NH-3673 - Closure variable values locked in from expressions in NHibernate LINQ provider

[nhibernate-bot]

David Straw created an issue — 22nd August 2014, 16:07:48:

The value of a closure variable used in a function call in an expression (ex. in Select) in the NHibernate LINQ provider gets locked in to the value that was present the first time the query gets evaluated.

Reproduction case:

class Repro
{
    private Guid MyFunc(MyType item, Guid closureValue)
    {
        return closureValue;
    }
    public object Run()
    {
        IEnumerable<Guid> result;
        var closureVariable = Guid.NewGuid();
        using (var session = mySessionFactory.OpenSession())
        {
            result = session.Query<MyType>()
                .Select(x => MyFunc(x, closureVariable))
                .ToList();
        }
        Debug.Assert(result.First() == closureVariable); // Works the first time but fails all subsequent times
        return result;
    }
}

---

Ricardo Peres added a comment — 22nd August 2014, 17:52:54:

Probably a duplicate of NH-2658.

[fredericDelaporte]

Very similar to #1363, but still not fixed while most cases of #1363 are.

[jeremycampbellaustin]

I'm wondering if this issue has surfaced again in v5.3.0. v5.2.7 does not have the issue.

public SomeEntityDto Get(int id) { _session.Query<SomeEntity>() .Where(e => e.Id == id) .Select(e => new SomeEntityDto { Id = id, Year = e.ScholarYear }).Single(); }

The first time the query is called, the Id on the returned object is correct. After the first call, the Id on the returned object is always the id from the first call. The results coming back from the database looks correct, so it appears there is something going on with the hydration of SomeEntityDto.

[cremor]

@jeremycampbellaustin You might want to create a new issue for that. I'm not sure if the developers of NHibernate monitor old issues for comments.

edit: Ok, seems like they do 😄