AlterTableImpl extends BaseSqlPart implements AlterTable { @Nullable @Override public SqlPart previous() { return mPrevious; } AlterTableImpl(@Nullable final String databaseName, @NotNull final String tableName, @NotNull final SqlPart previous); @NotNull @Override RenameTo renameTo(@NotNull final String newTableName); @NotNull @Override AddColumn add(@NotNull final Column column); @NotNull @Override AddColumn addColumn(@NotNull final Column column); @Override void prependTo(@NotNull final RawSqlBuilder builder); @Nullable @Override SqlPart previous();  }
@Test public void previous_returnsProperItem() { SqlPart sqlPart = mock(SqlPart.class); AlterTableImpl table = new AlterTableImpl("", "", sqlPart); SqlPart result = table.previous(); assertThat(result, is(sqlPart)); }