public DdlCommandResult execute(
      final String sql,
      final DdlCommand ddlCommand,
      final boolean withQuery,
      final Set<SourceName> withQuerySources
  ) {
    return execute(sql, ddlCommand, withQuery, withQuerySources, false);
  }
@Test
  public void shouldDropSource() {
    // Given:
    metaStore.putSource(source, false);
    givenDropSourceCommand(STREAM_NAME);

    // When:
    final DdlCommandResult result = cmdExec.execute(SQL_TEXT, dropSource, false, NO_QUERY_SOURCES);

    // Then
    assertThat(result.isSuccess(), is(true));
    assertThat(
        result.getMessage(),
        equalTo(String.format("Source %s (topic: %s) was dropped.", STREAM_NAME, TOPIC_NAME))
    );
  }