Support type cast in group by

[clemvnt]

Hello,

Cast type support in group by.

This PR needs OData/odata.net#2879.

Issues

#1180

Description

For the following group by : groupby((MyAddress/Fully.Qualified.Namespace.HomeAddress/HomeNO))

The response was an error :

System.NotSupportedException: The query specified in the URI is not valid. Binding OData QueryNode of kind 'SingleResourceCast' is not supported by 'AggregationBinder'.

Now, the response is :

[
  {
    "myAddress": {
        "homeNO": "Value1"
    }
  },
  {
    "myAddress": {
        "homeNO": "Value2"
    }
  }
]

[clemvnt]

@microsoft-github-policy-service agree

[wachugamaina]

Could we stick with using var for consistency ?

[clemvnt]

This method is based on the following method :

AspNetCoreOData/src/Microsoft.AspNetCore.OData/Query/Expressions/QueryBinder.cs

Lines 692 to 703 in 7e2e707

	public virtual Expression BindSingleResourceCastNode(SingleResourceCastNode node, QueryBinderContext context)
	{
	CheckArgumentNull(node, context);
	IEdmStructuredTypeReference structured = node.StructuredTypeReference;
	Contract.Assert(structured != null, "NS casts can contain only structured types");
	Type clrType = context.Model.GetClrType(structured);
	Expression source = BindCastSourceNode(node.Source, context);
	return Expression.TypeAs(source, clrType);
	}

There doesn't seem to be any consistency between explicit types and var in the project.

But if someone of the organization feels the same way, I'll make the changes.

[wachugamaina]

Could we stick with using var for consistency ?

[clemvnt]

See previous comment.

[wachugamaina]

Could we stick with using var for consistency ?

[clemvnt]

See previous comment.

[wachugamaina]

Could we document these public classes and methods ?

[clemvnt]

Here, we're in a test file, so the other classes in this file have no comments.

But if someone of the organization feels the same way, I'll make the changes.