Elep

# npm-logical-tree [![npm version](https://img.shields.io/npm/v/npm-logical-tree.svg)](https://npm.im/npm-logical-tree) [![license](https://img.shields.io/npm/l/npm-logical-tree.svg)](https://npm.im/npm-logical-tree) [![Travis](https://img.shields.io/travis/npm/logical-tree.svg)](https://travis-ci.org/npm/logical-tree) [![AppVeyor](https://ci.appveyor.com/api/projects/status/github/npm/logical-tree?svg=true)](https://ci.appveyor.com/project/npm/logical-tree) [![Coverage Status](https://coveralls.io/repos/github/npm/logical-tree/badge.svg?branch=latest)](https://coveralls.io/github/npm/logical-tree?branch=latest)

[`npm-logical-tree`](https://github.com/npm/npm-logical-tree) is a Node.js
library that takes the contents of a `package.json` and `package-lock.json` (or
`npm-shrinkwrap.json`) and returns a nested tree data structure representing the
logical relationships between the different dependencies.

## Install

`$ npm install npm-logical-tree`

## Table of Contents

* [Example](#example)
* [Contributing](#contributing)
* [API](#api)
  * [`logicalTree`](#logical-tree)
  * [`logicalTree.node`](#make-node)
  * [`tree.isRoot`](#is-root)
  * [`tree.addDep`](#add-dep)
  * [`tree.delDep`](#del-dep)
  * [`tree.getDep`](#get-dep)
  * [`tree.path`](#path)
  * [`tree.hasCycle`](#has-cycle)
  * [`tree.forEach`](#for-each)
  * [`tree.forEachAsync`](#for-each-async)

### Example

```javascript
const fs = require('fs')
const logicalTree = require('npm-logical-tree')

const pkg = require('./package.json')
const pkgLock = require('./package-lock.json')

logicalTree(pkg, pkgLock)
// returns:
LogicalTree {
  name: 'npm-logical-tree',
  version: '1.0.0',
  address: null,
  optional: false,
  dev: false,
  bundled: false,
  resolved: undefined,
  integrity: undefined,
  requiredBy: Set { },
  dependencies:
   Map {
     'foo' => LogicalTree {
       name: 'foo',
       version: '1.2.3',
       address: 'foo',
       optional: false,
       dev: true,
       bundled: false,
       resolved: 'https://registry.npmjs.org/foo/-/foo-1.2.3.tgz',
       integrity: 'sha1-rYUK/p261/SXByi0suR/7Rw4chw=',
       dependencies: Map { ... },
       requiredBy: Set { ... },
     },
     ...
  }
}
```

### Contributing

The npm team enthusiastically welcomes contributions and project participation!
There's a bunch of things you can do if you want to contribute! The [Contributor
Guide](CONTRIBUTING.md) has all the information you need for everything from
reporting bugs to contributing entire new features. Please don't hesitate to
jump in if you'd like to, or even ask us questions if something isn't clear.

All participants and maintainers in this project are expected to follow [Code of
Conduct](CODE_OF_CONDUCT.md), and just generally be excellent to each other.

Please refer to the [Changelog](CHANGELOG.md) for project history details, too.

Happy hacking!

### API

#### <a name="logical-tree"></a> `> logicalTree(pkg, lock) -> LogicalTree`

Calculates a logical tree based on a matching `package.json` and
`package-lock.json` pair. A "logical tree" is a fully-nested dependency graph
for an npm package, as opposed to a physical tree which might be flattened.

`logical-tree` will represent deduplicated/flattened nodes using the same object
throughout the tree, so duplication can be checked by object identity.

##### Example

```javascript
const pkg = require('./package.json')
const pkgLock = require('./package-lock.json')

logicalTree(pkg, pkgLock)
// returns:
LogicalTree {
  name: 'npm-logical-tree',
  version: '1.0.0',
  address: null,
  optional: false,
  dev: false,
  bundled: false,
  resolved: undefined,
  integrity: undefined,
  requiredBy: Set { },
  dependencies:
   Map {
     'foo' => LogicalTree {
       name: 'foo',
       version: '1.2.3',
       address: 'foo',
       optional: false,
       dev: true,
       bundled: false,
       resolved: 'https://registry.npmjs.org/foo/-/foo-1.2.3.tgz',
       integrity: 'sha1-rYUK/p261/SXByi0suR/7Rw4chw=',
       requiredBy: Set { ... },
       dependencies: Map { ... }
     },
     ...
  }
}
```

#### <a name="make-node"></a> `> logicalTree.node(name, [address, [opts]]) -> LogicalTree`

Manually creates a new LogicalTree node.

##### Options

* `opts.version` - version of the node.
* `opts.optional` - is this node an optionalDep?
* `opts.dev` - is this node a devDep?
* `opts.bundled` - is this bundled?
* `opts.resolved` - resolved address.
* `opts.integrity` - SRI string.

##### Example
```javascript
logicalTree.node('hello', 'subpath:to:@foo/bar', {dev: true})
```