Registry / serialization / node-source-walk

node-source-walk

library7.0.1jsnpmunverified

node-source-walk is a JavaScript utility library designed for synchronously traversing Abstract Syntax Trees (ASTs) or raw source code strings. It allows developers to apply a callback function to every node within the AST, with the crucial capability to halt the traversal prematurely using `stopWalking()`. The current stable version is 7.0.1. Releases tend to align with Node.js LTS updates, primarily dropping support for older Node.js versions. A key differentiator is its flexibility in supporting both top-down (`walk`, `traverse`) and bottom-up (`moonwalk`) traversals, accepting either source code or a pre-parsed AST, and offering the option to replace its default `@babel/parser` with a custom parser.

serialization

npm install node-source-walk

github ↗package ↗

INSTALL

IMPORT

SIG · NODE-SOURCE-WALK

node-source-walk

serializationjavascriptv7.0.1

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.

Walker

✓ import Walker from 'node-source-walk';

✗ import { Walker } from 'node-source-walk';

The Walker class is the default export for ESM modules. Avoid named import syntax.

Walker

✓ const Walker = require('node-source-walk');

✗ const { Walker } = require('node-source-walk');

For CommonJS, the Walker class is the default export. Destructuring will not work as expected.

Walker (Type)

✓ import type { WalkerOptions } from 'node-source-walk';

For TypeScript projects, import the `WalkerOptions` interface to type the constructor options, if type definitions are available (e.g., via `@types/node-source-walk` or bundled).

This quickstart demonstrates how to instantiate the Walker class, traverse source code, identify specific AST node types (like 'FunctionDeclaration' or 'JSXElement'), and efficiently stop the traversal once a desired node is found. It also shows how to configure the internal parser with custom plugins like 'jsx'.

import Walker from 'node-source-walk'; // Example source code string const src = ` const add = (a, b) => a + b; function subtract(a, b) { return a - b; } console.log(add(5, 3)); console.log(subtract(10, 4)); `; const walker = new Walker(); let foundFunctionDeclaration = false; console.log('Walking AST for function declarations...'); walker.walk(src, node => { if (node.type === 'FunctionDeclaration') { console.log(`Found function declaration: ${node.id.name}`); foundFunctionDeclaration = true; // Stop walking after finding the first one walker.stopWalking(); } }); if (!foundFunctionDeclaration) { console.log('No function declarations found.'); } // Example with custom parser options (for JSX) const jsxSrc = ` import React from 'react'; function MyComponent() { return <div>Hello, JSX!</div>; } `; const jsxWalker = new Walker({ plugins: ['jsx'] // Ensure JSX plugin is enabled for parsing }); console.log('\nWalking AST for JSX elements...'); let foundJsxElement = false; jsxWalker.walk(jsxSrc, node => { if (node.type === 'JSXElement') { console.log('Found a JSXElement!'); foundJsxElement = true; jsxWalker.stopWalking(); } }); if (!foundJsxElement) { console.log('No JSX elements found.'); }

Debug

Known issues

breakingVersion 7.0.0 and above drop support for Node.js versions older than 18. Projects running on Node.js 16 or earlier must upgrade their Node.js environment or remain on a previous major version of `node-source-walk`.

fix

Upgrade your Node.js runtime to version 18 or newer. If an upgrade is not possible, pin `node-source-walk` to a version compatible with your Node.js environment (e.g., `<7.0.0` for Node.js 16).

affects: >=7.0.0

breakingIn version 6.0.0, the `shouldStop` and `reverseTraverse` methods were made private. Direct access or usage of these methods in your application logic will now fail.

fix

Refactor code that directly called `shouldStop` or `reverseTraverse`. Instead, use the public `stopWalking()` method to halt traversal. The `moonwalk` method provides public access to reverse traversal functionality.

affects: >=6.0.0

breakingVersion 6.0.0 dropped support for Node.js 12. If you are migrating from a version below 6.0.0 and still using Node.js 12, an upgrade to Node.js 14 or higher (or eventually Node.js 18 for v7+) is required.

fix

Upgrade your Node.js runtime to version 14 or newer, ideally to Node.js 18+ to be compatible with the latest major versions.

affects: >=6.0.0 <7.0.0

gotchaWhen providing a custom parser to `Walker`, ensure it exposes a `.parse` method that accepts a string and returns a valid AST. The library passes all other options to this custom parser.

fix

Verify that your custom parser adheres to the expected `.parse(sourceString)` signature and returns a compatible AST structure. Consult `@babel/parser`'s documentation for AST shape reference.

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: Walker is not a constructor

Attempting to import `Walker` using named import syntax (`import { Walker } from '...'`) or destructuring (`const { Walker } = require('...')`) when it is exported as a default.

fix

Use default import for ESM (`import Walker from 'node-source-walk';`) or direct `require` assignment for CommonJS (`const Walker = require('node-source-walk');`).

SyntaxError: Unexpected token 'import' (or similar parsing errors for modern JS/TS features)

The default `@babel/parser` might not have the necessary plugins enabled to parse specific syntax (e.g., JSX, Flow, TypeScript).

fix

Initialize the `Walker` with `plugins` option to enable required `@babel/parser` plugins, for example: `new Walker({ plugins: ['jsx', 'typescript'] })`.

Error: node-source-walk requires Node.js version >= 18.

Running a version of `node-source-walk` (v7.0.0 or higher) on an unsupported Node.js runtime environment (e.g., Node.js 16).

fix

Upgrade your Node.js runtime to version 18 or newer. Check your project's `engines` field in `package.json` for compatibility.

Upgrade

Version history

7.0.1latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

2 hits · last 30 days

node

Resources

githubhttps://github.com/dependents/node-source-walk ↗

packagehttps://www.npmjs.com/package/node-source-walk ↗