Grouping by a nested dynamic property differs from grouping by a nested standard property

[clemvnt]

Hello,

I have a case where I want to group by a nested dynamic property.

The result is not the same as when I group by a nested standard property.

Is there an explanation for this or is it a bug?

Assemblies affected

Microsoft.AspNetCore.OData 8.2.5

Reproduce steps

1. Clone the repository : https://github.com/clemvnt/ODataGroupByNestedDynamicProperty
2. Run

Actual result

1. /customers => OK
2. /customers?$apply=groupby((Address/City)) => OK

[
    { "Address": { "City": "City 2" } },
    { "Address": { "City": "City 1" } }
]

3. /customers?$apply=groupby((Address/DynamicCity)) => NOK

[
    { "DynamicCity": "City 2" },
    { "DynamicCity": "City 1" }
]

Expected result

I would expect the following result for the third query :

[
    { "Address": { "DynamicCity": "City 2" } },
    { "Address": { "DynamicCity": "City 1" } }
]

[clemvnt]

By making the following changes on the Microsoft.OData.Core side, it works:
clemvnt@bb6047b

Several questions:

• Does that sound good to you? If so, I'll add the tests and make a PR.
• That seems like a breaking change to me, no?
• Since this concerns the Microsoft.OData.Core project, is it possible to move the issue to the odata.net repository?

[xuzhg]

@clemvnt Thanks for reporting this. Would you please share a PR for us to review it?

[gathogojr]

@clemvnt Thank you for reporting this issue and for the thorough investigation. To answer your questions:

• The fix looks good. Great work!
• From a behaviour perspective, this would be considered a breaking change. However, we'd be ready to make a concession here and allow this change since what we're writing to the wire is actually invalid. I'd hate to imagine that anyone is taking a dependency on this invalid payload
• We have transferred the issue to the right repo

Kindly create a pull request and add some tests. We'll be happy to review.
Thanks