content: /*
   * Copyright 2015, 2024 StreamEx contributors
   *
   * 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
   *
   *     http://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 one.util.streamex.api;
  
  import one.util.streamex.*;
  import org.junit.FixMethodOrder;
  import org.junit.Test;
  import org.junit.runners.MethodSorters;
  
  import java.util.Map;
  import java.util.OptionalDouble;
  import java.util.stream.Collectors;
  import java.util.stream.IntStream;
  
  import static org.junit.Assert.*;
  
  /**
   * @author Tagir Valeev
   */
  @FixMethodOrder(MethodSorters.NAME_ASCENDING)
  public class DoubleCollectorTest {
      @Test
      public void testJoining() {
          String expected = IntStream.range(0, 10000).asDoubleStream().mapToObj(String::valueOf).collect(
              Collectors.joining(", "));
          assertEquals(expected, IntStreamEx.range(10000).asDoubleStream().collect(DoubleCollector.joining(", ")));
          assertEquals(expected, IntStreamEx.range(10000).asDoubleStream().parallel().collect(
              DoubleCollector.joining(", ")));
          String expected2 = IntStreamEx.range(0, 1000).asDoubleStream().boxed().toList().toString();
          assertEquals(expected2, IntStreamEx.range(1000).asDoubleStream().collect(
              DoubleCollector.joining(", ", "[", "]")));
          assertEquals(expected2, IntStreamEx.range(1000).asDoubleStream().parallel().collect(
              DoubleCollector.joining(", ", "[", "]")));
      }
  
      @Test
      public void testCounting() {
          assertEquals(5000L, (long) IntStreamEx.range(10000).asDoubleStream().atLeast(5000).collect(
              DoubleCollector.counting()));
          assertEquals(5000L, (long) IntStreamEx.range(10000).asDoubleStream().parallel().atLeast(5000).collect(
              DoubleCollector.counting()));
          assertEquals(5000, (int) IntStreamEx.range(10000).asDoubleStream().atLeast(5000).collect(
              DoubleCollector.countingInt()));
          assertEquals(5000, (int) IntStreamEx.range(10000).asDoubleStream().parallel().atLeast(5000).collect(
              DoubleCollector.countingInt()));
      }
  
      @Test
      public void testSumming() {
          assertEquals(3725, IntStreamEx.range(100).asDoubleStream().atLeast(50).collect(DoubleCollector.summing()), 0.0);
          assertEquals(3725, IntStreamEx.range(100).asDoubleStream().parallel().atLeast(50).collect(
              DoubleCollector.summing()), 0.0);
      }
  
      @Test
      public void testMin() {
          assertEquals(50, IntStreamEx.range(100).asDoubleStream().atLeast(50).collect(DoubleCollector.min())
                  .getAsDouble(), 0.0);
          assertEquals(50, IntStreamEx.range(100).asDoubleStream().atLeast(50).collect(
              DoubleCollector.min().andThen(OptionalDouble::getAsDouble)), 0.0);
          assertFalse(IntStreamEx.range(100).asDoubleStream().atLeast(200).collect(DoubleCollector.min()).isPresent());
      }
  
      @Test
      public void testMax() {
          assertEquals(99, IntStreamEx.range(100).asDoubleStream().atLeast(50).collect(DoubleCollector.max())
                  .getAsDouble(), 0.0);
          assertEquals(99, IntStreamEx.range(100).asDoubleStream().parallel().atLeast(50).collect(DoubleCollector.max())
                  .getAsDouble(), 0.0);
          assertFalse(IntStreamEx.range(100).asDoubleStream().atLeast(200).collect(DoubleCollector.max()).isPresent());
      }
  
      @Test
      public void testToArray() {
          assertArrayEquals(new double[] { 0, 1, 2, 3, 4 }, IntStreamEx.of(0, 1, 2, 3, 4).asDoubleStream().collect(
              DoubleCollector.toArray()), 0.0);
          assertArrayEquals(IntStreamEx.range(1000).asDoubleStream().toFloatArray(), IntStreamEx.range(1000).parallel()
                  .asDoubleStream().collect(DoubleCollector.toFloatArray()), 0.0f);
      }
  
