Projections don't work for Marten nested objects

[stef-bulteel]

Product

Hot Chocolate

Version

15.1.12

Link to minimal reproduction

https://github.com/stef-bulteel/HCMartenBug

Steps to reproduce

Run the project
Test both queries in README.md

What is expected?

It is expected Projections "just work" per https://chillicream.com/docs/hotchocolate/v15/integrations/marten#projections

What is actually happening?

An error is thrown as soon as nested data is trying to be queried.
No actual query is launched against postgres.

Relevant log output

{
  "errors": [
    {
      "message": "Unexpected Execution Error",
      "locations": [
        {
          "line": 2,
          "column": 3
        }
      ],
      "path": [
        "products"
      ],
      "extensions": {
        "message": "Value cannot be null. (Parameter 'key')",
        "stackTrace": "   at System.Collections.Generic.Dictionary`2.set_Item(TKey key, TValue value)\r\n   at Marten.Linq.Parsing.SelectParser.VisitConstant(ConstantExpression node) in /_/src/Marten/Linq/Parsing/SelectParser.cs:line 79\r\n   at Marten.Linq.Parsing.SelectParser.Visit(Expression node) in /_/src/Marten/Linq/Parsing/SelectParser.cs:line 34\r\n   at System.Linq.Expressions.ExpressionVisitor.VisitBinary(BinaryExpression node)\r\n   at Marten.Linq.Parsing.SelectParser.VisitBinary(BinaryExpression node) in /_/src/Marten/Linq/Parsing/SelectParser.cs:line 66\r\n   at Marten.Linq.Parsing.SelectParser.Visit(Expression node) in /_/src/Marten/Linq/Parsing/SelectParser.cs:line 34\r\n   at System.Linq.Expressions.ExpressionVisitor.VisitConditional(ConditionalExpression node)\r\n   at Marten.Linq.Parsing.SelectParser.Visit(Expression node) in /_/src/Marten/Linq/Parsing/SelectParser.cs:line 34\r\n   at Marten.Linq.Parsing.SelectParser.ReadBinding(MemberAssignment binding) in /_/src/Marten/Linq/Parsing/SelectParser.cs:line 116\r\n   at Marten.Linq.Parsing.SelectParser.VisitMemberInit(MemberInitExpression node) in /_/src/Marten/Linq/Parsing/SelectParser.cs:line 96\r\n   at Marten.Linq.Parsing.SelectParser.Visit(Expression node) in /_/src/Marten/Linq/Parsing/SelectParser.cs:line 34\r\n   at Marten.Linq.Parsing.SelectParser..ctor(ISerializer serializer, IQueryableMemberCollection members, Expression expression) in /_/src/Marten/Linq/Parsing/SelectParser.cs:line 27\r\n   at Marten.Linq.Parsing.SelectorVisitor.ToSelectTransform(Expression selectExpression, ISerializer serializer) in /_/src/Marten/Linq/Parsing/SelectorVisitor.cs:line 119\r\n   at Marten.Linq.Parsing.SelectorVisitor.VisitMemberInit(MemberInitExpression node) in /_/src/Marten/Linq/Parsing/SelectorVisitor.cs:line 78\r\n   at Marten.Linq.Parsing.SelectorVisitor.Visit(Expression node) in /_/src/Marten/Linq/Parsing/SelectorVisitor.cs:line 28\r\n   at Marten.Linq.CollectionUsage.BuildTopStatement(IMartenSession session, IQueryableMemberCollection collection, IDocumentStorage storage, QueryStatistics statistics) in /_/src/Marten/Linq/CollectionUsage.Compilation.cs:line 74\r\n   at Marten.Linq.Parsing.LinqQueryParser.BuildStatements() in /_/src/Marten/Linq/Parsing/LinqQueryParser.Statements.cs:line 33\r\n   at Marten.Linq.Parsing.LinqQueryParser.BuildHandler[TResult]() in /_/src/Marten/Linq/Parsing/LinqQueryParser.Handlers.cs:line 58\r\n   at Marten.Linq.MartenLinqQueryProvider.Execute[TResult](Expression expression) in /_/src/Marten/Linq/MartenLinqQueryProvider.cs:line 56\r\n   at Marten.Linq.MartenLinqQueryable`1.GetEnumerator() in /_/src/Marten/Linq/MartenLinqQueryable.cs:line 136\r\n   at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)\r\n   at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)\r\n   at HotChocolate.DefaultQueryableExecutable`1.<ToAsyncEnumerable>b__19_0()\r\n   at System.Threading.Tasks.Task`1.InnerInvoke()\r\n   at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state)\r\n--- End of stack trace from previous location ---\r\n   at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state)\r\n   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot, Thread threadPoolThread)\r\n--- End of stack trace from previous location ---\r\n   at HotChocolate.DefaultQueryableExecutable`1.ToAsyncEnumerable(CancellationToken cancellationToken)+MoveNext()\r\n   at HotChocolate.DefaultQueryableExecutable`1.ToAsyncEnumerable(CancellationToken cancellationToken)+System.Threading.Tasks.Sources.IValueTaskSource<System.Boolean>.GetResult()\r\n   at HotChocolate.Types.Pagination.QueryableCursorPagingHandler`1.QueryExecutor.QueryAsync(IQueryable`1 slicedQuery, IQueryable`1 originalQuery, Int32 offset, Boolean includeTotalCount, CancellationToken cancellationToken)\r\n   at HotChocolate.Types.Pagination.QueryableCursorPagingHandler`1.QueryExecutor.QueryAsync(IQueryable`1 slicedQuery, IQueryable`1 originalQuery, Int32 offset, Boolean includeTotalCount, CancellationToken cancellationToken)\r\n   at HotChocolate.Types.Pagination.CursorPagingHandler`2.SliceAsync(IResolverContext context, TQuery originalQuery, CursorPagingArguments arguments, CursorPaginationAlgorithm`2 algorithm, ICursorPaginationQueryExecutor`2 executor, CancellationToken cancellationToken)\r\n   at HotChocolate.Types.Pagination.QueryableCursorPagingHandler`1.SliceAsyncInternal(IResolverContext context, IQueryableExecutable`1 source, CursorPagingArguments arguments)\r\n   at HotChocolate.Types.Pagination.CursorPagingHandler.HotChocolate.Types.Pagination.IPagingHandler.SliceAsync(IResolverContext context, Object source)\r\n   at HotChocolate.Types.Pagination.PagingMiddleware.InvokeAsync(IMiddlewareContext context)\r\n   at HotChocolate.Execution.Processing.Tasks.ResolverTask.ExecuteResolverPipelineAsync(CancellationToken cancellationToken)\r\n   at HotChocolate.Execution.Processing.Tasks.ResolverTask.TryExecuteAsync(CancellationToken cancellationToken)"
      }
    }
  ],
  "data": {
    "products": null
  }
}

Additional context

No response