code: public static Matcher enumDefinitionOfType(final String type) {
      return new Matcher() {
        @Override public boolean matches(Node node, NodeMetadata metadata) {
          JSType providedJsType = getJsType(metadata, type);
          if (providedJsType == null) {
            return false;
          }
          providedJsType = providedJsType.restrictByNotNullOrUndefined();
  
          JSType jsType = node.getJSType();
          return jsType != null && jsType.isEnumType() && providedJsType.isEquivalentTo(
              jsType.toMaybeEnumType().getElementsType().getPrimitiveType());
        }
      };
    }
docs: Returns a Matcher that matches definitions of an enum of the given type.