1 var fs = require('fs');
2 var path = require('path');
3 var caller = require('./caller');
4 var nodeModulesPaths = require('./node-modules-paths');
5 var normalizeOptions = require('./normalize-options');
6 var isCore = require('is-core-module');
8 var realpathFS = fs.realpath && typeof fs.realpath.native === 'function' ? fs.realpath.native : fs.realpath;
10 var defaultIsFile = function isFile(file, cb) {
11 fs.stat(file, function (err, stat) {
13 return cb(null, stat.isFile() || stat.isFIFO());
15 if (err.code === 'ENOENT' || err.code === 'ENOTDIR') return cb(null, false);
20 var defaultIsDir = function isDirectory(dir, cb) {
21 fs.stat(dir, function (err, stat) {
23 return cb(null, stat.isDirectory());
25 if (err.code === 'ENOENT' || err.code === 'ENOTDIR') return cb(null, false);
30 var defaultRealpath = function realpath(x, cb) {
31 realpathFS(x, function (realpathErr, realPath) {
32 if (realpathErr && realpathErr.code !== 'ENOENT') cb(realpathErr);
33 else cb(null, realpathErr ? x : realPath);
37 var maybeRealpath = function maybeRealpath(realpath, x, opts, cb) {
38 if (opts && opts.preserveSymlinks === false) {
45 var defaultReadPackage = function defaultReadPackage(readFile, pkgfile, cb) {
46 readFile(pkgfile, function (readFileErr, body) {
47 if (readFileErr) cb(readFileErr);
50 var pkg = JSON.parse(body);
59 var getPackageCandidates = function getPackageCandidates(x, start, opts) {
60 var dirs = nodeModulesPaths(start, opts, x);
61 for (var i = 0; i < dirs.length; i++) {
62 dirs[i] = path.join(dirs[i], x);
67 module.exports = function resolve(x, options, callback) {
70 if (typeof options === 'function') {
74 if (typeof x !== 'string') {
75 var err = new TypeError('Path must be a string.');
76 return process.nextTick(function () {
81 opts = normalizeOptions(x, opts);
83 var isFile = opts.isFile || defaultIsFile;
84 var isDirectory = opts.isDirectory || defaultIsDir;
85 var readFile = opts.readFile || fs.readFile;
86 var realpath = opts.realpath || defaultRealpath;
87 var readPackage = opts.readPackage || defaultReadPackage;
88 if (opts.readFile && opts.readPackage) {
89 var conflictErr = new TypeError('`readFile` and `readPackage` are mutually exclusive.');
90 return process.nextTick(function () {
94 var packageIterator = opts.packageIterator;
96 var extensions = opts.extensions || ['.js'];
97 var includeCoreModules = opts.includeCoreModules !== false;
98 var basedir = opts.basedir || path.dirname(caller());
99 var parent = opts.filename || basedir;
101 opts.paths = opts.paths || [];
103 // ensure that `basedir` is an absolute path at this point, resolving against the process' current working directory
104 var absoluteStart = path.resolve(basedir);
110 function (err, realStart) {
112 else init(realStart);
117 function init(basedir) {
118 if ((/^(?:\.\.?(?:\/|$)|\/|([A-Za-z]:)?[/\\])/).test(x)) {
119 res = path.resolve(basedir, x);
120 if (x === '.' || x === '..' || x.slice(-1) === '/') res += '/';
121 if ((/\/$/).test(x) && res === basedir) {
122 loadAsDirectory(res, opts.package, onfile);
123 } else loadAsFile(res, opts.package, onfile);
124 } else if (includeCoreModules && isCore(x)) {
126 } else loadNodeModules(x, basedir, function (err, n, pkg) {
129 return maybeRealpath(realpath, n, opts, function (err, realN) {
133 cb(null, realN, pkg);
137 var moduleError = new Error("Cannot find module '" + x + "' from '" + parent + "'");
138 moduleError.code = 'MODULE_NOT_FOUND';
144 function onfile(err, m, pkg) {
146 else if (m) cb(null, m, pkg);
147 else loadAsDirectory(res, function (err, d, pkg) {
150 maybeRealpath(realpath, d, opts, function (err, realD) {
154 cb(null, realD, pkg);
158 var moduleError = new Error("Cannot find module '" + x + "' from '" + parent + "'");
159 moduleError.code = 'MODULE_NOT_FOUND';
