public void aGrepResultsWithMultipleFiles() {
   GrepResults results =
       grep(
           constantExpression("ER"),
           on(Arrays.asList(localProfileWithWildecard("*"))),
           extraLinesAfter(20));
   for (GrepResult result : results) {
     if (result.getFileName().endsWith("gz")) {
       assertThat(
           StringUtils.contains(
               result.filterBy(regularExpression("E(.*)OR")).getText(), "GZ ERROR 1"),
           is(true));
       assertThat(
           StringUtils.contains(
               result.filterBy(regularExpression("E(.*)OR")).getText(), "GZ ERROR 2"),
           is(true));
     } else {
       assertThat(
           StringUtils.contains(
               result.filterBy(regularExpression("E(.*)OR")).getText(), "ERROR 1"),
           is(true));
       assertThat(
           StringUtils.contains(
               result.filterBy(regularExpression("E(.*)OR")).getText(), "ERROR 2"),
           is(true));
     }
   }
 }