docs: @VisibleForTesting
      protected ProctorResult determineBucketsInternal(final Identifiers identifiers, final Map<String, Object> context, final Map<String, Integer> forcedGroups) {
          final Proctor proctor = proctorSource.get();
          if (proctor == null) {
              final Map<String, TestBucket> buckets = getDefaultBucketValues();
              final Map<String, Integer> versions = Maps.newHashMap();
              for (final String testName : buckets.keySet()) {
                  versions.put(testName, Integer.valueOf(-1));
              }
              return new ProctorResult(Audit.EMPTY_VERSION,
                      buckets,
                      Collections.<String, Allocation>emptyMap(),
                      Collections.<String, ConsumableTestDefinition>emptyMap()
              );
          }
          final ProctorResult result = proctor.determineTestGroups(identifiers, context, forcedGroups);
          return result;
      }