String generateUpgradeSource({List<String> changeList })

Dart code to upgrade expectedColumnNames to actualColumnNames.

Source 

String generateUpgradeSource({List<String> changeList}) {
  var setString = "null";
  if (actualColumnNames.isNotEmpty) {
    setString = "[${actualColumnNames.map((s) => '"$s"').join(",")}]";
  }

  changeList?.add("Setting unique column constraint of '$_tableName' to $setString.");

  return """
database.alterTable("$_tableName", (t) {
t.uniqueColumnSet = $setString;
});
  """;
}