Revert uniq to main

attribute/set.go

@@ -263,16 +263,23 @@ func NewSetWithSortableFiltered(kvs []KeyValue, tmp *Sortable, filter Filter) (S
 
 	*tmp = nil
 
-	// Use filteredToFront here for last-value-wins semantics.
-	prev := kvs[n-1].Key
-	uniq := filteredToFront(kvs[:n-1], func(kv KeyValue) bool {
-		if kv.Key == prev {
-			return false
+	position := len(kvs) - 1
+	offset := position - 1
+
+	// The requirements stated above require that the stable
+	// result be placed in the end of the input slice, while
+	// overwritten values are swapped to the beginning.
+	//
+	// De-duplicate with last-value-wins semantics.  Preserve
+	// duplicate values at the beginning of the input slice.
+	for ; offset >= 0; offset-- {
+		if kvs[offset].Key == kvs[position].Key {
+			continue
 		}
-		prev = kv.Key
-		return true
-	})
-	kvs = kvs[uniq:]
+		position--
+		kvs[offset], kvs[position] = kvs[position], kvs[offset]
+	}
+	kvs = kvs[position:]
 
 	if filter != nil {
 		// TODO (MrAlias): there is a potential optimization here where the