generate_typetext: better handling of only-optional cases

diff --git a/src/PVE/JSONSchema.pm b/src/PVE/JSONSchema.pm
index f36ee42..45ce5ba 100644 (file)
--- a/src/PVE/JSONSchema.pm
+++ b/src/PVE/JSONSchema.pm
@@ -1317,11 +1317,11 @@ sub generate_typetext {
        &$add($key);
        $pre = ', ';
     }
-    $pre = ' [,' if $pre;
+    $pre = $pre ? ' [,' : '[';
+    $post = ']';
     foreach my $key (@optional) {
        &$add($key);
        $pre = ' [,';
-       $post = ']';
     }
     return $typetext;
 }