessionId = AgentSessionId.Parse(sessionIdString);
+
+        Assert.Equal(Name, sessionId.Name);
+        Assert.Equal(Key, sessionId.Key);
+    }
+
+    [Fact]
+    public void ParseInvalidSessionId()
+    {
+        const string InvalidSessionIdString = "@test-agent@12345"; // Missing "dafx-" prefix
+        Assert.Throws<ArgumentException>(() => AgentSessionId.Parse(InvalidSessionIdString));
+    }
+
+    [Fact]
+    public void FromEntityId()
+    {
+        const string Name = "test-agent";
+        const string Key = "12345";
+
+        EntityInstanceId entityId = new($"dafx-{Name}", Key);
+        AgentSessionId sessionId = (AgentSessionId)entityId;
+
+        Assert.Equal(Name, sessionId.Name);
+        Assert.Equal(Key, sessionId.Key);
+    }
+
+    [Fact]
+    public void FromInvalidEntityId()
+    {
+        const string Name = "test-agent";
+        const string Key = "12345";
+
+        EntityInstanceId entityId = new(Name, Key); // Missing "dafx-" prefix
+
+        Assert.Throws<ArgumentException>(() =>
+        {
+            // This assignment should throw an exception because
+            // the entity ID is not a valid agent session ID.
+            AgentSessionId sessionId = entityId;
+        });
+    }
+
+    // Ensures the 2-arg constructor treats the key as opaque and never re-interprets
+    // it as a serialized session id, so the resulting Name always comes from the first
+    // argument regardless of the key's shape.
+    [Fact]
+    public void ConstructorTreatsKeyAsOpaqueValue()
+    {
+        AgentSessionId sessionId = new("agentA", "@dafx-agentB@some-key");
+
+        Assert.Equal("agentA", sessionId.Name);
+        Assert.Equal("@dafx-agentB@some-key", sessionId.Key);
+    }
+}