2.7.0 breaks existing typescript code

[cerrochoclo]

this code:

//file1.ts
import gql from 'graphql-tag';

export const someMutation = gql`someMutation`;

//file2.ts
import { ApolloClient } from 'apollo-client';
import {someMutation} from './file1.ts';

const apollo = new ApolloClient(...);
apollo.mutate({
      mutation: someMutation ,
      variables: {
//..
      }
    })

Those are the dependencies that work

@types\node@8.5.10
@types\node-fetch@1.6.7
apollo-cache-inmemory@1.1.7
apollo-client@2.2.2
apollo-link@1.0.7
apollo-link-context@1.0.3
apollo-link-http@1.3.2
graphql@0.11.7
graphql-tag@2.6.1
node-fetch@1.7.3
ts-node@4.1.0
typescript@2.7.1

but when updating to graphql-tag@2.7.0 we get and error:

error TS4023: Exported variable 'someMutation ' has or is using name 'DocumentNode' from external module "<my-project>node_modules/@types/graphql/language/ast" but cannot be named.
src/index.ts(38,3): error TS4053: Return type of public method from exported class has or is using name 'ExecutionResult' from external module "<my-project>/node_modules/@types/graphql/execution/execute" but cannot be named.

staying with 2.6.1 for now. Thanks!

[jnwng]

/cc @felixfbecker in case you have an idea as to what's going on here — im not super familiar with typescript but i'll try and repro.

i'll revert this change in an hour if i can't fix it.

[jnwng]

based on https://stackoverflow.com/questions/43335336/error-ts4058-return-type-of-exported-function-has-or-is-using-name-x-from-exter it looks like TypeScript users will have to explicitly import DocumentNode in their index.d.ts in order to use graphql-tag properly. @cerrochoclo can you confirm that that resolves at least the first error?

if this is the case, im going to revert this change since its a breaking API change or at least consider it in a major change

[jnwng]

reverted in 2.7.3 pending further investigation. see #141 for some context as to why this was added in the first place, but i think this might be a breaking change

[felixfbecker]

Yeah this is a known issue in TypeScript: microsoft/TypeScript#9944
The fix is to add an import { DocumentNode } from 'graphql' at the top of your file (maybe we should re-export that interface?). Not sure what you mean with index.d.ts though.

[jnwng]

ah, i see that would be helpful to know what the workflow change is here. if we re-export the interface within graphql-tag, will it mean that existing users won't see any breaking changes?

if existing users need to change their code, then we need to mark this with a major version change

[felixfbecker]

Tbh I don't know, I think it would still be required. But it would prevent another problem which is if you have multiple versions, there is no way for you to import the correct version of DocumentNode.

[cgatian]

I still wish this was a thing, even if it was breaking. 😄