import-fresh

library4.0.0jsnpmunverified

Import-fresh bypasses the Node.js module cache to force a fresh import of a module, useful for testing and hot-reloading scenarios. Version 4.0.0 (latest stable, released 2025) requires Node.js ≥22.15 due to its use of ESM module loader hooks. Unlike older cache-clearing approaches (e.g., delete require.cache), import-fresh works with ESM and is the only maintained solution for Node's native ES module system. It uses a unique cache-busting URL per call, which grows memory over time (intended for development only). Sindre Sorhus maintains it with monthly releases.

testing

npm install import-fresh

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · IMPORT-FRESH

import-fresh

testingjavascriptv4.0.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

createImportFresh

✓ import createImportFresh from 'import-fresh'

✗ const createImportFresh = require('import-fresh')

Default export only; ESM-only since v4. CommonJS require will fail.

importFresh (returned function)

✓ const importFresh = createImportFresh(import.meta.url); const mod = await importFresh('./foo.js')

✗ const importFresh = createImportFresh(__filename)

parentURL must be a URL string, not a file path. import.meta.url is the correct argument in ESM.

TypeScript types

✓ import createImportFresh from 'import-fresh'

✗ import { createImportFresh } from 'import-fresh'

The package ships TypeScript types but the export is default, not named. Named import will cause a type error.

Demonstrates creating an importFresh function and using it to bypass the module cache, showing state reset.

import createImportFresh from 'import-fresh'; import { strict as assert } from 'node:assert'; // Simulate a module with mutable state const loadIncrement = () => ` let count = 0; export default function increment() { count += 1; return count; } `; const importFresh = createImportFresh(import.meta.url); // First import const { default: increment } = await importFresh('./fixture.js'); // pretend fixture.js contains loadIncrement() assert.equal(increment(), 1); assert.equal(increment(), 2); // Fresh import resets state const { default: freshIncrement } = await importFresh('./fixture.js'); assert.equal(freshIncrement(), 1); console.log('All tests passed.');

Debug

Known issues

gotchaMemory leak: each call grows the ESM module cache indefinitely.

fix

Use only in development or short-lived processes. Not suitable for production long-running servers.

affects: >=1.0.0

breakingESM-only since v4: require() will throw because the package uses module loader hooks.

fix

Convert to ESM (type: module in package.json or .mjs extension).

affects: >=4.0.0

breakingNode.js version requirement bumped to 22.15 in v4.

fix

Upgrade Node.js to >=22.15 or stay on v3 (which uses older Node.js APIs).

affects: >=4.0.0

gotchaparentURL must be a URL (e.g., import.meta.url), not a file path (__filename).

fix

Pass import.meta.url; for CJS compatibility, use url.pathToFileURL(__filename).

affects: >=4.0.0

deprecatedThe skipNodeModules option is process-global; all calls in the same process must use the same value.

fix

Set skipNodeModules consistently; if you need different behaviors, run in separate processes.

affects: >=4.0.0

Errors

Common errors & fixes

TypeError: createImportFresh is not a function

Default import used as named import: import { createImportFresh } from 'import-fresh'

fix

import createImportFresh from 'import-fresh'

Error [ERR_REQUIRE_ESM]: require() of ES Module /path/to/import-fresh/index.js not supported.

Trying to require() an ESM-only package.

fix

Use import instead of require; ensure your project is ESM (type: module) or use dynamic import().

TypeError [ERR_INVALID_ARG_TYPE]: The "parentURL" argument must be a string.

Passing __filename instead of a URL string.

fix

Pass import.meta.url or new URL(import.meta.url).href

Upgrade

Version history

4.0.0latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

8 hits · last 30 days

node

Resources

githubhttps://github.com/sindresorhus/import-fresh ↗

packageimport-fresh ↗

homepagehttps://github.com/sindresorhus/import-fresh#readme ↗