Registry /
testing / babel-preset-power-assert
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
muslnode 18–226 runs
build_error
glibcnode 18–226 runs
build_error
Code
Verified usage
Verified import paths — ran on the pinned version, not inferred.
defaultPreset
✓ // In .babelrc or babel.config.js
{
"presets": ["power-assert"]
}
✗ // Wrong: using require('babel-preset-power-assert') directly as a function
var preset = require('babel-preset-power-assert');
The preset is used as a Babel preset string, not imported as a module in JavaScript code.
babel-plugin-empower-assert
✓ import { empowerAssert } from 'babel-preset-power-assert';
✗ const empowerAssert = require('babel-preset-power-assert').empowerAssert;
This preset re-exports babel-plugin-empower-assert and babel-plugin-espower. However, direct import is not common; usually you just use the preset string.
babel-plugin-espower
✓ import { espower } from 'babel-preset-power-assert';
✗ const espower = require('babel-preset-power-assert').espower;
Same as above. The plugins are exported for advanced usage, but the preset string is the recommended approach.
config
✓ {
"presets": [
["power-assert", {
"empowerAssert": { /* options */ },
"espower": { /* options */ }
}]
]
}
✗ // Wrong: passing options as second argument to require
const preset = require('babel-preset-power-assert')(options);
Options are passed as an array entry in the presets list, not via function call.
Shows setup of babel-preset-power-assert with Babel, including installation, configuration, and a sample test using power-assert assert.
// 1. Install dependencies:
// npm install --save-dev babel-preset-power-assert power-assert
// 2. Create babel.config.js (or .babelrc):
module.exports = {
presets: ['power-assert']
};
// 3. Write a test file (e.g., test.js):
const assert = require('power-assert');
describe('Array', () => {
it('should have length 3', () => {
const arr = [1, 2, 3];
assert(arr.length === 3);
});
});
// 4. Run with Babel:
// npx babel test.js --out-file test-transpiled.js && node test-transpiled.js
Errors
Common errors & fixes
Error: Cannot find module 'babel-preset-power-assert'
Missing package installation or incorrect npm install command.
fixRun: npm install --save-dev babel-preset-power-assert
TypeError: Cannot read property 'power-assert' of undefined
Missing power-assert runtime package.
fixInstall power-assert: npm install --save-dev power-assert
ReferenceError: assert is not defined
power-assert module not imported in your test file.
fixAdd const assert = require('power-assert'); at the top of your file. Error: Requires Babel "7.0.0-0" but was loaded with "6.26.3"
Using babel-preset-power-assert v3.x with Babel 6.
fixUse babel-preset-power-assert@2.0.0 for Babel 6, or upgrade to Babel 7.
Audit
Dependencies
power-assertrequiredRuntime dependency for assertion enhancement; must be installed alongside the preset.