      @Test
      public void testPartitioning() {
          double[] expectedEven = IntStream.range(0, 1000).asDoubleStream().map(i -> i * 2).toArray();
          double[] expectedOdd = IntStream.range(0, 1000).asDoubleStream().map(i -> i * 2 + 1).toArray();
          Map<Boolean, double[]> oddEven = IntStreamEx.range(2000).asDoubleStream().collect(
              DoubleCollector.partitioningBy(i -> i % 2 == 0));
          assertArrayEquals(expectedEven, oddEven.get(true), 0.0);
          assertArrayEquals(expectedOdd, oddEven.get(false), 0.0);
          oddEven = IntStreamEx.range(2000).asDoubleStream().parallel().collect(
              DoubleCollector.partitioningBy(i -> i % 2 == 0));
          assertArrayEquals(expectedEven, oddEven.get(true), 0.0);
          assertArrayEquals(expectedOdd, oddEven.get(false), 0.0);
      }
  
      @Test
      public void testGroupingBy() {
          Map<Double, double[]> collected = IntStreamEx.range(2000).asDoubleStream().collect(
              DoubleCollector.groupingBy(i -> i % 3));
          for (double i = 0; i < 3; i++) {
              double rem = i;
              assertArrayEquals(IntStream.range(0, 2000).asDoubleStream().filter(a -> a % 3 == rem).toArray(), collected
                      .get(i), 0.0);
          }
          collected = IntStreamEx.range(2000).asDoubleStream().parallel().collect(DoubleCollector.groupingBy(i -> i % 3));
          for (double i = 0; i < 3; i++) {
              double rem = i;
              assertArrayEquals(IntStream.range(0, 2000).asDoubleStream().filter(a -> a % 3 == rem).toArray(), collected
                      .get(i), 0.0);
          }
      }
  
      @Test
      public void testAsCollector() {
          assertEquals(499.5, IntStream.range(0, 1000).asDoubleStream().boxed().collect(DoubleCollector.summarizing())
                  .getAverage(), 0.000001);
          assertEquals(499.5, IntStream.range(0, 1000).parallel().asDoubleStream().boxed().collect(
              DoubleCollector.summarizing()).getAverage(), 0.000001);
      }
  
      @Test
      public void testAdaptor() {
          assertEquals(499.5, IntStreamEx.range(1000).asDoubleStream().collect(
              DoubleCollector.of(DoubleCollector.summarizing())).getAverage(), 0.000001);
          assertEquals(499.5, IntStreamEx.range(1000).parallel().asDoubleStream().collect(
              DoubleCollector.of(Collectors.summarizingDouble(Double::doubleValue))).getAverage(), 0.000001);
      }
  
      @Test
      public void testReducing() {
          assertEquals(7.0, DoubleStreamEx.of(1.0, 2.0, 3.5).collect(DoubleCollector.reducing(1.0, (a, b) -> a * b)), 0.0);
          assertEquals(7.0, DoubleStreamEx.of(1.0, 2.0, 3.5).parallel().collect(
              DoubleCollector.reducing(1.0, (a, b) -> a * b)), 0.0);
      }
  
      @Test
      public void testMapping() {
          assertEquals(10100.0, IntStreamEx.rangeClosed(0, 100).asDoubleStream().collect(
              DoubleCollector.mapping(x -> x * 2, DoubleCollector.summing())), 0.0);
  
          assertArrayEquals(LongStreamEx.of(1, 1, 2, 3).toArray(), DoubleStreamEx.of(0.8, 1.3, 1.7, 2.9).collect(
              DoubleCollector.mappingToObj(Math::round, LongCollector.toArray())));
      }
  
      @Test
      public void testAveraging() {
          assertFalse(DoubleStreamEx.empty().collect(DoubleCollector.averaging()).isPresent());
          assertEquals(1.0,
              DoubleStreamEx.of(0.0, 0.5, 1.0, 1.5, 2.0).collect(DoubleCollector.averaging()).getAsDouble(), 0.0);
      }
  
      @Test
      public void testToBooleanArray() {
          assertArrayEquals(new boolean[0], DoubleStreamEx.empty().collect(DoubleCollector.toBooleanArray(x -> true)));
          boolean[] expected = new boolean[] { true, false, false, true };
          assertArrayEquals(expected, DoubleStreamEx.of(1.0, 1.5, 2.7, 3.0).collect(
              DoubleCollector.toBooleanArray(x -> Math.floor(x) == x)));
          assertArrayEquals(expected, DoubleStreamEx.of(1.0, 1.5, 2.7, 3.0).parallel().collect(
              DoubleCollector.toBooleanArray(x -> Math.floor(x) == x)));
      }
  }
  