* Verifies that the {@code Set} returned by {@code nodes} has the expected mutability property
   * (see the {@code Graph} documentation for more information).
   */
  @Test
  public abstract void nodes_checkReturnedSetMutability();

  /**
   * Verifies that the {@code Set} returned by {@code adjacentNodes} has the expected mutability
   * property (see the {@code Graph} documentation for more information).
   */
  @Test

         * So this is probably just the "Windows Java 8" case. In that case, if we wanted *another*
         * layer of fallback before consulting the system property, we could try
         * com.sun.security.auth.module.NTSystem.
         *
         * But for now, we use the value from the system property as our best guess.
         */
        return fromSystemProperty;
      } catch (InvocationTargetException e) {

 *       tested in isolation.
 *   <li>The documentation style for testcases is to provide as javadoc a simple sentence or two
 *       describing the property that the testcase method purports to test. The javadocs do not say
 *       anything about how the property is tested. To find out, read the code.
 *   <li>These tests are "conformance tests", and do not attempt to test throughput, latency,

    Random r = new Random(0L);
    for (int i = 0; i < 1000000; i++) {
      int dividend = r.nextInt();
      int divisor = r.nextInt();
      // Test that the Euclidean property is preserved:
      assertThat(
              dividend
                  - (divisor * UnsignedInts.divide(dividend, divisor)
                      + UnsignedInts.remainder(dividend, divisor)))
          .isEqualTo(0);

  /**
   * Verifies that the {@code Set} returned by {@code nodes} has the expected mutability property
   * (see the {@code Network} documentation for more information).
   */
  @Test
  public abstract void nodes_checkReturnedSetMutability();

  /**
   * Verifies that the {@code Set} returned by {@code edges} has the expected mutability property
   * (see the {@code Network} documentation for more information).
   */
  @Test

  /**
   * Verifies that the {@code Set} returned by {@code nodes} has the expected mutability property
   * (see the {@code Network} documentation for more information).
   */
  @Test
  public abstract void nodes_checkReturnedSetMutability();

  /**
   * Verifies that the {@code Set} returned by {@code edges} has the expected mutability property
   * (see the {@code Network} documentation for more information).
   */
  @Test

 *       tested in isolation.
 *   <li>The documentation style for testcases is to provide as javadoc a simple sentence or two
 *       describing the property that the testcase method purports to test. The javadocs do not say
 *       anything about how the property is tested. To find out, read the code.
 *   <li>These tests are "conformance tests", and do not attempt to test throughput, latency,

    Random r = new Random(0L);
    for (int i = 0; i < 1000000; i++) {
      long dividend = r.nextLong();
      long divisor = r.nextLong();
      // Test that the Euclidean property is preserved:
      assertThat(
              dividend
                  - (divisor * UnsignedLongs.divide(dividend, divisor)
                      + UnsignedLongs.remainder(dividend, divisor)))
          .isEqualTo(0);

        .containsExactly(0.0, 1.0, 3.0, 6.0, 10.0, 15.0, 21.0)
        .inOrder();
  }

  public void testCopyOf_array_empty() {
    /*
     * We don't guarantee the same-as property, so we aren't obligated to test it. However, it's
     * useful in testing - when two things are the same then one can't have bugs the other doesn't.
     */
    assertThat(ImmutableDoubleArray.copyOf(new double[0]))

    Random r = new Random(0L);
    for (int i = 0; i < 1000000; i++) {
      int dividend = r.nextInt();
      int divisor = r.nextInt();
      // Test that the Euclidean property is preserved:
      assertThat(
              dividend
                  - (divisor * UnsignedInts.divide(dividend, divisor)
                      + UnsignedInts.remainder(dividend, divisor)))
          .isEqualTo(0);