Switch all files to TS syntax

Author: saihaj

.eslintrc.yml

@@ -509,7 +509,7 @@ overrides:
       '@typescript-eslint/consistent-indexed-object-style': off # TODO enable after TS conversion
       '@typescript-eslint/consistent-type-assertions':
         [error, { assertionStyle: as, objectLiteralTypeAssertions: never }]
-      '@typescript-eslint/consistent-type-definitions': off # TODO consider
+      '@typescript-eslint/consistent-type-definitions': error
       '@typescript-eslint/consistent-type-imports': off # TODO enable after TS conversion
       '@typescript-eslint/explicit-function-return-type': off # TODO consider
       '@typescript-eslint/explicit-member-accessibility': off # TODO consider

src/__testUtils__/dedent.ts

@@ -27,8 +27,8 @@ export function dedentString(string: string): string {
  * str === "{\n  test\n}";
  */
 export function dedent(
-  strings: $ReadOnlyArray<string>,
-  ...values: $ReadOnlyArray<string>
+  strings: ReadonlyArray<string>,
+  ...values: ReadonlyArray<string>
 ): string {
   let str = strings[0];
 

src/__tests__/starWarsData.ts

@@ -6,10 +6,10 @@
  * JSON objects in a more complex demo.
  */
 
-type Ship = {
-  id: string,
-  name: string,
-};
+interface Ship {
+  id: string;
+  name: string;
+}
 
 const allShips: Array<Ship> = [
   { id: '1', name: 'X-Wing' },
@@ -25,11 +25,11 @@ const allShips: Array<Ship> = [
   { id: '8', name: 'Executor' },
 ];
 
-type Faction = {
-  id: string,
-  name: string,
-  ships: Array<string>,
-};
+interface Faction {
+  id: string;
+  name: string;
+  ships: Array<string>;
+}
 
 const rebels: Faction = {
   id: '1',
@@ -59,11 +59,11 @@ export function createShip(shipName: string, factionId: string): Ship {
   return newShip;
 }
 
-export function getShip(id: string): Ship | void {
+export function getShip(id: string): Ship | undefined {
   return allShips.find((ship) => ship.id === id);
 }
 
-export function getFaction(id: string): Faction | void {
+export function getFaction(id: string): Faction | undefined {
   return allFactions.find((faction) => faction.id === id);
 }
 

src/connection/__tests__/connection-test.ts

@@ -55,6 +55,7 @@ const userType = new GraphQLObjectType({
 
 const { connectionType: friendConnection } = connectionDefinitions({
   name: 'Friend',
+  // @ts-expect-error
   nodeType: new GraphQLNonNull(userType),
   resolveNode: (edge) => allUsers[edge.node],
   edgeFields: () => ({
@@ -72,6 +73,7 @@ const { connectionType: friendConnection } = connectionDefinitions({
 });
 
 const { connectionType: userConnection } = connectionDefinitions({
+  // @ts-expect-error
   nodeType: new GraphQLNonNull(userType),
   resolveNode: (edge) => allUsers[edge.node],
 });

src/connection/arrayConnection.ts

@@ -6,18 +6,18 @@ import type {
   ConnectionCursor,
 } from './connection';
 
-type ArraySliceMetaInfo = {
-  sliceStart: number,
-  arrayLength: number,
-};
+interface ArraySliceMetaInfo {
+  sliceStart: number;
+  arrayLength: number;
+}
 
