Registry / testing / babel-check-duplicated-nodes

babel-check-duplicated-nodes

library1.0.0jsnpmunverified

Babel helper utility (v1.0.0) that checks an AST for duplicated nodes, throwing a descriptive error if any are found. Originally extracted from Babel's test fixture runner, this tool helps Babel transform authors catch subtle bugs caused by node reuse. It is a niche package with a single API call, no active release cadence, and is intended for internal use during transform development rather than general production.

testing

npm install babel-check-duplicated-nodes

github ↗package ↗

INSTALL

IMPORT

SIG · BABEL-CHECK-DUPLIC

babel-check-duplicated-nodes

testingjavascriptv1.0.0

Install

—

Import

—

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.

checkDuplicatedNodes

✓ import { checkDuplicatedNodes } from 'babel-check-duplicated-nodes'

✗ import checkDuplicatedNodes from 'babel-check-duplicated-nodes'

Package exports a named function, not a default export.

Demonstrates how to use checkDuplicatedNodes with @babel/core to detect duplicated AST nodes.

import { checkDuplicatedNodes } from 'babel-check-duplicated-nodes'; import * as babel from '@babel/core'; const code = 'const x = 1; const y = 2;'; const ast = babel.parseSync(code, { filename: 'test.js' }); // Simulate a duplicated node: reuse the same node twice const duplicateNode = ast.program.body[0]; ast.program.body.push(duplicateNode); try { checkDuplicatedNodes(babel, ast); } catch (e) { console.error(e.message); }

Debug

Known issues

gotchaThe pattern 'require('babel-check-duplicated-nodes').default' is incorrect; the package does not have a default export.

fix

Use 'const { checkDuplicatedNodes } = require('babel-check-duplicated-nodes')'.

affects: >=1.0.0

gotchaThis package is intended for internal use by Babel transform authors, not for general AST manipulation. Incorrect usage may produce false negatives.

fix

Ensure you only call this function on ASTs generated by Babel's parser, not third-party parsers.

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: checkDuplicatedNodes is not a function

Default import usage instead of named import.

fix

Use `import { checkDuplicatedNodes } from 'babel-check-duplicated-nodes'` or `const { checkDuplicatedNodes } = require('babel-check-duplicated-nodes')`.

Cannot find module 'babel-check-duplicated-nodes'

Package not installed or missing from node_modules.

fix

Run `npm install babel-check-duplicated-nodes --save-dev`.

Upgrade

Version history

1.0.0latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

18 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/Andarist/babel-check-duplicated-nodes ↗

packagehttps://www.npmjs.com/package/babel-check-duplicated-nodes ↗