NullPointerException.class,
                () -> new FileSource((File) null),
                "Should fail, since you must specify a file");
        assertEquals("file cannot be null", e.getMessage());
    }

    @Test
    void testGetInputStream() throws Exception {
        File txtFile = new File("target/test-classes/source.txt");
        FileSource source = new FileSource(txtFile);

  /** Generator of new random hash codes */
  static final Random rng = new Random();

  /** Number of CPUS, to place bound on table size */
  static final int NCPU = Runtime.getRuntime().availableProcessors();

  /** Table of cells. When non-null, size is a power of 2. */
  @CheckForNull transient volatile Cell[] cells;

  /**

  }

  public void testBuilderPutAll() {
    Map<String, Integer> toPut = new LinkedHashMap<>();
    toPut.put("one", 1);
    toPut.put("two", 2);
    toPut.put("three", 3);
    Map<String, Integer> moreToPut = new LinkedHashMap<>();
    moreToPut.put("four", 4);
    moreToPut.put("five", 5);

    ImmutableBiMap<String, Integer> map =
        new Builder<String, Integer>().putAll(toPut).putAll(moreToPut).build();

                }
                return new Pair<>(groupList.stream().distinct().toArray(n1 -> new String[n1]),
                        roleList.stream().distinct().toArray(n2 -> new String[n2]));
            });
        } catch (final ExecutionException e) {
            logger.warn("Failed to process a group cache.", e);
            return new Pair<>(StringUtil.EMPTY_STRINGS, StringUtil.EMPTY_STRINGS);
        }

    StringWriter writer = new StringWriter();
    char[] buf = new char[64];
    int read;
    while ((read = reader.read(buf)) != -1) {
      writer.write(buf, 0, read);
    }
    reader.close();
    writer.close();

    assertExpectedString(writer.toString());
  }

  public void testCopyTo_appendable() throws IOException {
    StringBuilder builder = new StringBuilder();

    public static final File USER_MAVEN_CONFIGURATION_HOME = new File(USER_HOME, ".m2");

    public static final File DEFAULT_USER_SETTINGS_FILE = new File(USER_MAVEN_CONFIGURATION_HOME, "settings.xml");

    public static final File DEFAULT_PROJECT_SETTINGS_FILE = new File(".mvn", "settings.xml");

    public static final File DEFAULT_INSTALLATION_SETTINGS_FILE =
            new File(System.getProperty("maven.conf"), "settings.xml");

  @SuppressWarnings("JUnitIncompatibleType")
  public void testBuilder_withMutableEntry() {
    ImmutableMultimap.Builder<String, Integer> builder = new Builder<>();
    final StringHolder holder = new StringHolder();
    holder.string = "one";
    Entry<String, Integer> entry =
        new AbstractMapEntry<String, Integer>() {
          @Override
          public String getKey() {
            return holder.string;
          }

        StringBuffer sb = new StringBuffer();
        String n = this.name;

        // fix MSBROWSE name
        if ( n == null ) {
            n = "null";
        }
        else if ( n.charAt(0) == 0x01 ) {
            char c[] = n.toCharArray();
            c[ 0 ] = '.';
            c[ 1 ] = '.';
            c[ 14 ] = '.';
            n = new String(c);
        }

        #### Utility: compare with alternatives


        There is always *some* alternative to adding a new feature to Guava, even if it's just
        forking Guava yourself.


        We want to see that new features have some significant advantage over the alternatives.
        These advantages can take

    }

    public Throwable getRootCause() {
        return rootCause;
    }
    public String toString() {
        if( rootCause != null ) {
            StringWriter sw = new StringWriter();
            PrintWriter pw = new PrintWriter( sw );
            rootCause.printStackTrace( pw );
            return super.toString() + "\n" + sw;
        } else {
            return super.toString();
        }
    }