Add TestDatabaseContextFactory

tests/Tgstation.Server.Host.Tests/Core/TestDatabaseContextFactory.cs

@@ -0,0 +1,56 @@
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Moq;
+using System;
+using System.Threading.Tasks;
+using Tgstation.Server.Host.Models;
+
+namespace Tgstation.Server.Host.Core.Tests
+{
+	[TestClass]
+	public sealed class TestDatabaseContextFactory
+	{
+		[TestMethod]
+		public void TestConstructionThrows()
+		{
+			Assert.ThrowsException<ArgumentNullException>(() => new DatabaseContextFactory(null));
+			var mockProvider = new Mock<IServiceProvider>();
+			mockProvider.Setup(x => x.GetService(typeof(IDatabaseContext))).Verifiable();
+			var mockScope = new Mock<IServiceScope>();
+			mockScope.SetupGet(x => x.ServiceProvider).Returns(mockProvider.Object).Verifiable();
+			var mockScopeFactory = new Mock<IServiceScopeFactory>();
+			mockScopeFactory.Setup(x => x.CreateScope()).Returns(mockScope.Object).Verifiable();
+			Assert.ThrowsException<InvalidOperationException>(() => new DatabaseContextFactory(mockScopeFactory.Object));
+			mockScopeFactory.VerifyAll();
+			mockScope.VerifyAll();
+			mockProvider.VerifyAll();
+		}
+
+		[TestMethod]
+		public async Task TestWorks()
+		{
+			var mockDatabase = new Mock<IDatabaseContext>();
+			var mockProvider = new Mock<IServiceProvider>();
+			var mockDbo = mockDatabase.Object;
+			mockProvider.Setup(x => x.GetService(typeof(IDatabaseContext))).Returns(mockDbo).Verifiable();
+			var mockScope = new Mock<IServiceScope>();
+			mockScope.SetupGet(x => x.ServiceProvider).Returns(mockProvider.Object).Verifiable();
+			var mockScopeFactory = new Mock<IServiceScopeFactory>();
+			mockScopeFactory.Setup(x => x.CreateScope()).Returns(mockScope.Object).Verifiable();
+
+			var factory = new DatabaseContextFactory(mockScopeFactory.Object);
+
+			await Assert.ThrowsExceptionAsync<ArgumentNullException>(() => factory.UseContext(null)).ConfigureAwait(false);
+
+			await factory.UseContext(context =>
+			{
+				Assert.AreSame(mockDbo, context);
+				return Task.CompletedTask;
+			});
+
+			mockScopeFactory.VerifyAll();
+			mockScope.VerifyAll();
+			mockProvider.VerifyAll();
+		}
+	}
+}