resolve

implements the node require.resolve() algorithm such that you can require.resolve() on behalf of a file asynchronously and synchronously

example

asynchronously resolve:

var resolve = require('resolve');
resolve('tap', { basedir: __dirname }, function (err, res) {
    if (err) console.error(err)
    else console.log(res)
});

$ node example/async.js
/home/substack/projects/node-resolve/node_modules/tap/lib/main.js

synchronously resolve:

var resolve = require('resolve');
var res = resolve.sync('tap', { basedir: __dirname });
console.log(res);

$ node example/sync.js
/home/substack/projects/node-resolve/node_modules/tap/lib/main.js

methods

var resolve = require('resolve')

resolve(id, opts={}, cb)

Asynchronously resolve the module path string id into cb(err, res [, pkg]), where pkg (if defined) is the data from package.json.

options are:

• opts.basedir - directory to begin resolving from

• opts.package - package.json data applicable to the module being loaded

• opts.extensions - array of file extensions to search in order

• opts.readFile - how to read files asynchronously

• opts.isFile - function to asynchronously test whether a file exists

• opts.packageFilter(pkg, pkgfile) - transform the parsed package.json contents before looking at the "main" field

• opts.pathFilter(pkg, path, relativePath) - transform a path within a package

  • pkg - package data
  • path - the path being resolved
  • relativePath - the path relative from the package.json location
  • returns - a relative path that will be joined from the package.json location

• opts.paths - require.paths array to use if nothing is found on the normal node_modules recursive walk (probably don't use this)

• opts.moduleDirectory - directory (or directories) in which to recursively look for modules. default: "node_modules"

• opts.preserveSymlinks - if true, doesn't resolve basedir to real path before resolving. This is the way Node resolves dependencies when executed with the --preserve-symlinks flag.

default opts values:

{
    paths: [],
    basedir: __dirname,
    extensions: [ '.js' ],
    readFile: fs.readFile,
    isFile: function isFile(file, cb) {
        fs.stat(file, function (err, stat) {
            if (!err) {
                return cb(null, stat.isFile() || stat.isFIFO());
            }
            if (err.code === 'ENOENT' || err.code === 'ENOTDIR') return cb(null, false);
            return cb(err);
        });
    },
    moduleDirectory: 'node_modules',
    preserveSymlinks: false
}

resolve.sync(id, opts)

Synchronously resolve the module path string id, returning the result and throwing an error when id can't be resolved.

options are:

• opts.basedir - directory to begin resolving from

• opts.extensions - array of file extensions to search in order

• opts.readFile - how to read files synchronously

• opts.isFile - function to synchronously test whether a file exists

• opts.packageFilter(pkg, pkgfile) - transform the parsed package.json contents before looking at the "main" field

• opts.pathFilter(pkg, path, relativePath) - transform a path within a package

  • pkg - package data
  • path - the path being resolved
  • relativePath - the path relative from the package.json location
  • returns - a relative path that will be joined from the package.json location

• opts.paths - require.paths array to use if nothing is found on the normal node_modules recursive walk (probably don't use this)

• opts.moduleDirectory - directory (or directories) in which to recursively look for modules. default: "node_modules"

• opts.preserveSymlinks - if true, doesn't resolve basedir to real path before resolving. This is the way Node resolves dependencies when executed with the --preserve-symlinks flag.

default opts values:

{
    paths: [],
    basedir: __dirname,
    extensions: [ '.js' ],
    readFileSync: fs.readFileSync,
    isFile: function isFile(file) {
        try {
            var stat = fs.statSync(file);
        } catch (e) {
            if (e && (e.code === 'ENOENT' || e.code === 'ENOTDIR')) return false;
            throw e;
        }
        return stat.isFile() || stat.isFIFO();
    },
    moduleDirectory: 'node_modules',
    preserveSymlinks: false
}

resolve.isCore(pkg)

Return whether a package is in core.

install

With npm do:

npm install resolve

license

MIT