refactor: use stricter typescript

benchmark/start-server.ts

@@ -44,7 +44,7 @@ const yogaMap: Record<string, RequestListener> = {
     parserAndValidationCache: false,
     graphqlEndpoint: '/graphql-no-parse-validate-cache',
   }),
-  '/ping': (req, res) => {
+  '/ping': (_, res) => {
     res.writeHead(200);
     res.end();
   },

package.json

@@ -34,6 +34,7 @@
     "build-website": "pnpm build && cd website && pnpm build",
     "changeset": "changeset",
     "check": "pnpm -r run check",
+    "check:types": "tsc --pretty --noEmit",
     "lint": "cross-env \"ESLINT_USE_FLAT_CONFIG=false\" eslint --ext ts,js,tsx,jsx .",
     "postchangeset": "pnpm install --no-frozen-lockfile",
     "postinstall": "husky install",
@@ -58,8 +59,10 @@
     "@changesets/cli": "2.27.10",
     "@theguild/eslint-config": "0.13.2",
     "@theguild/prettier-config": "3.0.0",
+    "@tsconfig/strictest": "^2.0.5",
     "@types/babel__core": "7.20.5",
     "@types/babel__preset-env": "7.9.7",
+    "@types/html-minifier-terser": "^7.0.2",
     "@types/jest": "29.5.14",
     "@types/supertest": "6.0.2",
     "@typescript-eslint/eslint-plugin": "^8.18.0",

packages/client/apollo-link/__integration-tests__/apollo-link.spec.ts

@@ -95,7 +95,7 @@ describe('Yoga Apollo Link', () => {
     let i = 0;
     await new Promise<void>(resolve => {
       const subscription = observable.subscribe((result: FetchResult) => {
-        collectedValues.push(result.data?.time);
+        collectedValues.push(result.data?.['time']);
         i++;
         if (i > 2) {
           subscription.unsubscribe();

packages/graphiql/src/YogaGraphiQL.tsx

@@ -133,7 +133,7 @@ export function YogaGraphiQL(props: YogaGraphiQLProps): React.ReactElement {
     false,
   );
 
-  const [query, setQuery] = useState(params.query?.toString());
+  const [query, setQuery] = useState(params['query']?.toString());
   const explorer = explorerPlugin({
     showAttribution: true,
   });

packages/graphiql/vite.config.ts

@@ -21,7 +21,7 @@ export default defineConfig({
   },
   define:
     // Having this environment variable set in development will break the dev server
-    process.env.BUILD === 'true'
+    process.env['BUILD'] === 'true'
       ? {
           'process.env.NODE_ENV': '"production"',
         }

packages/graphql-yoga/__integration-tests__/browser.spec.ts

@@ -73,7 +73,7 @@ export function createTestSchema() {
             },
           },
           type: GraphQLString,
-          resolve: (_root, args) => args.text,
+          resolve: (_root, args) => args['text'],
         },
         hello: {
           type: GraphQLString,
@@ -111,7 +111,7 @@ export function createTestSchema() {
           },
           type: GraphQLInt,
           resolve: (_root, args) => {
-            return args.number;
+            return args['number'];
           },
         },
       }),
@@ -186,7 +186,7 @@ export function createTestSchema() {
             },
           },
           async *subscribe(_root, args) {
-            for (let count = 1; count <= args.to; count++) {
+            for (let count = 1; count <= args['to']; count++) {
               yield { count };
               await setTimeout$(200);
             }
@@ -231,7 +231,7 @@ describe('browser', () => {
     await new Promise<void>(resolve => server.listen(0, resolve));
     port = (server.address() as AddressInfo).port;
     browser = await chromium.launch({
-      headless: process.env.PLAYWRIGHT_HEADLESS !== 'false',
+      headless: process.env['PLAYWRIGHT_HEADLESS'] !== 'false',
       args: ['--incognito', '--no-sandbox', '--disable-setuid-sandbox'],
     });
   });

packages/graphql-yoga/__integration-tests__/file-uploads.spec.ts

@@ -12,11 +12,11 @@ describe('file uploads', () => {
     schema: createSchema({
       resolvers: {
         Mutation: {
-          arrayBuffer: async (root, args) => {
+          arrayBuffer: async (_, args) => {
             const buf = Buffer.from(await args.file.arrayBuffer());
             return sourceFile.equals(buf);
           },
-          stream: async (root, args) => {
+          stream: async (_, args) => {
             const chunks = [];
             for await (const chunk of args.file.stream()) {
               chunks.push(chunk);

