ef core 5 InMemory 测试

Question

我正在从 net core 3.1 迁移到 net 5 使用 ef core 的 net core 3.1 测试存储库正在通过，但升级到 net core 5 后，dbContext 上的 SaveChanges 抛出 nullreferenceException

这是堆栈跟踪

at Microsoft.EntityFrameworkCore.Storage.ValueConversion.ValueConverter`2.<>c__DisplayClass3_0`2.<SanitizeConverter>b__0(Object v)
   at Microsoft.EntityFrameworkCore.InMemory.Storage.Internal.InMemoryTable`1.SnapshotValue(IProperty property, ValueComparer comparer, IUpdateEntry entry)
   at Microsoft.EntityFrameworkCore.InMemory.Storage.Internal.InMemoryTable`1.<>c__DisplayClass18_0.<Create>b__0(IProperty p)
   at System.Linq.Enumerable.SelectEnumerableIterator`2.ToArray()
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
   at Microsoft.EntityFrameworkCore.InMemory.Storage.Internal.InMemoryTable`1.Create(IUpdateEntry entry)
   at Microsoft.EntityFrameworkCore.InMemory.Storage.Internal.InMemoryStore.ExecuteTransaction(IList`1 entries, IDiagnosticsLogger`1 updateLogger)
   at Microsoft.EntityFrameworkCore.InMemory.Storage.Internal.InMemoryDatabase.SaveChanges(IList`1 entries)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChanges(IList`1 entriesToSave)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChanges(DbContext _, Boolean acceptAllChangesOnSuccess)
   at Microsoft.EntityFrameworkCore.Storage.NonRetryingExecutionStrategy.Execute[TState,TResult](TState state, Func`3 operation, Func`3 verifySucceeded)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChanges(Boolean acceptAllChangesOnSuccess)
   at Microsoft.EntityFrameworkCore.DbContext.SaveChanges(Boolean acceptAllChangesOnSuccess)
   at Microsoft.EntityFrameworkCore.DbContext.SaveChanges()

用于测试的 dbContext 是使用这些选项创建的

var options = new DbContextOptionsBuilder<DcmCockpitDbContext>()
                .UseInMemoryDatabase(Guid.NewGuid().ToString())
                .Options;

            using (_context = new DcmCockpitDbContext(options, null))
            {
                SeedDatabase(_context);
            }

是否有任何会引发此异常的重大更改？ 我应该怎么做才能避免这种情况？

Answer 1

经过长时间的调试，问题来自缺少依赖项。