 /**
  * A simple function that accepts an array and connection arguments, and returns
  * a connection object for use in GraphQL. It uses array offsets as pagination,
  * so pagination will only work if the array is static.
  */
 export function connectionFromArray<T>(
-  data: $ReadOnlyArray<T>,
+  data: ReadonlyArray<T>,
   args: ConnectionArguments,
 ): Connection<T> {
   return connectionFromArraySlice(data, args, {
@@ -31,7 +31,7 @@ export function connectionFromArray<T>(
  * promised connection.
  */
 export function connectionFromPromisedArray<T>(
-  dataPromise: Promise<$ReadOnlyArray<T>>,
+  dataPromise: Promise<ReadonlyArray<T>>,
   args: ConnectionArguments,
 ): Promise<Connection<T>> {
   return dataPromise.then((data) => connectionFromArray(data, args));
@@ -47,7 +47,7 @@ export function connectionFromPromisedArray<T>(
  * total result large enough to cover the range specified in `args`.
  */
 export function connectionFromArraySlice<T>(
-  arraySlice: $ReadOnlyArray<T>,
+  arraySlice: ReadonlyArray<T>,
   args: ConnectionArguments,
   meta: ArraySliceMetaInfo,
 ): Connection<T> {
@@ -115,7 +115,7 @@ export function connectionFromArraySlice<T>(
  * and returns a promised connection.
  */
 export function connectionFromPromisedArraySlice<T>(
-  dataPromise: Promise<$ReadOnlyArray<T>>,
+  dataPromise: Promise<ReadonlyArray<T>>,
   args: ConnectionArguments,
   arrayInfo: ArraySliceMetaInfo,
 ): Promise<Connection<T>> {
@@ -144,7 +144,7 @@ export function cursorToOffset(cursor: ConnectionCursor): number {
  * Return the cursor associated with an object in an array.
  */
 export function cursorForObjectInConnection<T>(
-  data: $ReadOnlyArray<T>,
+  data: ReadonlyArray<T>,
   object: T,
 ): ConnectionCursor | null {
   const offset = data.indexOf(object);
@@ -160,7 +160,7 @@ export function cursorForObjectInConnection<T>(
  * otherwise it will be the default.
  */
 export function getOffsetWithDefault(
-  cursor: ConnectionCursor | null | void,
+  cursor: ConnectionCursor | null | undefined,
   defaultOffset: number,
 ): number {
   if (typeof cursor !== 'string') {

src/connection/connection.ts

@@ -67,31 +67,30 @@ export type ConnectionCursor = string;
 /**
  * A type describing the arguments a connection field receives in GraphQL.
  */
-export type ConnectionArguments = {
-  before?: ConnectionCursor | null,
-  after?: ConnectionCursor | null,
-  first?: number | null,
-  last?: number | null,
-  ...
-};
+export interface ConnectionArguments {
+  before?: ConnectionCursor | null;
+  after?: ConnectionCursor | null;
+  first?: number | null;
+  last?: number | null;
+}
 
-export type ConnectionConfig = {
-  name?: string,
-  nodeType: GraphQLNamedOutputType | GraphQLNonNull<GraphQLNamedOutputType>,
-  resolveNode?: GraphQLFieldResolver<any, any>,
-  resolveCursor?: GraphQLFieldResolver<any, any>,
-  edgeFields?: Thunk<GraphQLFieldConfigMap<any, any>>,
-  connectionFields?: Thunk<GraphQLFieldConfigMap<any, any>>,
-};
+export interface ConnectionConfig {
+  name?: string;
+  nodeType: GraphQLNamedOutputType | GraphQLNonNull<GraphQLNamedOutputType>;
+  resolveNode?: GraphQLFieldResolver<any, any>;
+  resolveCursor?: GraphQLFieldResolver<any, any>;
+  edgeFields?: Thunk<GraphQLFieldConfigMap<any, any>>;
+  connectionFields?: Thunk<GraphQLFieldConfigMap<any, any>>;
+}
 
-export type GraphQLConnectionDefinitions = {
-  edgeType: GraphQLObjectType,
-  connectionType: GraphQLObjectType,
-};
+export interface GraphQLConnectionDefinitions {
+  edgeType: GraphQLObjectType;
+  connectionType: GraphQLObjectType;
+}
 
 function resolveMaybeThunk<T>(thingOrThunk: Thunk<T>): T {
   return typeof thingOrThunk === 'function'
-    ? // $FlowFixMe[incompatible-use] - if it's a function, we assume a thunk without arguments
+    ? // @ts-expect-error - if it's a function, we assume a thunk without arguments
       thingOrThunk()
     : thingOrThunk;
 }
@@ -145,18 +144,18 @@ export function connectionDefinitions(
 /**
  * A type designed to be exposed as a `Connection` over GraphQL.
  */
-export type Connection<T> = {
-  edges: Array<Edge<T>>,
-  pageInfo: PageInfo,
-};
+export interface Connection<T> {
+  edges: Array<Edge<T>>;
+  pageInfo: PageInfo;
+}
 
 /**
  * A type designed to be exposed as a `Edge` over GraphQL.
  */
-export type Edge<T> = {
-  node: T,
-  cursor: ConnectionCursor,
-};
+export interface Edge<T> {
+  node: T;
+  cursor: ConnectionCursor;
+}
 
