From 2921b16e7509f86e4b27971b026c2c0e944ce3ed Mon Sep 17 00:00:00 2001
From: jas-valgotar <jasvalgotar@microsoft.com>
Date: Thu, 23 Jan 2025 14:33:42 -0500
Subject: [PATCH] adds Supported features check.

---
 .../Microsoft.PowerFx.Connectors/Public/CdpTableValue.cs    | 5 +++++
 .../Public/Values/DelegationParameters.cs                   | 6 +++---
 .../Microsoft.PowerFx.Core/Public/Values/TableValue.cs      | 5 +++++
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/libraries/Microsoft.PowerFx.Connectors/Public/CdpTableValue.cs b/src/libraries/Microsoft.PowerFx.Connectors/Public/CdpTableValue.cs
index cbb4651f56..c299b76506 100644
--- a/src/libraries/Microsoft.PowerFx.Connectors/Public/CdpTableValue.cs
+++ b/src/libraries/Microsoft.PowerFx.Connectors/Public/CdpTableValue.cs
@@ -44,6 +44,11 @@ internal CdpTableValue(IRContext irContext)
 
         public override IEnumerable<DValue<RecordValue>> Rows => GetRowsAsync(null, null, CancellationToken.None).ConfigureAwait(false).GetAwaiter().GetResult();
 
+        public DelegationParameterFeatures SupportedFeatures => DelegationParameterFeatures.Filter |
+                DelegationParameterFeatures.Top |
+                DelegationParameterFeatures.Columns | // $select
+                DelegationParameterFeatures.Sort; // $orderby
+
         public async Task<IReadOnlyCollection<DValue<RecordValue>>> GetRowsAsync(IServiceProvider services, DelegationParameters parameters, CancellationToken cancel)
         {
             if (parameters == null && _cachedRows != null)
diff --git a/src/libraries/Microsoft.PowerFx.Core/Public/Values/DelegationParameters.cs b/src/libraries/Microsoft.PowerFx.Core/Public/Values/DelegationParameters.cs
index a4a4f2dde8..d328e8d425 100644
--- a/src/libraries/Microsoft.PowerFx.Core/Public/Values/DelegationParameters.cs
+++ b/src/libraries/Microsoft.PowerFx.Core/Public/Values/DelegationParameters.cs
@@ -76,15 +76,15 @@ public enum DelegationParameterFeatures
         // $apply = groupby((field1, ..), field with sum as TotalSum)
         ApplyGroupBy = 1 << 5,
 
+        // $count
+        Count = 1 << 6,
+
         /*
           To be implemented later when needed
          
         // $compute
         Compute = 1 << 5,
 
-        // $count
-        Count = 1 << 6,
-
         // $expand
         Expand = 1 << 7,
 
diff --git a/src/libraries/Microsoft.PowerFx.Core/Public/Values/TableValue.cs b/src/libraries/Microsoft.PowerFx.Core/Public/Values/TableValue.cs
index 01debd059d..42e70f6847 100644
--- a/src/libraries/Microsoft.PowerFx.Core/Public/Values/TableValue.cs
+++ b/src/libraries/Microsoft.PowerFx.Core/Public/Values/TableValue.cs
@@ -37,6 +37,11 @@ public interface IDelegatableTableValue
         /// <param name="parameters">Delegation parameters.</param>
         /// <param name="cancel"></param>
         Task<FormulaValue> ExecuteQueryAsync(IServiceProvider services, DelegationParameters parameters, CancellationToken cancel);
+
+        /// <summary>
+        /// Supported features for delegation to verify correct Features are delegated at runtime.
+        /// </summary>
+        DelegationParameterFeatures SupportedFeatures { get; }
     }
 
     /// <summary>