title: how to use enum in apollo-client?
body: <p>the enum define in <code>OrderTypesEnum.gql</code> </p>
  
  <pre><code>enum OrderTypes {
    full_buy
    pink_buy
  }
  </code></pre>
  
  <p>import OrderTypesEnum.gql file</p>
  
  <pre><code>import OrderTypes from '@/graphql/OrderTypesEnum.gql'`
  </code></pre>
  
  <p>but, How to get enum in code ?</p>
  
  <p>I use <code>OrderTypes.full_buy</code>  get some error: </p>
  
  <pre><code>   self.$apollo.mutate({
          mutation: createOrder,
          variables: {
            subjectId: self.subject.id,
            types: OrderTypes.full_buy
          }
        })
  </code></pre>
  
  <pre><code>Mutation createOrderMutation error: Invariant Violation: Schema type definitions not allowed in queries. Found: "EnumTypeDefinition"
  </code></pre>
  
  <p>the inspect of OrderTypes type enum </p>
  
  <p><a href="https://i.stack.imgur.com/WR2KF.png" rel="noreferrer"><img src="https://i.stack.imgur.com/WR2KF.png" alt="enter image description here"></a></p>