default.md

import/default

💼 This rule is enabled in the following configs: ❗ errors, ☑️ recommended.

If a default import is requested, this rule will report if there is no default export in the imported module.

For ES7, reports if a default is named and exported but is not found in the referenced module.

Note: for packages, the plugin will find exported names from jsnext:main, if present in package.json. Redux's npm module includes this key, and thereby is lintable, for example.

A module path that is ignored or not unambiguously an ES module will not be reported when imported.

Rule Details

Given:

// ./foo.js
export default function () { return 42 }

// ./bar.js
export function bar() { return null }

// ./baz.js
module.exports = function () { /* ... */ }

// node_modules/some-module/index.js
exports.sharedFunction = function shared() { /* ... */ }

The following is considered valid:

import foo from './foo'

// assuming 'node_modules' are ignored (true by default)
import someModule from 'some-module'

...and the following cases are reported:

import bar from './bar' // no default export found in ./bar
import baz from './baz' // no default export found in ./baz

When Not To Use It

If you are using CommonJS and/or modifying the exported namespace of any module at runtime, you will likely see false positives with this rule.

This rule currently does not interpret module.exports = ... as a default export, either, so such a situation will be reported in the importing module.

Further Reading

• Lee Byron's ES7 export proposal
• import/ignore setting
• jsnext:main (Rollup)