Mock resolveInfo param in graphql resolver

I created a helper function that will extract requested fields from a resolver,

module.exports = {
  Query: {
    users: (_, data, ctx, resolveInfo) => {
      const requestedFields = parseRequestedFields(resolveInfo);
      return UsersService.findById(userId, requestedFields);
    }
  }
}

I want to test parseRequestedFields() for that I need to create a fake resolveInfo.

How can I mock resolveInfo object here?

Update

This is the type definition of resolveInfo

type GraphQLResolveInfo = {
  fieldName: string,
  fieldNodes: Array<Field>,
  returnType: GraphQLOutputType,
  parentType: GraphQLCompositeType,
  schema: GraphQLSchema,
  fragments: { [fragmentName: string]: FragmentDefinition },
  rootValue: any,
  operation: OperationDefinition,
  variableValues: { [variableName: string]: any },
}