added toList() for Doc|Doc[]

1 files changed, 4 insertions, 0 deletions

diff --git a/src/fields/Types.ts b/src/fields/Types.ts
index 57a310f6d..26196d15d 100644
--- a/src/fields/Types.ts
+++ b/src/fields/Types.ts
@@ -86,6 +86,10 @@ export function Cast<T extends CastCtor>(field: FieldResult, ctor: T, defaultVal
     return defaultVal === null ? undefined : defaultVal;
 }
 
+export function toList(doc: Doc | Doc[]) {
+    return doc instanceof Doc ? [doc] : doc;
+}
+
 export function DocCast(field: FieldResult, defaultVal?: Doc) {
     const doc = Cast(field, Doc, null);
     return doc && !(doc instanceof Promise) ? doc : (defaultVal as Doc);