docs: public static Matcher<PrintableResult> hasSingleFailureMatching(final Matcher<Throwable> matcher) {
          return new TypeSafeMatcher<PrintableResult>() {
              @Override
              public boolean matchesSafely(PrintableResult item) {
                  return item.failureCount() == 1 && matcher.matches(item.failures().get(0).getException());
              }
  
              public void describeTo(Description description) {
                  description.appendText("has failure with exception matching ");
                  matcher.describeTo(description);
              }
          };
      }