content: /*
   * Copyright 2022 The FeatHub Authors
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     https://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.alibaba.feathub.flink.udf.aggregation;
  
  import org.apache.flink.table.api.DataTypes;
  
  import org.junit.jupiter.api.Test;
  
  import static org.assertj.core.api.Assertions.assertThat;
  
  /** Test for {@link FirstLastValueAggFunc}. */
  class FirstLastValueAggFuncTest {
      @Test
      void tesFirstValue() {
          testFirstValueInternal(new FirstLastValueAggFunc<>(DataTypes.INT(), true), true);
          testFirstValueInternal(
                  new FirstLastValueAggFuncWithoutRetract<>(DataTypes.INT(), true), false);
      }
  
      private void testFirstValueInternal(
              final FirstLastValueAggFunc<Integer> aggFunc, boolean testRetract) {
          final FirstLastValueAggFunc.FirstLastValueAccumulator<Integer> accumulator =
                  aggFunc.createAccumulator();
          assertThat(aggFunc.getResult(accumulator)).isNull();
          aggFunc.add(accumulator, 0, 0);
          aggFunc.add(accumulator, 1, 1);
          aggFunc.add(accumulator, 2, 2);
          aggFunc.add(accumulator, 3, 3);
          assertThat(aggFunc.getResult(accumulator)).isEqualTo(0);
          if (testRetract) {
              aggFunc.retract(accumulator, 0);
              assertThat(aggFunc.getResult(accumulator)).isEqualTo(1);
          }
      }
  
      @Test
      void testLastValue() {
          testLastValueInternal(new FirstLastValueAggFunc<>(DataTypes.INT(), false), true);
          testLastValueInternal(
                  new FirstLastValueAggFuncWithoutRetract<>(DataTypes.INT(), false), false);
      }
  
      private void testLastValueInternal(
              final FirstLastValueAggFunc<Integer> aggFunc, boolean testRetract) {
          final FirstLastValueAggFunc.FirstLastValueAccumulator<Integer> accumulator =
                  aggFunc.createAccumulator();
          assertThat(aggFunc.getResult(accumulator)).isNull();
          aggFunc.add(accumulator, 0, 0);
          aggFunc.add(accumulator, 1, 1);
          aggFunc.add(accumulator, 2, 2);
          aggFunc.add(accumulator, 3, 3);
          assertThat(aggFunc.getResult(accumulator)).isEqualTo(3);
          if (testRetract) {
              aggFunc.retract(accumulator, 0);
              assertThat(aggFunc.getResult(accumulator)).isEqualTo(3);
          }
      }
  }
  