public void testFromPropertiesNullKey() {
    Properties properties =
        new Properties() {
          @Override
          public Enumeration<?> propertyNames() {
            return Iterators.asEnumeration(asList(null, "first", "second").iterator());
          }
        };
    properties.setProperty("first", "true");
    properties.setProperty("second", "null");

        return Equivalence.identity();
      }
    };

    abstract Equivalence<Object> defaultEquivalence();
  }

  /**
   * 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.
   */

   * through the returned deque.
   *
   * <p>It is imperative that the user manually synchronize on the returned deque when accessing any
   * of the deque's iterators:
   *
   * {@snippet :
   * Deque<E> deque = Queues.synchronizedDeque(Queues.newArrayDeque());
   * ...
   * deque.add(element);  // Needn't be in synchronized block
   * ...

 */

package com.google.common.collect;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkState;
import static com.google.common.collect.Iterators.emptyIterator;
import static com.google.common.collect.Sets.difference;
import static com.google.common.collect.Sets.intersection;
import static com.google.common.collect.Sets.newHashSet;

    private List<Multiset.Entry<E>> snapshot() {
      List<Multiset.Entry<E>> list = newArrayListWithExpectedSize(size());
      // Not Iterables.addAll(list, this), because that'll forward right back here.
      Iterators.addAll(list, iterator());
      return list;
    }
  }

  /**
   * @serialData the ConcurrentMap of elements and their counts.
   */

  open fun followUpDecision(
    call: Call,
    networkResponse: Response,
    nextRequest: Request?,
  ) {
  }

  /** Returns a new `EventListener` that publishes events to this and then `other`. */
  operator fun plus(other: EventListener): EventListener {
    val left =
      when {
        this === NONE -> return other
        this is AggregateEventListener -> this.eventListeners
        else -> arrayOf(this)
      }

    }

    @Override
    public boolean removeAll(Collection<?> c) {
      synchronized (mutex) {
        return Iterators.removeAll(delegate().iterator(), c);
      }
    }

    @Override
    public boolean retainAll(Collection<?> c) {
      synchronized (mutex) {
        return Iterators.retainAll(delegate().iterator(), c);
      }
    }

	}
	return r1, r2, scale, true
}

// registerShift parses an ARM/ARM64 shifted register reference and returns the encoded representation.
// There is known to be a register (current token) and a shift operator (peeked token).
func (p *Parser) registerShift(name string, prefix rune) int64 {
	if prefix != 0 {
		p.errorf("prefix %c not allowed for shifted register: $%s", prefix, name)
	}
	// R1 op R2 or r1 op constant.

 *
 * <p>The ordering of the row and column keys provided when the table is constructed determines the
 * iteration ordering across rows and columns in the table's views. None of the view iterators
 * support {@link Iterator#remove}. If the table is modified after an iterator is created, the
 * iterator remains valid.
 *
 * <p>This class requires less memory than the {@link HashBasedTable} and {@link TreeBasedTable}

* 🌐 Add Portuguese translation for `docs/pt/docs/tutorial/dependencies/dependencies-in-path-operation-operators.md`. PR [#11804](https://github.com/tiangolo/fastapi/pull/11804) by [@Joao-Pedro-P-Holanda](https://github.com/Joao-Pedro-P-Holanda).