Check script which typechecks using Typescripts new Go port (#1075)

Author: mattzcarey

.github/workflows/main.yml

@@ -22,9 +22,9 @@ jobs:
                   cache: npm
 
             - run: npm ci
+            - run: npm run check
             - run: npm run build
             - run: npm test
-            - run: npm run lint
 
     publish:
         runs-on: ubuntu-latest

package-lock.json

@@ -59,7 +59,8 @@
         "dist"
     ],
     "scripts": {
-        "fetch:spec-types": "curl -o spec.types.ts https://raw.githubusercontent.com/modelcontextprotocol/modelcontextprotocol/refs/heads/main/schema/draft/schema.ts",
+        "fetch:spec-types": "curl -o ./src/spec.types.ts https://raw.githubusercontent.com/modelcontextprotocol/modelcontextprotocol/refs/heads/main/schema/draft/schema.ts",
+        "typecheck": "tsgo --noEmit",
         "build": "npm run build:esm && npm run build:cjs",
         "build:esm": "mkdir -p dist/esm && echo '{\"type\": \"module\"}' > dist/esm/package.json && tsc -p tsconfig.prod.json",
         "build:esm:w": "npm run build:esm -- -w",
@@ -69,6 +70,7 @@
         "prepack": "npm run build:esm && npm run build:cjs",
         "lint": "eslint src/ && prettier --check .",
         "lint:fix": "eslint src/ --fix && prettier --write .",
+        "check": "npm run fetch:spec-types && npm run typecheck && npm run lint",
         "test": "npm run fetch:spec-types && jest",
         "start": "npm run server",
         "server": "tsx watch --clear-screen=false scripts/cli.ts server",
@@ -111,6 +113,7 @@
         "@types/node": "^22.0.2",
         "@types/supertest": "^6.0.2",
         "@types/ws": "^8.5.12",
+        "@typescript/native-preview": "^7.0.0-dev.20251103.1",
         "eslint": "^9.8.0",
         "eslint-config-prettier": "^10.1.8",
         "jest": "^29.7.0",

package.json

@@ -311,7 +311,10 @@ export class StreamableHTTPClientTransport implements Transport {
             // if something happens reader will throw
             try {
                 // Create a pipeline: binary stream -> text decoder -> SSE parser
-                const reader = stream.pipeThrough(new TextDecoderStream()).pipeThrough(new EventSourceParserStream()).getReader();
+                const reader = stream
+                    .pipeThrough(new TextDecoderStream() as ReadableWritablePair<string, Uint8Array>)
+                    .pipeThrough(new EventSourceParserStream())
+                    .getReader();
 
                 while (true) {
                     const { value: event, done } = await reader.read();

src/client/streamableHttp.ts

@@ -15,8 +15,8 @@ import {
 } from '../../types.js';
 import { InMemoryEventStore } from '../shared/inMemoryEventStore.js';
 import { setupAuthServer } from './demoInMemoryOAuthProvider.js';
-import { OAuthMetadata } from 'src/shared/auth.js';
-import { checkResourceAllowed } from 'src/shared/auth-utils.js';
+import { OAuthMetadata } from '../../shared/auth.js';
+import { checkResourceAllowed } from '../../shared/auth-utils.js';
 
 import cors from 'cors';
 

src/examples/server/simpleStreamableHttp.ts

@@ -5,7 +5,7 @@ import { McpServer } from './mcp.js';
 import { createServer, type Server } from 'node:http';
 import { AddressInfo } from 'node:net';
 import { z } from 'zod';
-import { CallToolResult, JSONRPCMessage } from 'src/types.js';
+import { CallToolResult, JSONRPCMessage } from '../types.js';
 
 const createMockResponse = () => {
     const res = {

src/server/sse.test.ts

@@ -6,7 +6,7 @@
  *   (note: a few don't have SDK types, see MISSING_SDK_TYPES below)
  */
 import * as SDKTypes from './types.js';
-import * as SpecTypes from '../spec.types.js';
+import * as SpecTypes from './spec.types.js';
 import fs from 'node:fs';
 
 /* eslint-disable @typescript-eslint/no-unused-vars */
@@ -443,7 +443,7 @@ const sdkTypeChecks = {
 };
 
 // This file is .gitignore'd, and fetched by `npm run fetch:spec-types` (called by `npm run test`)
-const SPEC_TYPES_FILE = 'spec.types.ts';
+const SPEC_TYPES_FILE = 'src/spec.types.ts';
 const SDK_TYPES_FILE = 'src/types.ts';
 
 const MISSING_SDK_TYPES = [

src/spec.types.test.ts

@@ -13,9 +13,8 @@
         "resolveJsonModule": true,
         "isolatedModules": true,
         "skipLibCheck": true,
-        "baseUrl": ".",
         "paths": {
-            "pkce-challenge": ["node_modules/pkce-challenge/dist/index.node"]
+            "pkce-challenge": ["./node_modules/pkce-challenge/dist/index.node"]
         }
     },
     "include": ["src/**/*"],