 /**
  * The common page info type used by all connections.
@@ -187,9 +186,9 @@ const pageInfoType = new GraphQLObjectType({
 /**
  * A type designed to be exposed as `PageInfo` over GraphQL.
  */
-export type PageInfo = {
-  startCursor: ConnectionCursor | null,
-  endCursor: ConnectionCursor | null,
-  hasPreviousPage: boolean,
-  hasNextPage: boolean,
-};
+export interface PageInfo {
+  startCursor: ConnectionCursor | null;
+  endCursor: ConnectionCursor | null;
+  hasPreviousPage: boolean;
+  hasNextPage: boolean;
+}

src/mutation/__tests__/mutation-test.ts

@@ -20,7 +20,7 @@ function dummyResolve() {
 }
 
 function wrapInSchema(mutationFields: {
-  [field: string]: GraphQLFieldConfig<any, any>,
+  [field: string]: GraphQLFieldConfig<any, any>;
 }): GraphQLSchema {
   const queryType = new GraphQLObjectType({
     name: 'Query',

src/mutation/mutation.ts

@@ -13,11 +13,11 @@ import type {
   Thunk,
 } from 'graphql';
 
-type MutationFn = (object: any, ctx: any, info: GraphQLResolveInfo) => mixed;
+type MutationFn = (object: any, ctx: any, info: GraphQLResolveInfo) => unknown;
 
 function resolveMaybeThunk<T>(thingOrThunk: Thunk<T>): T {
   return typeof thingOrThunk === 'function'
-    ? // $FlowFixMe[incompatible-use] - if it's a function, we assume a thunk without arguments
+    ? // @ts-expect-error - if it's a function, we assume a thunk without arguments
       thingOrThunk()
     : thingOrThunk;
 }
@@ -36,23 +36,23 @@ function resolveMaybeThunk<T>(thingOrThunk: Thunk<T>): T {
  * input field, and it should return an Object with a key for each
  * output field. It may return synchronously, or return a Promise.
  */
-type MutationConfig = {
-  name: string,
-  description?: string,
-  deprecationReason?: string,
-  extensions?: { [name: string]: mixed },
-  inputFields: Thunk<GraphQLInputFieldConfigMap>,
-  outputFields: Thunk<GraphQLFieldConfigMap<any, any>>,
-  mutateAndGetPayload: MutationFn,
-};
+interface MutationConfig {
+  name: string;
+  description?: string;
+  deprecationReason?: string;
+  extensions?: { [name: string]: unknown };
+  inputFields: Thunk<GraphQLInputFieldConfigMap>;
+  outputFields: Thunk<GraphQLFieldConfigMap<any, any>>;
+  mutateAndGetPayload: MutationFn;
+}
 
 /**
  * Returns a GraphQLFieldConfig for the mutation described by the
  * provided MutationConfig.
  */
 export function mutationWithClientMutationId(
   config: MutationConfig,
-): GraphQLFieldConfig<mixed, mixed> {
+): GraphQLFieldConfig<unknown, unknown> {
   const { name, inputFields, outputFields, mutateAndGetPayload } = config;
   const augmentedInputFields = () => ({
     ...resolveMaybeThunk(inputFields),
@@ -93,9 +93,9 @@ export function mutationWithClientMutationId(
       }
       return injectClientMutationId(payload);
 
-      function injectClientMutationId(data: mixed) {
+      function injectClientMutationId(data: unknown) {
         if (typeof data === 'object' && data !== null) {
-          // $FlowFixMe[cannot-write] It's bad idea to mutate data but we need to pass clientMutationId somehow. Maybe in future we figure out better solution satisfying all our test cases.
+          // @ts-expect-error FIXME It's bad idea to mutate data but we need to pass clientMutationId somehow. Maybe in future we figure out better solution satisfying all our test cases.
           data.clientMutationId = clientMutationId;
         }
 
@@ -107,10 +107,6 @@ export function mutationWithClientMutationId(
 
 // FIXME: Temporary until graphql-js resolves this issue
 // See, https://github.com/graphql/graphql-js/pull/3243#issuecomment-919510590
-declare function isPromiseLike(value: mixed): boolean %checks(value instanceof
-  Promise);
-
-// eslint-disable-next-line no-redeclare
-function isPromiseLike(value) {
+function isPromiseLike(value: any): value is Promise<unknown> {
   return typeof value?.then === 'function';
 }

src/node/__tests__/plural-test.ts

@@ -33,10 +33,7 @@ const queryType = new GraphQLObjectType({
       description: 'Map from a username to the user',
       inputType: GraphQLString,
       outputType: userType,
-      resolveSingleInput: (
-        username: string,
-        context: { lang: string, ... },
-      ) => ({
+      resolveSingleInput: (username: string, context: { lang: string }) => ({
         username,
         url: `www.facebook.com/${username}?lang=${context.lang}`,
       }),