packages/graphql-yoga/__integration-tests__/node-http.spec.ts

@@ -267,7 +267,7 @@ describe('node-http', () => {
       expect(body).toHaveLength(3);
       for (const result of body) {
         expect(result.errors).toBeUndefined();
-        expect(result.data?.isNode).toBe(true);
+        expect(result.data?.['isNode']).toBe(true);
       }
     } finally {
       await new Promise<void>(resolve => server.close(() => resolve()));

packages/graphql-yoga/__tests__/batching.spec.ts

@@ -331,7 +331,7 @@ describe('Batching', () => {
 
     expect(contexts.length).toEqual(2);
     expect(contexts[0]).not.toBe(contexts[1]);
-    expect(contexts[0].i).toEqual(1);
-    expect(contexts[1].i).toEqual(2);
+    expect(contexts[0]!.i).toEqual(1);
+    expect(contexts[1]!.i).toEqual(2);
   });
 });

packages/graphql-yoga/__tests__/error-masking.spec.ts

@@ -111,10 +111,10 @@ describe('error masking', () => {
   });
 
   it('includes the original error in the extensions in dev mode (process.env.NODE_ENV=development)', async () => {
-    const initialEnv = process.env.NODE_ENV;
+    const initialEnv = process.env['NODE_ENV'];
 
     try {
-      process.env.NODE_ENV = 'development';
+      process.env['NODE_ENV'] = 'development';
 
       const yoga = createYoga({
         schema: createTestSchema(),
@@ -137,7 +137,7 @@ describe('error masking', () => {
         'Error: This error will get mask if you enable maskedError.',
       );
     } finally {
-      process.env.NODE_ENV = initialEnv;
+      process.env['NODE_ENV'] = initialEnv;
     }
   });
 

packages/graphql-yoga/__tests__/http-extensions.spec.ts

@@ -631,7 +631,9 @@ describe('Result Extensions', () => {
         this.name = 'CustomError';
       }
 
-      toJSON() {
+      // eslint-disable-next-line
+      // @ts-ignore - Only in graphql@^16 is `toJSON` a base method
+      /* override */ toJSON() {
         return {
           message: this.message,
           extensions: { name: this.name, foo: 'bar' },

packages/graphql-yoga/__tests__/logging.spec.ts

@@ -28,17 +28,17 @@ describe('logging', () => {
       expect(console.debug).not.toHaveBeenCalled();
     });
     it(`prints debug messages if DEBUG env var is set`, () => {
-      const originalValue = process.env.DEBUG;
+      const originalValue = process.env['DEBUG'];
       try {
-        process.env.DEBUG = '1';
+        process.env['DEBUG'] = '1';
 
         jest.spyOn(console, 'debug').mockImplementationOnce(() => {});
         const logger = createLogger();
         logger.debug('TEST');
 
         expect(console.debug).toHaveBeenCalled();
       } finally {
-        process.env.DEBUG = originalValue;
+        process.env['DEBUG'] = originalValue;
       }
     });
   });

packages/graphql-yoga/__tests__/recipes.spec.ts

@@ -12,7 +12,7 @@ describe('recipe', () => {
         resolvers: {
           Query: {
             id: (_, __, context: YogaInitialContext) => {
-              return context.params.extensions?.id;
+              return context.params.extensions?.['id'];
             },
           },
         },

packages/graphql-yoga/__tests__/request-cancellation.spec.ts

@@ -6,7 +6,7 @@ import { useExecutionCancellation } from '../src/plugins/use-execution-cancellat
 
 const variants: Array<[name: string, fetchAPI: undefined | FetchAPI]> = [['Ponyfill', undefined]];
 
