RangeUtilsTest.java

package com.kickstarter.libs.utils;

import com.kickstarter.libs.Range;

import junit.framework.TestCase;

import java.util.Arrays;
import java.util.Collections;
import java.util.List;

public final class RangeUtilsTest extends TestCase {

  public void testRanges() {
    final List<Integer> xs = Arrays.asList(1, 3, 4, 5, 6, 8, 10, 11);
    final List<Range> expected = Arrays.asList(
      Range.create(0, 1),
      Range.create(1, 4),
      Range.create(5, 1),
      Range.create(6, 2)
    );

    assertEquals(expected, RangeUtils.consecutiveRanges(xs));
  }

  public void testRanges_WithEmptyArray() {
    final List<Integer> xs = Collections.emptyList();
    final List<Range> expected = Collections.emptyList();

    assertEquals(expected, RangeUtils.consecutiveRanges(xs));
  }

  public void testRanges_WithRepeatedEntries() {
    final List<Integer> xs = Arrays.asList(1, 1, 1, 1);
    final List<Range> expected = Arrays.asList(
      Range.create(0, 4)
    );

    assertEquals(expected, RangeUtils.consecutiveRanges(xs));
  }

  public void testRanges_WithNonMonotonicArray() {
    final List<Integer> xs = Arrays.asList(1, 2, 1, 2, 1, 2);
    final List<Range> expected = Arrays.asList(
      Range.create(0, 2),
      Range.create(2, 2),
      Range.create(4, 2)
    );

    assertEquals(expected, RangeUtils.consecutiveRanges(xs));
  }

  public void testRanges_WithSingleton() {
    final List<Integer> xs = Arrays.asList(1);
    final List<Range> expected = Arrays.asList(
      Range.create(0, 1)
    );

    assertEquals(expected, RangeUtils.consecutiveRanges(xs));
  }
}