Support typescript 5.7

[pcaversaccio]

Link to the code that reproduces this issue

https://github.com/microsoft/TypeScript/releases/tag/v5.7.2

To Reproduce

The full announcement: https://devblogs.microsoft.com/typescript/announcing-typescript-5-7.

Current vs. Expected behavior

1. npx next build will fail with something like if upgraded to typescript 5.7.2:

   ▲ Next.js 15.0.3

   Linting and checking validity of types  ..Failed to compile.

   Linting and checking validity of types  ..../eslint.config.js:10:1
Type error: The inferred type of '(Missing)' cannot be named without a reference to '.pnpm/@typescript-eslint+utils@8.15.0_eslint@9.15.0_jiti@2.4.0__typescript@5.7.2/node_modules/@typescript-eslint/utils/dist/ts-eslint'. This is likely not portable. A type annotation is necessary.

   8 | /* eslint-enable @typescript-eslint/no-require-imports */
   9 |
> 10 | module.exports = tseslint.config(

You can repro using my code here: https://github.com/pcaversaccio/createx/tree/main/interface.

Provide environment information

Operating System:
  Platform: win32
  Arch: x64
  Version: Windows 11 Pro
  Available memory (MB): 16190
  Available CPU cores: 8
Binaries:
  Node: 22.11.0
  npm: 10.9.1
  Yarn: 1.22.22
  pnpm: 9.14.2
Relevant Packages:
  next: 15.0.3 // Latest available version is detected (15.0.3).
  eslint-config-next: 15.0.3
  react: 18.3.1
  react-dom: 18.3.1
  typescript: 5.7.2
Next.js Config:
  output: export

Which area(s) are affected? (Select all that apply)

Linting

Which stage(s) are affected? (Select all that apply)

next build (local)

Additional context

No response

[pcaversaccio]

Fixing it for now via an explicit type annotation:

/* eslint-disable @typescript-eslint/no-require-imports */
const eslint = require("@eslint/js");
const tseslint = require("typescript-eslint");
const next = require("@next/eslint-plugin-next");
const react = require("eslint-plugin-react");
const reactHooks = require("eslint-plugin-react-hooks");
const eslintConfigPrettier = require("eslint-config-prettier");
/* eslint-enable @typescript-eslint/no-require-imports */

/** @type {import('typescript-eslint').TSESLint.FlatConfig.ConfigArray} */
module.exports = tseslint.config(
  {
    files: ["**/*.{js,ts,tsx}"],
    extends: [
      eslint.configs.recommended,
      ...tseslint.configs.recommended,
      ...tseslint.configs.stylistic,
      eslintConfigPrettier,
    ],
    plugins: {
      "@typescript-eslint": tseslint.plugin,
      "@next/next": next,
      react: react,
      "react-hooks": reactHooks,
    },
    rules: {
      ...next.configs.recommended.rules,
      ...react.configs["jsx-runtime"].rules,
      ...reactHooks.configs.recommended.rules,
    },
    languageOptions: {
      ecmaVersion: "latest",
      parser: tseslint.parser,
      parserOptions: {
        project: true,
      },
    },
  },
  {
    ignores: ["node_modules/**", ".next/**", "next-env.d.ts", "dist/**"],
  },
);

[samcx]

@pcaversaccio Can you provide us a :repro: so we can take a look?

[pcaversaccio]

Sure: https://github.com/pcaversaccio/createx

I fixed it now via this line: https://github.com/pcaversaccio/createx/blob/main/interface/eslint.config.js#L10. So remove it before you run npx next build. After that you will see the error.

The easiest way to set it up locally (you don't need to submodules), clone the repo, run pnpm install and pnpm build:interface in the root directory of the repository.