* retries, there is increased contention and reduced locality,
   * which is still better than alternatives.
   *
   * Per-thread hash codes are initialized to random values.
   * Contention and/or table collisions are indicated by failed
   * CASes when performing an update operation (see method
   * retryUpdate). Upon a collision, if the table size is less than
   * the capacity, it is doubled in size unless some other thread

}

// Borrowed from mutex_test.go
func HammerMutex(m *DRWMutex, loops int, cdone chan bool) {
	for range loops {
		m.Lock(id, source)
		m.Unlock(context.Background())
	}
	cdone <- true
}

// Borrowed from mutex_test.go
func TestMutex(t *testing.T) {
	loops := 200
	if testing.Short() {
		loops = 5
	}
	c := make(chan bool)
	m := NewDRWMutex(ds, "test")
	for range 10 {
		go HammerMutex(m, loops, c)

   * (inclusive) to {@code upper} (inclusive). (These are the same values contained in {@code
   * Range.closed(lower, upper)}.)
   *
   * @throws IllegalArgumentException if {@code lower} is greater than {@code upper}
   * @since 23.0
   */
  public static ContiguousSet<Integer> closed(int lower, int upper) {
    return create(Range.closed(lower, upper), DiscreteDomain.integers());
  }

  /**

package lock

import (
	"strings"
	"testing"
)

func TestFixLongPath(t *testing.T) {
	// 248 is long enough to trigger the longer-than-248 checks in
	// fixLongPath, but short enough not to make a path component
	// longer than 255, which is illegal on Windows. (which
	// doesn't really matter anyway, since this is purely a string
	// function we're testing, and it's not actually being used to

// globalGridStart is a channel that will block startup of grid connections until closed.
var globalGridStart = make(chan struct{})

// globalLockGridStart is a channel that will block startup of lock grid connections until closed.
var globalLockGridStart = make(chan struct{})

func initGlobalGrid(ctx context.Context, eps EndpointServerPools) error {
	hosts, local := eps.GridHosts()

    "input": "\uFFFD.com",
    "output": null
  },
  {
    "comment": "U+FFFD character encoded in Punycode",
    "input": "xn--zn7c.com",
    "output": null
  },
  {
    "comment": "Label longer than 63 code points",
    "input": "x01234567890123456789012345678901234567890123456789012345678901x",
    "output": "x01234567890123456789012345678901234567890123456789012345678901x"
  },
  {

        .isEqualTo("end index (2) must not be greater than size (1)");
  }

  public void testCheckPositionIndexes_reversed() {
    IndexOutOfBoundsException expected =
        assertThrows(IndexOutOfBoundsException.class, () -> checkPositionIndexes(1, 0, 1));
    assertThat(expected)
        .hasMessageThat()
        .isEqualTo("end index (0) must not be less than start index (1)");
  }

  @GwtIncompatible // Reflection

        .isEqualTo("end index (2) must not be greater than size (1)");
  }

  public void testCheckPositionIndexes_reversed() {
    IndexOutOfBoundsException expected =
        assertThrows(IndexOutOfBoundsException.class, () -> checkPositionIndexes(1, 0, 1));
    assertThat(expected)
        .hasMessageThat()
        .isEqualTo("end index (0) must not be less than start index (1)");
  }

  @GwtIncompatible // Reflection

        .test();
  }

  public void testRoundToDouble_twoToThe54PlusOne() {
    double twoToThe54 = Math.pow(2, 54);
    // the representable doubles are 2^54 and 2^54 + 4
    // 2^54+1 is less than halfway between, so HALF_DOWN and HALF_UP will both go down.
    new RoundToDoubleTester(BigDecimal.valueOf((1L << 54) + 1))
        .setExpectation(twoToThe54, DOWN, FLOOR, HALF_DOWN, HALF_UP, HALF_EVEN)

   * of values that will be added, if that knowledge is readily available. It is better to guess a
   * value slightly too high than slightly too low. If the value is not exact, the {@link
   * ImmutableDoubleArray} that is built will very likely occupy more memory than strictly
   * necessary; to trim memory usage, build using {@code builder.build().trimmed()}.
   */
  public static Builder builder(int initialCapacity) {