-if (!process.env.LEAK_TESTS) {
+if (!process.env['LEAK_TESTS']) {
   variants.push([
     'Native',
     // eslint-disable-next-line @typescript-eslint/ban-ts-comment

packages/graphql-yoga/__tests__/requests.spec.ts

@@ -19,7 +19,7 @@ describe('requests', () => {
         requestUrl: (_, __, ctx) => ctx.request.url,
       },
       Mutation: {
-        echo(root, args) {
+        echo(_, args) {
           return args.str;
         },
       },
@@ -534,7 +534,7 @@ describe('requests', () => {
     const firstResBody = await firstRes.json();
     expect(firstResBody.data.greetings).toBe('Hello world!');
     expect(onExecuteFn).toHaveBeenCalledTimes(1);
-    expect(onExecuteFn.mock.calls[0][0].args.contextValue.request).toBe(firstReq);
+    expect(onExecuteFn.mock.calls[0]?.[0].args.contextValue.request).toBe(firstReq);
     const secondReq = new Request('http://yoga/graphql', {
       method: 'POST',
       headers: {
@@ -547,9 +547,9 @@ describe('requests', () => {
     const secondResBody = await secondRes.json();
     expect(secondResBody.data.greetings).toBe('Hello world!');
     expect(onExecuteFn).toHaveBeenCalledTimes(2);
-    expect(onExecuteFn.mock.calls[1][0].args.contextValue.request).toBe(secondReq);
-    expect(onExecuteFn.mock.calls[1][0].args.contextValue).not.toBe(
-      onExecuteFn.mock.calls[0][0].args.contextValue,
+    expect(onExecuteFn.mock.calls[1]?.[0].args.contextValue.request).toBe(secondReq);
+    expect(onExecuteFn.mock.calls[1]?.[0].args.contextValue).not.toBe(
+      onExecuteFn.mock.calls[0]![0].args.contextValue,
     );
   });
 });

packages/graphql-yoga/scripts/generate-graphiql-html.js

@@ -5,16 +5,26 @@ import { minify as minifyT } from 'html-minifier-terser';
 
 const __dirname = path.dirname(fileURLToPath(import.meta.url));
 
+// TODO review if this function is still needed.
+// The types suggest that minifyT is already returning a string.
+// And toString does not accept an argument.
+/**
+ * @param {string} str
+ */
 async function minify(str) {
   return (
-    await minifyT(str, {
-      minifyJS: true,
-      useShortDoctype: false,
-      removeAttributeQuotes: true,
-      collapseWhitespace: true,
-      minifyCSS: true,
-    })
-  ).toString('utf-8');
+    (
+      await minifyT(str, {
+        minifyJS: true,
+        useShortDoctype: false,
+        removeAttributeQuotes: true,
+        collapseWhitespace: true,
+        minifyCSS: true,
+      })
+    )
+      // @ts-expect-error
+      .toString('utf-8')
+  );
 }
 
 async function minifyGraphiQLHTML() {

packages/graphql-yoga/src/error.ts

@@ -41,7 +41,7 @@ export function isAbortError(error: unknown): error is DOMException {
   return (
     typeof error === 'object' &&
     error?.constructor?.name === 'DOMException' &&
-    (error as Record<string, unknown>).name === 'AbortError'
+    (error as DOMException).name === 'AbortError'
   );
 }
 
@@ -135,17 +135,20 @@ export function getResponseInitByRespectingErrors(
 
   if ('errors' in result && result.errors?.length) {
     for (const error of result.errors) {
-      if (error.extensions?.http) {
-        if (error.extensions.http.headers) {
-          Object.assign(headers, error.extensions.http.headers);
+      if (error.extensions?.['http']) {
+        if (error.extensions['http'].headers) {
+          Object.assign(headers, error.extensions['http'].headers);
         }
-        if (isApplicationJson && error.extensions.http.spec) {
+        if (isApplicationJson && error.extensions['http'].spec) {
           continue;
         }
-        if (error.extensions.http.status && (!status || error.extensions.http.status > status)) {
-          status = error.extensions.http.status;
+        if (
+          error.extensions['http'].status &&
+          (!status || error.extensions['http'].status > status)
+        ) {
+          status = error.extensions['http'].status;
         }
-      } else if (!isOriginalGraphQLError(error) || error.extensions?.unexpected) {
+      } else if (!isOriginalGraphQLError(error) || error.extensions?.['unexpected']) {
         unexpectedErrorExists = true;
       }
     }

packages/graphql-yoga/src/index.ts

@@ -39,4 +39,7 @@ export {
 } from '@envelop/core';
 export { getSSEProcessor } from './plugins/result-processor/sse.js';
 export { useExecutionCancellation } from './plugins/use-execution-cancellation.js';
-export { LandingPageRenderer, LandingPageRendererOpts } from './plugins/use-unhandled-route.js';
+export {
+  type LandingPageRenderer,
+  type LandingPageRendererOpts,
+} from './plugins/use-unhandled-route.js';

