}

    protected Stream<BuildStep> nonEmptyPredecessors(BuildStep step) {
        HashSet<BuildStep> preds = new HashSet<>();
        nonEmptyPredecessors(step, preds, new HashSet<>());
        return preds.stream();
    }

    private void nonEmptyPredecessors(BuildStep step, Set<BuildStep> preds, Set<BuildStep> visited) {

        }

        final DependencySet runtimeDependencies = runtimeConfiguration.getAllDependencies();
        final Set<String> packages = new HashSet<>();
        final Set<String> nodes = new HashSet<>();
        final Set<String> nodeIds = new HashSet<>();
        for (final Dependency dependency : runtimeDependencies) {
            final String id = dependency.getGroup() + ":" + dependency.getName();

        emptyIterator.remove();
    }

    /**
     * Test method for
     * {@link org.codelibs.core.collection.EmptyIterator#hasNext()}.
     */
    @Test
    public void testHasNext() {
        final EmptyIterator<String> emptyIterator = new EmptyIterator<String>();
        assertThat(emptyIterator.hasNext(), is(false));
    }

    /**
     * Test method for {@link org.codelibs.core.collection.EmptyIterator#next()}.
     */

        original_header_info = original_header_permalinks[header_no]

        if header_info["hashes"] != original_header_info["hashes"]:
            raise ValueError(
                "Header levels do not match between document and original document"
                f" (found {header_info['hashes']}, expected {original_header_info['hashes']})"
                f" for header №{header_no + 1} in line {header_info['line_no']}"
            )

import java.io.ObjectInputStream;
import java.io.Serializable;
import java.util.AbstractCollection;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Spliterator;
import java.util.Spliterators;
import org.jspecify.annotations.Nullable;

/**

    assertTrue(
        "non-empty multiset.entrySet() iterator.hasNext() returned false", iterator.hasNext());
    assertEquals(
        "multiset.entrySet() iterator.next() returned incorrect entry",
        Multisets.immutableEntry(e0(), 1),
        iterator.next());
    assertFalse(
        "size 1 multiset.entrySet() iterator.hasNext() returned true after next()",
        iterator.hasNext());
    iterator.remove();
    assertTrue(

    // known nonempty since we checked targets.size() > 1

    if (!thisIterator.hasNext()) {
      return false;
    }

    Object target = thatIterator.next();
    E current = thisIterator.next();
    try {
      while (true) {
        int cmp = unsafeCompare(current, target);

        if (cmp < 0) {
          if (!thisIterator.hasNext()) {
            return false;
          }

                        // advance res2
                        if (i2.hasNext()) {
                            res2 = i2.next();
                        } else {
                            done = true;
                        }
                    } else {
                        // advance res1
                        if (i1.hasNext()) {
                            res1 = i1.next();
                        } else {

  }

  /**
   * Implementation for the EntryIterator, which is used to build Key and Value iterators.
   *
   * <p>Expiration is only checked on hasNext(), so as to ensure that a next() call never returns
   * null when hasNext() has already been called.
   */
  private final class EntryIterator implements Iterator<Entry<K, V>> {
    final Iterator<Entry<K, Timestamped<V>>> iterator;

      stack.addLast(singletonIterator(checkNotNull(root)));
    }

    @Override
    public boolean hasNext() {
      return !stack.isEmpty();
    }

    @Override
    public T next() {
      Iterator<T> itr = stack.getLast(); // throws NSEE if empty
      T result = checkNotNull(itr.next());
      if (!itr.hasNext()) {
        stack.removeLast();
      }
      Iterator<T> childItr = children(result).iterator();