eslint-plugin-nodenext-extensions

ESLint plugin that enforces file extensions in relative imports/exports for NodeNext-style projects, with optional extension mapping (for example .ts -> .js).

Install

npm install --save-dev @hukopo/eslint-plugin-nodenext-extensions

Rule

• file-extension-in-import-ts

Options

["always", { extMapping: { ".ts": ".js", ".tsx": ".js" } }]

• always: require extension in relative imports/exports.
• extMapping: maps discovered source extension to required import extension.

Usage (Flat Config)

// eslint.config.js
const nodenextExtensions = require("@hukopo/eslint-plugin-nodenext-extensions");

module.exports = [
  {
    plugins: {
      "nodenext-extensions": nodenextExtensions,
    },
    rules: {
      "nodenext-extensions/file-extension-in-import-ts": [
        "error",
        "always",
        { extMapping: { ".ts": ".js", ".tsx": ".js" } },
      ],
    },
  },
];

What It Fixes

// before
import { Component } from "./component.ts";
export * from "./types";

// after
import { Component } from "./component.js";
export * from "./types.js";