packages/graphql-yoga/src/plugins/request-parser/post-json.ts

@@ -23,7 +23,7 @@ export async function parsePOSTJsonRequest(request: Request): Promise<GraphQLPar
       },
     };
     if (err instanceof Error) {
-      extensions.originalError = {
+      extensions['originalError'] = {
         name: err.name,
         message: err.message,
       };

packages/graphql-yoga/src/plugins/request-parser/post-multipart.ts

@@ -58,7 +58,7 @@ export async function parsePOSTMultipartRequest(request: Request): Promise<Graph
     }
     for (const fileIndex in map) {
       const file = requestBody.get(fileIndex);
-      const keys = map[fileIndex];
+      const keys = map[fileIndex]!;
       for (const key of keys) {
         dset(operations, key, file);
       }

packages/graphql-yoga/src/plugins/request-validation/use-check-graphql-query-params.ts

@@ -59,7 +59,7 @@ export function checkGraphQLQueryParams(
 
   assertInvalidParams(params, extraParamNames);
 
-  if (params.query == null) {
+  if (params['query'] == null) {
     throw createGraphQLError('Must provide query string.', {
       extensions: {
         http: {
@@ -73,7 +73,7 @@ export function checkGraphQLQueryParams(
     });
   }
 
-  const queryType = extendedTypeof(params.query);
+  const queryType = extendedTypeof(params['query']);
   if (queryType !== 'string') {
     throw createGraphQLError(`Expected "query" param to be a string, but given ${queryType}.`, {
       extensions: {
@@ -87,7 +87,7 @@ export function checkGraphQLQueryParams(
     });
   }
 
-  const variablesParamType = extendedTypeof(params.variables);
+  const variablesParamType = extendedTypeof(params['variables']);
   if (!['object', 'null', 'undefined'].includes(variablesParamType)) {
     throw createGraphQLError(
       `Expected "variables" param to be empty or an object, but given ${variablesParamType}.`,
@@ -104,7 +104,7 @@ export function checkGraphQLQueryParams(
     );
   }
 
-  const extensionsParamType = extendedTypeof(params.extensions);
+  const extensionsParamType = extendedTypeof(params['extensions']);
   if (!['object', 'null', 'undefined'].includes(extensionsParamType)) {
     throw createGraphQLError(
       `Expected "extensions" param to be empty or an object, but given ${extensionsParamType}.`,

packages/graphql-yoga/src/plugins/request-validation/use-prevent-mutation-via-get.ts

@@ -59,7 +59,7 @@ export function usePreventMutationViaGET(): Plugin<YogaInitialContext> {
 
         if (result instanceof Error) {
           if (result instanceof GraphQLError) {
-            result.extensions.http = {
+            result.extensions['http'] = {
               spec: true,
               status: 400,
             };

packages/graphql-yoga/src/plugins/result-processor/accept.ts

@@ -6,6 +6,8 @@ export function getMediaTypesForRequestInOrder(request: Request): string[] {
   const mediaTypes: string[] = [];
   for (const accept of accepts) {
     const [mediaType, ...params] = accept.split(';');
+    if (mediaType === undefined) continue; // If true, malformed header.
+
     const charset = params?.find(param => param.includes('charset=')) || 'charset=utf-8'; // utf-8 is assumed when not specified;
 
     if (charset !== 'charset=utf-8') {

packages/graphql-yoga/src/plugins/result-processor/regular.ts

@@ -35,7 +35,8 @@ export function processRegularResult(
       !Array.isArray(executionResult) &&
       areGraphQLErrors(executionResult.errors) &&
       executionResult.errors.some(
-        err => !err.extensions?.originalError || isGraphQLError(err.extensions.originalError),
+        err =>
+          !err.extensions?.['originalError'] || isGraphQLError(err.extensions['originalError']),
       ),
   );
 

packages/graphql-yoga/src/plugins/result-processor/sse.ts

@@ -11,7 +11,7 @@ export function getSSEProcessor(): ResultProcessor {
     let pingIntervalMs = 12_000;
 
     // for testing the pings, reduce the timeout
-    if (globalThis.process?.env?.NODE_ENV === 'test') {
+    if (globalThis.process?.env?.['NODE_ENV'] === 'test') {
       pingIntervalMs = 300;
     }