sink.writeFrom(in);
    assertFalse(in.closed());
  }

  public void testClosesOnErrors_copyingFromByteSourceThatThrows() {
    for (TestOption option : EnumSet.of(OPEN_THROWS, READ_THROWS, CLOSE_THROWS)) {
      TestByteSource failSource = new TestByteSource(new byte[10], option);
      TestByteSink okSink = new TestByteSink();
      assertThrows(IOException.class, () -> failSource.copyTo(okSink));

      public void handlePotentialDeadlock(PotentialDeadlockException e) {
        logger.get().log(Level.SEVERE, "Detected potential deadlock", e);
      }
    },

    /**
     * Disables cycle detection. This option causes the factory to return unmodified lock
     * implementations provided by the JDK, and is provided to allow applications to easily
     * parameterize when cycle detection is enabled.
     *

   *
   * <p><b>{@code Stream} equivalent:</b> {@code stream.filter(type::isInstance).map(type::cast)}.
   * This does perform a little more work than necessary, so another option is to insert an
   * unchecked cast at some later point:
   *
   * <pre>
   * {@code @SuppressWarnings("unchecked") // safe because of ::isInstance check
   * ImmutableList<NewType> result =

      description: If this issue is platform-specific, then please select the relevant platforms.
      multiple: true
      options:
        - Android
        - GWT
        - Java 8
        - Java 11
        - Java 17

  - type: checkboxes
    attributes:
      label: Checklist
      options:
        - label: >
            I agree to follow the

    assertFalse(out.closed());
  }

  public void testClosesOnErrors_copyingToByteSinkThatThrows() {
    for (TestOption option : EnumSet.of(OPEN_THROWS, WRITE_THROWS, CLOSE_THROWS)) {
      TestByteSource okSource = new TestByteSource(bytes);
      assertThrows(IOException.class, () -> okSource.copyTo(new TestByteSink(option)));
      // ensure stream was closed IF it was opened (depends on implementation whether or not it's

      description: Please provide use cases that actually came up in the real world.
    validations:
      required: true

  - type: checkboxes
    attributes:
      label: Checklist
      options:
        - label: >
            I agree to follow the
            [code of conduct](https://github.com/google/.github/blob/master/CODE_OF_CONDUCT.md).
          required: true
        - label: >

    return new JdkPatternCompiler();
  }

  private static void logPatternCompilerError(ServiceConfigurationError e) {
    logger.log(Level.WARNING, "Error loading regex compiler, falling back to next option", e);
  }

  private static final class JdkPatternCompiler implements PatternCompiler {
    @Override
    public CommonPattern compile(String pattern) {
      return new JdkPattern(Pattern.compile(pattern));
    }

     * StackOverflowError: We can't reliably call setException(error).
     *
     * - Any kind of Error from a listener. Even if we could distinguish that case (by exposing some
     * extra state from AbstractFuture), our options are limited: A call to setException() would be
     * a no-op. We could log, but if that's what we really want, we should modify
     * AbstractFuture.executeListener to do so, since that method would have the ability to continue

 * href="http://en.wikipedia.org/wiki/Null_Object_pattern">null object</a> for the type in question.
 *
 * <p>This class is not intended as a direct analogue of any existing "option" or "maybe" construct
 * from other programming environments, though it may bear some similarities.
 *
 * <p>An instance of this class is serializable if its reference is absent or is a serializable
 * object.
 *

    // transformEntries(map1, transformer);
    // transformEntries(map4, transformer);
    // transformEntries(map7, transformer);
  }

  public void testTransformEntriesExample() {
    Map<String, Boolean> options = ImmutableMap.of("verbose", true, "sort", false);
    EntryTransformer<String, Boolean, String> flagPrefixer =
        new EntryTransformer<String, Boolean, String>() {
          @Override