no-duplicates

💼 This rule is enabled in the following configs: recommended, typescript. 🔧 This rule is automatically fixable by the --fix CLI option.

Rule DetailsCopy Anchor Link

Two import statements of the same module in one scope are reported when they could be one statement, or one of them adds nothing: two value imports (named, default, inline type, side-effect, namespace) of one module, or two import type statements of one module.

The same module is the file the resolver sees, so ./m and ./m.js (for m.ts) and ./m/index are one module, while ./m?raw is a different module to a bundler.

Not reported:

• import type beside a value import of the same module: the type-only form is erased, and folding it into the value import changes what is emitted.
• A namespace import beside a named import (import * as ns and import { a }): import * as ns, { a } is not valid syntax, so the two cannot be one statement and neither is redundant.
• Imports in two different declare module 'x' {} blocks: they belong to two ambient modules.

❌ IncorrectCopy Anchor Link

import { a } from './m';
import { b } from './m';

import './m';
import { c } from './m.js';

import type { A } from './types';
import type { B } from './types';

✅ CorrectCopy Anchor Link

import { a, b } from './m';
import type { A } from './m';
import * as ns from './m';
import raw from './m?raw';

OptionsCopy Anchor Link

[]

ImplementationCopy Anchor Link

• Source Code
• Test Cases

OWASP FoundationCopy Anchor Link

• Category: A00:2021 - General Security

Use this rule

npm install -D oxlint-plugin-import-next

{  "jsPlugins": ["oxlint-plugin-import-next"],  "rules": {    "import-next/no-duplicates": "error"  }}

import { defineConfig } from 'vite-plus';export default defineConfig({  lint: {    jsPlugins: ['oxlint-plugin-import-next'],    rules: {      'import-next/no-duplicates': 'error',    },  },});