}
}

func TestSimpleWriteLockTimedOut(t *testing.T) {
	locked := testSimpleWriteLock(t, time.Second)

	expected := false
	if locked != expected {
		t.Errorf("TestSimpleWriteLockTimedOut(): \nexpected %#v\ngot      %#v", expected, locked)
	}
}

func testDualWriteLock(t *testing.T, duration time.Duration) (locked bool) {
	ctx := t.Context()
	lrwm := NewLRWMutex()

	lm.ref = 0
	lm.isWriteLock = false
}

// DRLocker returns a sync.Locker interface that implements
// the Lock and Unlock methods by calling drw.RLock and drw.RUnlock.
func (lm *LRWMutex) DRLocker() sync.Locker {
	return (*drlocker)(lm)
}

type drlocker LRWMutex

func (dr *drlocker) Lock()   { (*LRWMutex)(dr).RLock() }

 * stream was closed. Intended for use in a test where only a single stream should be opened and
 * possibly closed.
 *
 * @author Colin Decker
 */
@NullUnmarked
public interface TestStreamSupplier {

  /** Returns whether or not a new stream was opened. */
  boolean wasStreamOpened();

  /** Returns whether or not an open stream was closed. */

 * stream was closed. Intended for use in a test where only a single stream should be opened and
 * possibly closed.
 *
 * @author Colin Decker
 */
@NullUnmarked
public interface TestStreamSupplier {

  /** Returns whether or not a new stream was opened. */
  boolean wasStreamOpened();

  /** Returns whether or not an open stream was closed. */

import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;
import org.jspecify.annotations.NullUnmarked;

/**
 * A char source for testing that has configurable options.
 *
 * @author Colin Decker
 */
@NullUnmarked
public class TestCharSource extends CharSource implements TestStreamSupplier {

  private final TestByteSource byteSource;

  public TestCharSource(String content, TestOption... options) {

    // waiting for the slow interrupting thread to complete Thread.interrupt
    awaitBlockedOnInstanceOf(runner, InterruptibleTask.Blocker.class);

    Blocker blocker = (Blocker) LockSupport.getBlocker(runner);
    Thread owner = blocker.getOwner();
    assertThat(owner).isSameInstanceAs(interrupter);

    slowChannel.exitClose.countDown(); // release the interrupter

    // waiting for the slow interrupting thread to complete Thread.interrupt
    awaitBlockedOnInstanceOf(runner, InterruptibleTask.Blocker.class);

    Blocker blocker = (Blocker) LockSupport.getBlocker(runner);
    Thread owner = blocker.getOwner();
    assertThat(owner).isSameInstanceAs(interrupter);

    slowChannel.exitClose.countDown(); // release the interrupter

import static java.nio.charset.StandardCharsets.UTF_8;

import java.io.FilterWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
import org.jspecify.annotations.NullUnmarked;

/**
 * @author Colin Decker
 */
@NullUnmarked
public class TestWriter extends FilterWriter {

  private final TestOutputStream out;

  public TestWriter(TestOption... options) throws IOException {

import java.io.IOException;
import java.io.OutputStream;
import org.jspecify.annotations.NullUnmarked;

/**
 * A byte sink for testing that has configurable behavior.
 *
 * @author Colin Decker
 */
@NullUnmarked
public class TestByteSink extends ByteSink implements TestStreamSupplier {

  private final ByteArrayOutputStream bytes = new ByteArrayOutputStream();
  private final ImmutableSet<TestOption> options;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.Multimap;

/**
 * Helper methods/assertions for use with {@code com.google.common.collect} types.
 *
 * @author Colin Decker
 */
@GwtCompatible
final class GoogleHelpers {

  private GoogleHelpers() {}

  static void assertEmpty(Multimap<?, ?> multimap) {
    if (!multimap.isEmpty()) {