return 1;
          }
        };

    builder.put(entry);
    holder.string = "two";
    assertMapEquals(builder.buildOrThrow(), "one", 1);
  }

  public void testBuilderPutAllWithEmptyMap() {
    ImmutableMap<String, Integer> map =
        new Builder<String, Integer>()
            .putAll(Collections.<String, Integer>emptyMap())
            .buildOrThrow();