add method
Implementation
add(SqliteMigration migration) {
assert(
migrations.isEmpty || migrations.last.toVersion < migration.toVersion);
final down = migration.downMigration;
if (down != null) {
if (migrations.isEmpty) {
if (down.toVersion != 0) {
throw MigrationError(
'Down migration for first migration must have toVersion = 0');
}
} else {
if (down.toVersion > migrations.last.toVersion) {
throw MigrationError(
'Down migration for ${migration.toVersion} must have a toVersion <= ${migrations.last.toVersion}');
}
}
}
migrations.add(migration);
}