code: private static Map<String, Set<String>> expand(Map<String, Set<String>> viewToPropNames) {
  
          Set<String> baseProps = viewToPropNames.get(PropertyView.BASE_VIEW);
  
          if (baseProps == null) {
              baseProps = ImmutableSet.of();
          }
  
          if (!SquigglyConfig.isFilterImplicitlyIncludeBaseFieldsInView()) {
  
              // make an exception for full view
              Set<String> fullView = viewToPropNames.get(PropertyView.FULL_VIEW);
  
              if (fullView != null) {
                  fullView.addAll(baseProps);
              }
  
              return viewToPropNames;
          }
  
          for (Map.Entry<String, Set<String>> entry : viewToPropNames.entrySet()) {
              String viewName = entry.getKey();
              Set<String> propNames = entry.getValue();
  
              if (!PropertyView.BASE_VIEW.equals(viewName)) {
                  propNames.addAll(baseProps);
              }
          }
  
          return viewToPropNames;
      }
docs: apply the base fields to other views if configured to do so.