public void TestManual_Cant_AttachOverlappingGraphsFromDifferentContexts()
{
// Read Bills with only Courses loaded
ManualBillEntity bill0;
using (var context = new ManualDbContext())
{
bill0 = context.Bills.Include(x => x.Courses).Single();
}
// Read first Meal with Courses loaded
ManualMealEntity meal0;
using (var context = new ManualDbContext())
{
meal0 = context.Meals.Include(x => x.Courses).First();
}
// Now try and attach the graphs
using (var context = new ManualDbContext())
{
context.Set <ManualMealEntity>().Attach(meal0);
// Overlapping graph should fail
var threwException = false;
try
{
context.Set <ManualBillEntity>().Attach(bill0); // Throwing an exception is not helpful
}
catch (InvalidOperationException)
{
threwException = true;
}
finally
{
Assert.IsTrue(threwException, "EF should screw you over because it doesn't know what to do with the conflict (type and key match, but different object instance)");
}
}
}
public void TestManual_Can_AttachFullRootAndTouchTheChildren()
{
// Test we can attach Bill and touch all his children
var bill = EntityMapper.ToManualBill(Values.Bill);
using (var context = new ManualDbContext())
{
// Attach object graph
context.Set <ManualBillEntity>().Attach(bill);
// Touch them AND make them dirty
bill.LastUpdated = DateTime.Now;
context.Entry(bill).State = EntityState.Modified;
foreach (var foodCourse in bill.Courses)
{
foodCourse.LastUpdated = DateTime.Now;
context.Entry(foodCourse).State = EntityState.Modified;
}
foreach (var meal in bill.Meals)
{
meal.LastUpdated = DateTime.Now;
context.Entry(meal).State = EntityState.Modified;
}
// Save
var rowsAffected = context.SaveChanges();
// All 6 entities should be modified
Assert.AreEqual(6, rowsAffected, "Rows affected mismatch");
}
}