1 files changed, 2 insertions, 0 deletions
diff --git a/src/new_fields/Doc.ts b/src/new_fields/Doc.ts
index 0d9fa540f..1dd721396 100644
--- a/src/new_fields/Doc.ts
+++ b/src/new_fields/Doc.ts
@@ -371,6 +371,8 @@ export namespace Doc {
                     copy[key] = field;
                 } else if (field instanceof ObjectField) {
                     copy[key] = ObjectField.MakeCopy(field);
+                } else if (field instanceof Promise) {
+                    field.then(f => (copy[key] === undefined) && (copy[key] = f)); //TODO what should we do here?
                 } else {
                     copy[key] = field;
                 }