dir-contains-path v0.0.0

dir-contains-path

Given two path strings, tells you if the first is an ancestor of the second.

Includes TypeScript typings.

// Absolute paths:
dirContainsPath('/foo', '/foo/bar/baz')          // true
dirContainsPath('/foo', '/foo/bar/baz')          // true

dirContainsPath('/foo', '/other/bar/baz')        // false
dirContainsPath('/foo', '/foo/../other/bar/baz') // false

// Relative descendant paths are resolved from the ancestor
dirContainsPath('/foo', 'anything')        // true
dirContainsPath('/foo', './anything')      // true
dirContainsPath('/foo', '../foo/anything') // true

dirContainsPath('/foo', '../outside')      // false
dirContainsPath('/foo', '../outside')      // false

// When both args are effectively the same path: always false
dirContainsPath('/foo', '/foo')         // false
dirContainsPath('/foo', '/foo/bar/..')  // false

Install

> npm install path-contains-path
# or
> yarn add path-contains-path

Use

import { dirContainsPath } from 'dir-contains-path'

if (dirContainsPath('/foo', '/foo/bar/baz')) {
	console.log('Yes it does')
}

API

dirContainsPath(ancestor: string, descendant: string, path?: path.PlatformPath): boolean

• ancestor – path representing a directory
• descendant - path representing another file/directory that you want to check is a descendant of ancestor
• path (optional) - the Node.js path module of your choice. Defaults to require('path').
  • In rare situations you might want to override this with e.g. require('path').posix or require('path').win32.

Errors

The function will throw an error:

• If either argument is a non-string, or an empty string.
• If the first argument (ancestor) is not an absolute path.
  • This is because it's unclear what the expectecd behaviour would be. You can always run the ancestor through path.resolve to make it absolute if that's what you want.

Alternatives

Several other packages do the exact same thing:

• subdir
• is-subdir

Why make dir-contains-path if several packages already exist doing roughly the same thing?

Mainly because I can never remember which way round the arguments go. For me, dirContainsPath(a, b) makes it unambiguous. Also because I wanted something stricter about strange input.