165 function loadAsFile(x, thePackage, callback) {
166 var loadAsFilePackage = thePackage;
168 if (typeof loadAsFilePackage === 'function') {
169 cb = loadAsFilePackage;
170 loadAsFilePackage = undefined;
173 var exts = [''].concat(extensions);
174 load(exts, x, loadAsFilePackage);
176 function load(exts, x, loadPackage) {
177 if (exts.length === 0) return cb(null, undefined, loadPackage);
178 var file = x + exts[0];
180 var pkg = loadPackage;
181 if (pkg) onpkg(null, pkg);
182 else loadpkg(path.dirname(file), onpkg);
184 function onpkg(err, pkg_, dir) {
186 if (err) return cb(err);
187 if (dir && pkg && opts.pathFilter) {
188 var rfile = path.relative(dir, file);
189 var rel = rfile.slice(0, rfile.length - exts[0].length);
190 var r = opts.pathFilter(pkg, x, rel);
192 [''].concat(extensions.slice()),
193 path.resolve(dir, r),
199 function onex(err, ex) {
200 if (err) return cb(err);
201 if (ex) return cb(null, file, pkg);
202 load(exts.slice(1), x, pkg);
207 function loadpkg(dir, cb) {
208 if (dir === '' || dir === '/') return cb(null);
209 if (process.platform === 'win32' && (/^\w:[/\\]*$/).test(dir)) {
212 if ((/[/\\]node_modules[/\\]*$/).test(dir)) return cb(null);
214 maybeRealpath(realpath, dir, opts, function (unwrapErr, pkgdir) {
215 if (unwrapErr) return loadpkg(path.dirname(dir), cb);
216 var pkgfile = path.join(pkgdir, 'package.json');
217 isFile(pkgfile, function (err, ex) {
218 // on err, ex is false
219 if (!ex) return loadpkg(path.dirname(dir), cb);
221 readPackage(readFile, pkgfile, function (err, pkgParam) {
226 if (pkg && opts.packageFilter) {
227 pkg = opts.packageFilter(pkg, pkgfile);
235 function loadAsDirectory(x, loadAsDirectoryPackage, callback) {
237 var fpkg = loadAsDirectoryPackage;
238 if (typeof fpkg === 'function') {
243 maybeRealpath(realpath, x, opts, function (unwrapErr, pkgdir) {
244 if (unwrapErr) return cb(unwrapErr);
245 var pkgfile = path.join(pkgdir, 'package.json');
246 isFile(pkgfile, function (err, ex) {
247 if (err) return cb(err);
248 if (!ex) return loadAsFile(path.join(x, 'index'), fpkg, cb);
250 readPackage(readFile, pkgfile, function (err, pkgParam) {
251 if (err) return cb(err);
255 if (pkg && opts.packageFilter) {
256 pkg = opts.packageFilter(pkg, pkgfile);
259 if (pkg && pkg.main) {
260 if (typeof pkg.main !== 'string') {
261 var mainError = new TypeError('package “' + pkg.name + '” `main` must be a string');
262 mainError.code = 'INVALID_PACKAGE_MAIN';
263 return cb(mainError);
265 if (pkg.main === '.' || pkg.main === './') {
268 loadAsFile(path.resolve(x, pkg.main), pkg, function (err, m, pkg) {
269 if (err) return cb(err);
270 if (m) return cb(null, m, pkg);
271 if (!pkg) return loadAsFile(path.join(x, 'index'), pkg, cb);
273 var dir = path.resolve(x, pkg.main);
274 loadAsDirectory(dir, pkg, function (err, n, pkg) {
275 if (err) return cb(err);
276 if (n) return cb(null, n, pkg);
277 loadAsFile(path.join(x, 'index'), pkg, cb);
283 loadAsFile(path.join(x, '/index'), pkg, cb);
289 function processDirs(cb, dirs) {
290 if (dirs.length === 0) return cb(null, undefined);
293 isDirectory(path.dirname(dir), isdir);
295 function isdir(err, isdir) {
296 if (err) return cb(err);
297 if (!isdir) return processDirs(cb, dirs.slice(1));
298 loadAsFile(dir, opts.package, onfile);
301 function onfile(err, m, pkg) {
302 if (err) return cb(err);
303 if (m) return cb(null, m, pkg);
304 loadAsDirectory(dir, opts.package, ondir);
307 function ondir(err, n, pkg) {
308 if (err) return cb(err);
309 if (n) return cb(null, n, pkg);
310 processDirs(cb, dirs.slice(1));
313 function loadNodeModules(x, start, cb) {
314 var thunk = function () { return getPackageCandidates(x, start, opts); };
317 packageIterator ? packageIterator(x, start, thunk, opts) : thunk()