Entity Framework 6 TestDbSet

gistfile1.cs

public class TestDbSet<TEntity> : DbSet<TEntity>, IQueryable, IEnumerable<TEntity>, IDbAsyncEnumerable<TEntity> 
        where TEntity : class 
{ 
	ObservableCollection<TEntity> _data; 
	IQueryable _query; 

	public TestDbSet() 
	{ 
		_data = new ObservableCollection<TEntity>(); 
		_query = _data.AsQueryable(); 
	} 

	public override TEntity Add(TEntity item) 
	{ 
		_data.Add(item); 
		return item; 
	} 

	public override TEntity Remove(TEntity item) 
	{ 
		_data.Remove(item); 
		return item; 
	} 

	public override TEntity Attach(TEntity item) 
	{ 
		_data.Add(item); 
		return item; 
	} 

	public override TEntity Create() 
	{ 
		return Activator.CreateInstance<TEntity>(); 
	} 

	public override TDerivedEntity Create<TDerivedEntity>() 
	{ 
		return Activator.CreateInstance<TDerivedEntity>(); 
	} 

	public override ObservableCollection<TEntity> Local 
	{ 
		get { return _data; } 
	} 

	Type IQueryable.ElementType 
	{ 
		get { return _query.ElementType; } 
	} 

	Expression IQueryable.Expression 
	{ 
		get { return _query.Expression; } 
	} 

	IQueryProvider IQueryable.Provider 
	{ 
		get { return new TestDbAsyncQueryProvider<TEntity>(_query.Provider); } 
	} 

	System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() 
	{ 
		return _data.GetEnumerator(); 
	} 

	IEnumerator<TEntity> IEnumerable<TEntity>.GetEnumerator() 
	{ 
		return _data.GetEnumerator(); 
	} 

	IDbAsyncEnumerator<TEntity> IDbAsyncEnumerable<TEntity>.GetAsyncEnumerator() 
	{ 
		return new TestDbAsyncEnumerator<TEntity>(_data.GetEnumerator()); 
	} 
}