could postprocess Collect.gwt.xml to add <skip> lines for all the files that should be
            covered by testModule.gwt.xml. Maybe I'll try it someday.

            [*] https://code.google.com/p/google-web-toolkit/wiki/ResourceOracle#When_multiple_PathPrefix_es_have_the_same_path
                https://code.google.com/p/google-web-toolkit/issues/detail?id=7581

 * the beginning, thanks to using different `-source -target` values for compiling our `-jre` and
 * `-android` "flavors.")
 *
 * (We could consider releasing a listenablefuture:1.0.1 someday. But we would want to look into how
 * that affects users, especially users of the Android Gradle Plugin, since the plugin developers
 * put in a special hack for us: https://issuetracker.google.com/issues/131431257)
 */

    RuntimeExceptionThrowingFuture<String> input = new RuntimeExceptionThrowingFuture<>();
    /*
     * RuntimeExceptionThrowingFuture is provably not a ListenableFuture at compile time, so this
     * code may someday upset Error Prone. We want the test, though, in case that changes in the
     * future, so we will suppress any such future Error Prone reports.
     */
    assertWithMessage(

    RuntimeExceptionThrowingFuture<String> input = new RuntimeExceptionThrowingFuture<>();
    /*
     * RuntimeExceptionThrowingFuture is provably not a ListenableFuture at compile time, so this
     * code may someday upset Error Prone. We want the test, though, in case that changes in the
     * future, so we will suppress any such future Error Prone reports.
     */
    assertWithMessage(

 * the beginning, thanks to using different `-source -target` values for compiling our `-jre` and
 * `-android` "flavors.")
 *
 * (We could consider releasing a listenablefuture:1.0.1 someday. But we would want to look into how
 * that affects users, especially users of the Android Gradle Plugin, since the plugin developers
 * put in a special hack for us: https://issuetracker.google.com/issues/131431257)
 */

            return "cause=[Someday...]";
          }
        };
    AbstractFuture<Object> testFuture3 = new AbstractFuture<Object>() {};
    testFuture3.setFuture(testFuture2);
    assertThat(testFuture3.toString())
        .matches(
            "[^\\[]+\\[status=PENDING, setFuture=\\[[^\\[]+\\[status=PENDING,"
                + " info=\\[cause=\\[Someday...]]]]]");
    testFuture2.set("result string");

            return "cause=[Someday...]";
          }
        };
    AbstractFuture<Object> testFuture3 = new AbstractFuture<Object>() {};
    testFuture3.setFuture(testFuture2);
    assertThat(testFuture3.toString())
        .matches(
            "[^\\[]+\\[status=PENDING, setFuture=\\[[^\\[]+\\[status=PENDING,"
                + " info=\\[cause=\\[Someday...]]]]]");
    testFuture2.set("result string");