ColumnNames to work with array untyped object

microsoft · Aug 19, 2024 · ba4e4cf · ba4e4cf
1 parent 7f591a3
commit ba4e4cf
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Showing 2 changed files with 15 additions and 4 deletions.
diff --git a/src/libraries/Microsoft.PowerFx.Interpreter/Functions/LibraryUntypedObject.cs b/src/libraries/Microsoft.PowerFx.Interpreter/Functions/LibraryUntypedObject.cs
@@ -437,7 +437,7 @@ public static FormulaValue ColumnNames_UO(IRContext irContext, UntypedObjectValu
         {
             var impl = args[0].Impl;
 
-            if (impl.Type is ExternalType externalType && externalType.Kind == ExternalTypeKind.Object)
+            if (impl.Type is ExternalType externalType && (externalType.Kind == ExternalTypeKind.Object || externalType.Kind == ExternalTypeKind.ArrayAndObject))
             {
                 if (impl.TryGetPropertyNames(out var propertyNames))
                 {

diff --git a/src/tests/Microsoft.PowerFx.Interpreter.Tests.Shared/PadUntypedObjectTests.cs b/src/tests/Microsoft.PowerFx.Interpreter.Tests.Shared/PadUntypedObjectTests.cs
@@ -177,8 +177,7 @@ public void PadUntypedObject2ColumnNamesTest()
 
             var result = engine.Eval(@"ColumnNames(Index(padTable, 1))");
 
-            // would expect not to be an error value
-            Assert.IsType<ErrorValue>(result);
+            Assert.IsAssignableFrom<TableValue>(result);
         }
 
         private DataTable GetDataTable()
@@ -588,7 +587,19 @@ public override bool TryGetProperty(string propertyName, out IUntypedObject resu
         }
 
         public override bool TryGetPropertyNames(out IEnumerable<string> result)
-        {
+        {
+            if (DataTable != null)
+            {
+                result = DataTable.Columns.Cast<DataColumn>().Select(c => c.ColumnName);
+                return true;
+            }
+
+            if (DataRow != null)
+            {
+                result = DataRow.Table.Columns.Cast<DataColumn>().Select(c => c.ColumnName);
+                return true;
+            }
+
             result = null;
             return false;
         }