babel-traverse

library6.26.0jsnpmunverified

babel-traverse (v6.26.0) is the deprecated Babel 6 package for traversing and manipulating ASTs. It was the core traversal engine behind Babel 6, maintaining tree state and allowing node replacement, removal, and insertion. Key differentiator: provides a visitor pattern for AST mutation via Path objects. Since Babel 7, this package has been replaced by @babel/traverse. v6.26.0 is the final release of the standalone package; it depends on babel-types and babel-generator. It does not ship TypeScript definitions, and is CommonJS-only. The v8.0.0-rc.3 release exists but the babel-traverse name is no longer published under the @babel scope.

devops

npm install babel-traverse

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · BABEL-TRAVERSE

babel-traverse

devopsjavascriptv6.26.0

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.

default export (traverse)

✓ import traverse from 'babel-traverse';

✗ const traverse = require('babel-traverse').default;

The default export is a function; CommonJS require yields the function directly, no .default needed.

main traverse function (CommonJS)

✓ const traverse = require('babel-traverse');

✗ import { traverse } from 'babel-traverse';

Named export 'traverse' does not exist; the module exports a single default function.

no named exports

✓ The module only has a default export; no named exports like 'Visitor' or 'Path' are publicly exported.

✗ import { Visitor } from 'babel-traverse';

Types must be obtained from @babel/traverse or defined locally.

Parses code with babylon, traverses AST using babel-traverse to rename identifier 'n' to 'x', then generates output with babel-generator.

import * as babylon from 'babylon'; import traverse from 'babel-traverse'; import generate from 'babel-generator'; const code = `function square(n) { return n * n; }`; const ast = babylon.parse(code); traverse(ast, { enter(path) { if (path.isIdentifier({ name: 'n' })) { path.node.name = 'x'; } } }); const output = generate(ast, {}, code); console.log(output.code); // 'function square(x) { return x * x; }'

Debug

Known issues

deprecatedbabel-traverse is deprecated in favor of @babel/traverse (Babel 7+). This package is no longer maintained.

fix

Migrate to @babel/traverse: npm install @babel/traverse and update imports to import traverse from '@babel/traverse'.

affects: 6.x

breakingBabel 8 (v8.0.0-rc.x) introduces strictNullChecks for traverse, which may break code that relied on nullable path properties being unchecked.

fix

Upgrade to @babel/traverse and add null checks for path properties (e.g., path.parent, path.container) as they may be null.

affects: >=8.0.0-rc.0

gotchaThe package does not ship TypeScript declarations; using with TypeScript requires custom type stubs or migration to @babel/traverse.

fix

Either write a .d.ts file (e.g., declare module 'babel-traverse' { const traverse: any; export default traverse; }) or switch to @babel/traverse.

affects: 6.x

gotchababel-traverse v6 is CommonJS-only and cannot be imported as a named export; default import or require is required.

fix

Use `import traverse from 'babel-traverse'` (with esModuleInterop) or `const traverse = require('babel-traverse')`.

affects: 6.x

gotchaNo support for async/await or promise-based traversal; all visitor callbacks are synchronous.

fix

Consider using @babel/traverse which supports async visitors via `traverse(ast, { enter: async function(path) { ... } })`.

affects: 6.x

Errors

Common errors & fixes

TypeError: traverse is not a function

Using named import like `import { traverse } from 'babel-traverse'` when the package has only a default export.

fix

Use `import traverse from 'babel-traverse'` or `const traverse = require('babel-traverse')`.

Cannot find module 'babel-traverse'

The package is not installed, or you are using a bundler that cannot resolve the name (e.g., Webpack with strict module resolution).

fix

Run `npm install babel-traverse@6.26.0` or switch to `@babel/traverse` for Babel 7+ compatibility.

Error: Cannot find module 'babel-types' from 'babel-traverse'

babel-traverse has a peer dependency on babel-types which is not installed.

fix

Run `npm install babel-types@6.26.0`.

TypeError: path.isIdentifier is not a function

Using a malformed visitor object or the path object is not a valid NodePath. Common when overriding enter without function.

fix

Ensure visitor callbacks are functions: `traverse(ast, { enter(path) { ... } })`.

Upgrade

Version history

6.26.0latest on npm

Audit

Dependencies

babel-typesrequiredRequired for AST node type checking and construction; used internally by traverse.

babel-generatoroptionalMay be needed for code generation from traversed AST.

babylonoptionalCommonly used together for parsing code before traversal.

Agent activity

14 hits · last 30 days

node

Resources

githubhttps://github.com/babel/babel ↗

packagehttps://www.npmjs.com/package/babel-traverse ↗

homepagehttps://babeljs.io/ ↗