Error when compiling Typescript example from Docs

[tomitrescak]

I am trying the Typescript example from Docs

receive:

Type 'undefined' is not assignable to type ...

How to reproduce the issue:

tsconfig.json

{
  "compilerOptions": {
    "target": "esnext",
    "module": "commonjs",
    "moduleResolution": "node",
    "lib": ["es2017", "dom"],
    "jsx": "react",
    "baseUrl": "./src",
    "noEmit": true,
    "skipLibCheck": true,
    "pretty": true,
    "strict": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noImplicitReturns": true,
    "noFallthroughCasesInSwitch": true,
  }
}

Example from https://www.apollographql.com/docs/react/recipes/static-typing.html

import React from "react";
import gql from "graphql-tag";
import { graphql } from "react-apollo";

const HERO_QUERY = gql`
  query GetCharacter($episode: Episode!) {
    hero(episode: $episode) {
      name
      id
      friends {
        name
        id
        appearsIn
      }
    }
  }
`;

type Hero = {
  name: string;
  id: string;
  appearsIn: string[];
  friends: Hero[];
};

type Response = {
  hero: Hero;
};

type Variables = {
  episode: string;
};

// note the first parameter is empty here, we will exaplain that below
const withCharacter = graphql<{}, Response, Variables>(HERO_QUERY, {
  options: () => ({
    variables: { episode: "JEDI" }
  })
});

export default withCharacter(({ data: { loading, hero, error } }) => {
  if (loading) return <div>Loading</div>;
  if (error) return <h1>ERROR</h1>;
  return ...// actual component with data;
});

When disabling the strictNullChecks another error appears.

Version

• apollo-client@2.3.1

[hwillson]

If you're able to share a reproduction that outlines what you've tried, and what isn't working, that would definitely help with troubleshooting. That code sample isn't complete, so it's a bit difficult to pinpoint the problem you're encountering (e.g. return ... is invalid). I'll close this for now, but if you're able to share your code, let us know - thanks!