ESLint: enable 'import/extensions' rule

.eslintrc.yml

@@ -168,7 +168,7 @@ rules:
   import/exports-last: off
   import/no-duplicates: error
   import/no-namespace: error
-  import/extensions: off # TODO [error, never] # TODO: switch to ignorePackages
+  import/extensions: [error, never] # TODO: switch to ignorePackages
   import/order: [error, { newlines-between: always-and-inside-groups }]
   import/newline-after-import: error
   import/prefer-default-export: off

src/__tests__/starWarsConnectionTests.js

@@ -4,7 +4,7 @@ import { expect } from 'chai';
 import { describe, it } from 'mocha';
 import { graphqlSync } from 'graphql';
 
-import { StarWarsSchema } from './starWarsSchema.js';
+import { StarWarsSchema } from './starWarsSchema';
 
 describe('Star Wars connections', () => {
   it('fetches the first ship of the rebels', () => {

src/__tests__/starWarsMutationTests.js

@@ -4,7 +4,7 @@ import { expect } from 'chai';
 import { describe, it } from 'mocha';
 import { graphqlSync } from 'graphql';
 
-import { StarWarsSchema } from './starWarsSchema.js';
+import { StarWarsSchema } from './starWarsSchema';
 
 describe('Star Wars mutations', () => {
   it('mutates the data set', () => {

src/__tests__/starWarsObjectIdentificationTests.js

@@ -4,7 +4,7 @@ import { expect } from 'chai';
 import { describe, it } from 'mocha';
 import { graphqlSync } from 'graphql';
 
-import { StarWarsSchema } from './starWarsSchema.js';
+import { StarWarsSchema } from './starWarsSchema';
 
 describe('Star Wars object identification', () => {
   it('fetches the ID and name of the rebels', () => {

src/__tests__/starWarsSchema.js

@@ -8,24 +8,24 @@ import {
   GraphQLString,
 } from 'graphql';
 
-import { nodeDefinitions, globalIdField, fromGlobalId } from '../node/node.js';
+import { nodeDefinitions, globalIdField, fromGlobalId } from '../node/node';
 
-import { connectionFromArray } from '../connection/arrayconnection.js';
+import { connectionFromArray } from '../connection/arrayconnection';
 
 import {
   connectionArgs,
   connectionDefinitions,
-} from '../connection/connection.js';
+} from '../connection/connection';
 
-import { mutationWithClientMutationId } from '../mutation/mutation.js';
+import { mutationWithClientMutationId } from '../mutation/mutation';
 
 import {
   getFaction,
   getShip,
   getRebels,
   getEmpire,
   createShip,
-} from './starWarsData.js';
+} from './starWarsData';
 
 /**
  * This is a basic end-to-end test, designed to demonstrate the various

src/connection/__tests__/connection.js

@@ -10,14 +10,14 @@ import {
   graphqlSync,
 } from 'graphql';
 
-import { connectionFromArray } from '../arrayconnection.js';
+import { connectionFromArray } from '../arrayconnection';
 
 import {
   backwardConnectionArgs,
   connectionArgs,
   connectionDefinitions,
   forwardConnectionArgs,
-} from '../connection.js';
+} from '../connection';
 
 const allUsers = [
   { name: 'Dan', friends: [1, 2, 3, 4] },

src/connection/arrayconnection.js

@@ -1,6 +1,6 @@
 // @flow strict
 
-import { base64, unbase64 } from '../utils/base64.js';
+import { base64, unbase64 } from '../utils/base64';
 
 import type {
   Connection,

src/index.js

@@ -7,15 +7,15 @@ export type {
   ConnectionCursor,
   Edge,
   PageInfo,
-} from './connection/connectiontypes.js';
+} from './connection/connectiontypes';
 
 // Helpers for creating connection types in the schema
 export {
   backwardConnectionArgs,
   connectionArgs,
   connectionDefinitions,
   forwardConnectionArgs,
-} from './connection/connection.js';
+} from './connection/connection';
 
 // Helpers for creating connections from arrays
 export {
@@ -27,16 +27,16 @@ export {
   cursorToOffset,
   getOffsetWithDefault,
   offsetToCursor,
-} from './connection/arrayconnection.js';
+} from './connection/arrayconnection';
 
 // Helper for creating mutations with client mutation IDs
-export { mutationWithClientMutationId } from './mutation/mutation.js';
+export { mutationWithClientMutationId } from './mutation/mutation';
 
 // Helper for creating node definitions
-export { nodeDefinitions } from './node/node.js';
+export { nodeDefinitions } from './node/node';
 
 // Helper for creating plural identifying root fields
-export { pluralIdentifyingRootField } from './node/plural.js';
+export { pluralIdentifyingRootField } from './node/plural';
 
 // Utilities for creating global IDs in systems that don't have them.
-export { fromGlobalId, globalIdField, toGlobalId } from './node/node.js';
+export { fromGlobalId, globalIdField, toGlobalId } from './node/node';

src/node/node.js

@@ -13,7 +13,7 @@ import type {
   GraphQLTypeResolver,
 } from 'graphql';
 
-import { base64, unbase64 } from '../utils/base64.js';
+import { base64, unbase64 } from '../utils/base64';
 
 type GraphQLNodeDefinitions<TContext> = {|
   nodeInterface: GraphQLInterfaceType,