diff --git a/gtsam/symbolic/tests/testVariableIndex.cpp b/gtsam/symbolic/tests/testVariableIndex.cpp
index 580f5a1a4..7aa5f971b 100644
--- a/gtsam/symbolic/tests/testVariableIndex.cpp
+++ b/gtsam/symbolic/tests/testVariableIndex.cpp
@@ -79,7 +79,7 @@ TEST(VariableIndex, augment2) {
 
   VariableIndex expected(fgCombined);
 
-  FastVector<size_t> newIndices = list_of(5)(6)(7)(8);
+  FactorIndices newIndices = list_of(5)(6)(7)(8);
   VariableIndex actual(fg1);
   actual.augment(fg2, newIndices);