tests: Add test for issue 11653, but with Datastore

It looks like the Datastore emulator is not impacted in the way that
the Firestore emulator is.

issues/Issue11653b/Issue11653b.csproj

@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Google.Cloud.Datastore.V1" Version="4.7.0" />
+  </ItemGroup>
+
+</Project>

issues/Issue11653b/Issue11653b.sln

@@ -0,0 +1,25 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.8.34408.163
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Issue11653b", "Issue11653b.csproj", "{1B9AE535-B811-43D9-A56E-8B236B9E76B9}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{1B9AE535-B811-43D9-A56E-8B236B9E76B9}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{1B9AE535-B811-43D9-A56E-8B236B9E76B9}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{1B9AE535-B811-43D9-A56E-8B236B9E76B9}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{1B9AE535-B811-43D9-A56E-8B236B9E76B9}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {4AB11F66-05AB-4096-B85A-35AA34842012}
+	EndGlobalSection
+EndGlobal

issues/Issue11653b/Program.cs

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+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at 
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software 
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and 
+// limitations under the License.
+
+using Google.Api.Gax;
+using Google.Cloud.Datastore.V1;
+using Grpc.Core;
+
+if (args.Length != 2)
+{
+    Console.WriteLine("Arguments: <emulator-host> <project-id>");
+    Console.WriteLine("(The DATASTORE_EMULATOR_HOST environment variable is ignored.)");
+    return;
+}
+
+Environment.SetEnvironmentVariable("DATASTORE_EMULATOR_HOST", args[0]);
+
+var db = new DatastoreDbBuilder
+{
+    ProjectId = args[1],
+    EmulatorDetection = EmulatorDetection.EmulatorOnly
+}.Build();
+
+var keyFactory = db.CreateKeyFactory("test");
+var entityKey = keyFactory.CreateKey("testid");
+await Try("Allocate ID", () => db.AllocateIdAsync(keyFactory.CreateIncompleteKey()));
+await Try("Insert entity", () => db.InsertAsync(new Entity { Key = entityKey, Properties = { { "key", "value" } } }));
+await Try("Get entity", () => db.LookupAsync(entityKey));
+
+async Task Try(string description, Func<Task> taskProvider)
+{
+    try
+    {
+        await taskProvider();
+        Console.WriteLine($"'{description}' RPC succeeded");
+    }
+    catch (RpcException e)
+    {
+        Console.WriteLine($"'{description}' RPC failed: {e.Message}");
+    }
+    catch (Exception e)
+    {
+        Console.WriteLine($"'{description}' failed more dramatically: {e.GetType()}: {e.Message}");
+    }
+}