Each file is a list of API features, one per line.

go1.txt (and similarly named files) are frozen once a version has been
shipped. Each file adds new lines but does not remove any.

except.txt lists features that may disappear without breaking true
compatibility.

Starting with go1.19.txt, each API feature line must end in "#nnnnn"
giving the GitHub issue number of the proposal issue that accepted

        type: choice
        options:
          - translate-page
          - translate-lang
          - update-outdated
          - add-missing
          - update-and-add
          - remove-all-removable
      language:
        description: Language to translate to as a letter code (e.g. "es" for Spanish)
        type: string
        required: false
        default: ""
      en_path:

  }

  private static Set<Feature<?>> computeReserializedMapFeatures(Set<Feature<?>> mapFeatures) {
    Set<Feature<?>> derivedFeatures = copyToSet(mapFeatures);
    derivedFeatures.remove(CollectionFeature.SERIALIZABLE);
    derivedFeatures.remove(CollectionFeature.SERIALIZABLE_INCLUDING_VIEWS);
    return derivedFeatures;
  }

  private static Set<Feature<?>> computeEntrySetFeatures(Set<Feature<?>> mapFeatures) {

    taskFaker.runNextTask()
    assertThat(cache.remove("a")).isTrue()
    assertAbsent("a")
    cache.close()
    createNewCache()

    // The journal will have no record that 'a' was removed. It will have an entry for 'a', but when
    // it tries to read the cache files, it will find they were deleted. Once it encounters an entry
    // with missing cache files, it should remove it from the cache entirely.

   *
   * @param o element to be removed from this queue, if present
   * @return {@code true} if this queue changed as a result of the call
   */
  @CanIgnoreReturnValue // pushed down from class to method
  @Override
  public boolean remove(@Nullable Object o) {
    Monitor monitor = this.monitor;
    monitor.enter();
    try {
      return q.remove(o);
    } finally {
      monitor.leave();
    }

    Multimap<String, Integer> map = create();
    map.put("bar", 1);
    map.put("foo", 2);
    map.put("bar", 3);
    map.put("bar", 4);
    assertEquals("[bar, foo]", map.keySet().toString());
    map.keySet().remove("bar");
    assertEquals("{foo=[2]}", map.toString());
  }

  public void testLinkedKeys() {
    Multimap<String, Integer> map = create();
    map.put("bar", 1);
    map.put("foo", 2);

    }
  }

  @CanIgnoreReturnValue
  @Override
  public @Nullable V remove(@Nullable Object key) {
    if (key == null) {
      return null;
    }
    int hash = hash(key);
    return segmentFor(hash).remove(key, hash);
  }

  @CanIgnoreReturnValue
  @Override
  public boolean remove(@Nullable Object key, @Nullable Object value) {
    if (key == null || value == null) {

        ubToAdd = rangeBelowUb.upperBound;
      }
    }

    // Remove ranges which are strictly enclosed.
    rangesByLowerBound.subMap(lbToAdd, ubToAdd).clear();

    replaceRangeWithSameLowerBound(Range.create(lbToAdd, ubToAdd));
  }

  @Override
  public void remove(Range<C> rangeToRemove) {
    checkNotNull(rangeToRemove);

    if (rangeToRemove.isEmpty()) {
      return;

  /** Removes all associations from this range map (optional operation). */
  void clear();

  /**
   * Removes all associations from this range map in the specified range (optional operation).
   *
   * <p>If {@code !range.contains(k)}, {@link #get(Comparable) get(k)} will return the same result
   * before and after a call to {@code remove(range)}. If {@code range.contains(k)}, then after a

  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testRemovePropagatesToMultimap() {
    assertTrue(multimap().entries().remove(mapEntry(k0(), v0())));
    expectMissing(mapEntry(k0(), v0()));
    assertEquals(getNumElements() - 1, multimap().size());
    assertFalse(multimap().containsEntry(k0(), v0()));
  }