72 lines
1.8 KiB
Markdown
72 lines
1.8 KiB
Markdown
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# import/default
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If a default import is requested, this rule will report if there is no default
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export in the imported module.
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For [ES7], reports if a default is named and exported but is not found in the
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referenced module.
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Note: for packages, the plugin will find exported names
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from [`jsnext:main`], if present in `package.json`.
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Redux's npm module includes this key, and thereby is lintable, for example.
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A module path that is [ignored] or not [unambiguously an ES module] will not be reported when imported.
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[ignored]: ../README.md#importignore
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[unambiguously an ES module]: https://github.com/bmeck/UnambiguousJavaScriptGrammar
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## Rule Details
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Given:
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```js
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// ./foo.js
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export default function () { return 42 }
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// ./bar.js
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export function bar() { return null }
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// ./baz.js
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module.exports = function () { /* ... */ }
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// node_modules/some-module/index.js
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exports.sharedFunction = function shared() { /* ... */ }
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```
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The following is considered valid:
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```js
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import foo from './foo'
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// assuming 'node_modules' are ignored (true by default)
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import someModule from 'some-module'
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```
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...and the following cases are reported:
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```js
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import bar from './bar' // no default export found in ./bar
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import baz from './baz' // no default export found in ./baz
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```
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## When Not To Use It
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If you are using CommonJS and/or modifying the exported namespace of any module at
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runtime, you will likely see false positives with this rule.
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This rule currently does not interpret `module.exports = ...` as a `default` export,
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either, so such a situation will be reported in the importing module.
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## Further Reading
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- Lee Byron's [ES7] export proposal
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- [`import/ignore`] setting
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- [`jsnext:main`] (Rollup)
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[ES7]: https://github.com/leebyron/ecmascript-more-export-from
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[`import/ignore`]: ../../README.md#importignore
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[`jsnext:main`]: https://github.com/rollup/rollup/wiki/jsnext:main
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