add EfMigrationsTests

DiplomaticMailBot.Tests.Integration/Tests/EfMigrationsTests.cs

@@ -0,0 +1,54 @@
+using DiplomaticMailBot.Tests.Integration.Services;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Metadata;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+namespace DiplomaticMailBot.Tests.Integration.Tests;
+
+[TestFixture]
+public sealed class EfMigrationsTests
+{
+    /* see
+     https://www.meziantou.net/detect-missing-migrations-in-entity-framework-core.htm
+     https://github.com/dotnet/efcore/issues/26348#issuecomment-1535156915
+     */
+    [Test]
+    public async Task EnsureMigrationsAreUpToDate()
+    {
+        var dbConnectionString = string.Empty;
+        var dbContextFactory = new TestDbContextFactory(dbConnectionString);
+        await using var dbContext = dbContextFactory.CreateDbContext();
+
+        // Get required services from the dbcontext
+        var migrationModelDiffer = dbContext.GetService<IMigrationsModelDiffer>();
+        var migrationsAssembly = dbContext.GetService<IMigrationsAssembly>();
+        var modelRuntimeInitializer = dbContext.GetService<IModelRuntimeInitializer>();
+        var designTimeModel = dbContext.GetService<IDesignTimeModel>();
+
+        // Get current model
+        var model = designTimeModel.Model;
+
+        // Get the snapshot model and finalize it
+        var snapshotModel = migrationsAssembly.ModelSnapshot?.Model;
+        if (snapshotModel is IMutableModel mutableModel)
+        {
+            // Forces post-processing on the model such that it is ready for use by the runtime
+            snapshotModel = mutableModel.FinalizeModel();
+        }
+
+        if (snapshotModel is not null)
+        {
+            // Validates and initializes the given model with runtime dependencies
+            snapshotModel = modelRuntimeInitializer.Initialize(snapshotModel);
+        }
+
+        // Compute differences
+        var modelDifferences = migrationModelDiffer.GetDifferences(
+            source: snapshotModel?.GetRelationalModel(),
+            target: model.GetRelationalModel());
+
+        // The differences should be empty if the migrations are up-to-date
+        Assert.That(modelDifferences, Is.Empty);
+    }
+}