PR feedback

Author: anderson-joyle

src/libraries/Microsoft.PowerFx.Core/Public/Values/CollectionTableValue.cs

@@ -184,7 +184,7 @@ public override DValue<RecordValue> Last(bool mutationCopy = false)
         public override async Task<DValue<BooleanValue>> RemoveAsync(IEnumerable<FormulaValue> recordsToRemove, bool all, CancellationToken cancellationToken)
         {
             var ret = false;
-            var markedToDeletion = new HashSet<T>();
+            var markedToDeletionIndexes = new HashSet<int>();
             var errors = new List<ExpressionError>();
 
             cancellationToken.ThrowIfCancellationRequested();
@@ -194,26 +194,29 @@ public override async Task<DValue<BooleanValue>> RemoveAsync(IEnumerable<Formula
                 return await base.RemoveAsync(recordsToRemove, all, cancellationToken).ConfigureAwait(false);
             }
 
+            var rowsArray = _enumerator.ToArray();
+
             foreach (RecordValue recordToRemove in recordsToRemove)
             {
                 var found = false;
 
-                foreach (T item in _enumerator)
+                for (int i = 0; i < rowsArray.Length; i++)
                 {
                     cancellationToken.ThrowIfCancellationRequested();
 
+                    var item = rowsArray[i];
                     DValue<RecordValue> dRecord = Marshal(item);
 
                     if (await MatchesAsync(dRecord.Value, recordToRemove, cancellationToken).ConfigureAwait(false))
                     {
-                        if (markedToDeletion.Contains(item))
+                        if (markedToDeletionIndexes.Contains(i))
                         {
                             continue;
                         }
                         else
                         {
                             found = true;
-                            markedToDeletion.Add(item);
+                            markedToDeletionIndexes.Add(i);
                         }
 
                         if (!all)
@@ -230,9 +233,9 @@ public override async Task<DValue<BooleanValue>> RemoveAsync(IEnumerable<Formula
                 }
             }
 
-            foreach (var delete in markedToDeletion)
+            foreach (var index in markedToDeletionIndexes)
             {
-                _sourceList.Remove(delete);
+                _sourceList.Remove(rowsArray[index]);
                 ret = true;
             }