Registry / testing / babel-plugin-rewire-exports

babel-plugin-rewire-exports

library2.3.0jsnpmunverified

Babel plugin for stubbing ES6/ES2015 module exports in tests. Version 2.3.0 (stable, last release 2021) allows rewriting exported values in importing modules without modifying module internals. Unlike babel-plugin-rewire, it keeps imports and local variables intact. It generates rewire/stub functions (rewire for default, rewire$name for named exports, and restore). Works with Babel 7 (use 0.x for Babel 6), supports browser and Node ESM, and bundles with Webpack, Rollup, SystemJS, and CommonJS via env preset. Release cadence: infrequent, no recent updates.

testing

npm install babel-plugin-rewire-exports

github ↗package ↗

INSTALL

IMPORT

SIG · BABEL-PLUGIN-REWIR

babel-plugin-rewire-exports

testingjavascriptv2.3.0

Install

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Import

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Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

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

rewire (default export stub)

✓ import { rewire } from './my-module'

✗ import rewire from './my-module'

The plugin exports rewire as a named export, not default. It replaces the default export of the module.

rewire$name (named export stub)

✓ import { rewire$name } from './my-module'

✗ import { rewire_name } from './my-module'

For named exports, the stub is rewire$<exportName>. The dollar sign is part of the identifier.

restore

✓ import { restore } from './my-module'

✗ import restore from './my-module'

restore is a named export from the transformed module, not default.

Shows basic setup and usage: rewire a named export, restore original.

// .babelrc { "plugins": ["babel-plugin-rewire-exports"] } // text.js export let message = 'Hello world!'; // logger.js import {message} from './text.js'; export default function log() { console.log(message); } // test.js import {rewire$message, restore} from './text.js'; import log from './logger.js'; log(); // 'Hello world!' rewire$message('stubbed'); log(); // 'stubbed' restore(); log(); // 'Hello world!'

Debug

Known issues

breakingv2.0.0: Functions are rewritten as variables. Export default function foo() {} becomes var foo = function foo() {}; export { foo as default };

fix

In tests, access the function via the variable export, not the original function declaration. Use rewire$default for default exports.

affects: >=2.0.0

deprecatedv1.3.0: Constant exports behavior changed. Constants can't be rewired within the module; only the exported binding is mutable.

fix

If relying on rewiring const inside the module, use unsafeConst option or upgrade to >=1.3.0 and export as let/var.

affects: <1.3.0 >=1.0.0

gotchaPlugin must be placed before @babel/plugin-transform-modules-commonjs when targeting CommonJS.

fix

In .babelrc, order: ["babel-plugin-rewire-exports", "@babel/plugin-transform-modules-commonjs"]

affects: >=1.0.0

gotchaDefault export rewiring: rewire() stub replaces the default export, but the original default is kept and can be restored via restore().

fix

Use rewire(stub) for default exports, not named import default.

affects: >=1.0.0

gotchaIf the module already has top-level identifiers named rewire or restore, the generated stubs are renamed to rewire$default and restore$rewire.

fix

Check for name collisions and use the renamed stubs accordingly.

affects: >=1.0.0

Errors

Common errors & fixes

Error: Plugin babel-plugin-rewire-exports requires @babel/core but was not found.

Missing @babel/core peer dependency.

fix

Run npm install --save-dev @babel/core babel-plugin-rewire-exports

TypeError: Cannot assign to read only property 'message' of object '#<Object>'

Attempting to rewire a constant export without unsafeConst option.

fix

Add "unsafeConst": true to plugin options, or change export to let/var.

SyntaxError: Unexpected token $

Using node <8.5.0 or browser without ESM support for rewire$name identifier.

fix

Upgrade Node or use a bundler that supports the plugin's output.

Upgrade

Version history

2.3.0latest on npm

Audit

Dependencies

@babel/corerequiredRequires Babel 7 core as peer dependency.

Agent activity

18 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/asapach/babel-plugin-rewire-exports ↗

packagehttps://www.npmjs.com/package/babel-plugin-rewire-exports ↗