rollup-plugin-power-assert

0.2.0 verified Mon Apr 27 auth: no javascript

Rollup and Vite plugin for power-assert, providing descriptive assertion messages through the standard Node.js assert interface. Current stable version is 0.2.0. It transforms assertion expressions (e.g., assert(ary.indexOf(zero) === two)) into detailed, labeled output showing intermediate values. The library supports both Rollup and Vite/Vitest with minimal configuration, and is part of the power-assert monorepo. Key differentiators include zero API overhead and compatibility with Vitest's assert API.

Common errors

error Cannot find module '@power-assert/runtime' ↓

cause Missing peer dependency @power-assert/runtime

fix

npm install --save-dev @power-assert/runtime

error TypeError: (0 , _rollupPluginPowerAssert.powerAssert) is not a function ↓

cause Using default import instead of named import

fix

Change to: import { powerAssert } from 'rollup-plugin-power-assert'

error AssertionError: assert(...) expression not transformed ↓

cause The file is not included in the plugin's include pattern

fix

Ensure the file path matches the include glob pattern in the plugin options.

Warnings

gotcha The plugin transforms assert() calls only; it does not transform other assertion libraries like chai or expect. ↓

fix Use Node.js assert module or Vitest's assert API. For other libraries, consider alternative power-assert wrappers.

gotcha The plugin requires the @power-assert/runtime package as a peer dependency. Failing to install it can result in runtime errors. ↓

fix Install the peer dependency: npm install --save-dev @power-assert/runtime

deprecated The plugin may be deprecated in future versions of power-assert monorepo; check for migration notes. ↓

fix Monitor the repository for deprecation notices and plan migration to alternative assertion enhancement tools.

Install

npm install rollup-plugin-power-assert

yarn add rollup-plugin-power-assert

pnpm add rollup-plugin-power-assert

Imports

powerAssert

wrong

import powerAssert from 'rollup-plugin-power-assert'

correct

import { powerAssert } from 'rollup-plugin-power-assert'

Must use named import; default import is not available.

powerAssert (CommonJS)

wrong

const powerAssert = require('rollup-plugin-power-assert')

correct

const { powerAssert } = require('rollup-plugin-power-assert')

CommonJS requires destructuring; the module exports an object with named exports.

type definition
```
import type { PowerAssertOptions } from 'rollup-plugin-power-assert'
```
TypeScript types are included; use named type import for configuration options.

Quickstart

Configure Vite/Vitest with the powerAssert plugin to enable descriptive assertion messages in test files.

import { defineConfig } from 'vite';
import { powerAssert } from 'rollup-plugin-power-assert';

const testPattern = 'examples/**/__tests__/**/*.test.mts';

export default defineConfig({
  plugins: [
    powerAssert({
      include: testPattern,
    }),
  ],
  test: {
    include: testPattern,
  },
});