no-dead-code

Reports unused exports in JS/TS files.

Supports both ES and CommonJS modules out of the box.

Usage

In a project's root, run:

$ npx no-dead-code

Example output

src/client/util/common.js: Unused exports: colors, CONFIG_NAME
src/client/pages/FeedbackTarget/tabs/Results/QuestionResults/utils.js: Unused exports: countAverage, countStandardDeviation, countMedian

Options

--extensions (-e)

Specify which extensions are included.

Default: mjs cjs js ts tsx jsx

--ignore (-i)

Specify which paths are ignored.

By default, node_modules, .git, dist, build, migrations are always ignored. Values passed to -i are added to these.

--no-default-ignore

Turn off the default ignores node_modules, .git, dist, build, migrations.

Caveats

no-dead-code is far from complete, that's why its "best effort". The goal is to cover most typical coding standards, but it will inevitably output false positives and miss unused exports.

ES modules

Import and export declarations work pretty well. Dynamic imports are considered to import just everything.

CommonJS

Tracking all require-calls and module.exports assignments is a lot of effort, so only typical use cases are covered.

The following are seen by no-dead-code:

module.exports = foo // sees "default" exported. 

module.exports = { // "foo" and "bar" are seen exported
    foo,
    bar,
}

const foo = require('./foo') // everything imported from './foo'

const {
    foo,
    bar,
} = require('./foo') // "foo" and "bar" imported from './foo'

require('./foo')() // everything imported from './foo'

someFunction(require('./foo')) // everything imported from './foo'

Absolute paths

For absolute paths, the closest parent package.json and js/tsconfig are searched to resolve external dependencies and compilerOptions.baseUrl.

The config files are evaluated. Do not run this in a codebase that you do not trust.

NodeJS APIs are not yet supported and will be reported as not found.

Path aliases

TODO

Todo

• Formatted & colored output
• Deeper usage search