Use stat instead of lstat when checking CWD

This allows CWD to be a symbolic link. Fixes #204

Fix #204
Fix #214

Edit: added test, added support for sync case -- @isaacs

Author: stkb

lib/mkdir.js

@@ -69,7 +69,7 @@ const mkdir = module.exports = (dir, opt, cb) => {
     return done()
 
   if (dir === cwd)
-    return fs.lstat(dir, (er, st) => {
+    return fs.stat(dir, (er, st) => {
       if (er || !st.isDirectory())
         er = new CwdError(dir, er && er.code || 'ENOTDIR')
       done(er)
@@ -154,7 +154,7 @@ const mkdirSync = module.exports.sync = (dir, opt) => {
     let ok = false
     let code = 'ENOTDIR'
     try {
-      ok = fs.lstatSync(dir).isDirectory()
+      ok = fs.statSync(dir).isDirectory()
     } catch (er) {
       code = er.code
     } finally {

test/unpack.js

@@ -79,9 +79,12 @@ t.test('basic file unpack tests', t => {
     t.test(tarfile, t => {
       const tf = path.resolve(tars, tarfile)
       const dir = path.resolve(basedir, tarfile)
+      const linkdir = path.resolve(basedir, tarfile + '.link')
       t.beforeEach(cb => {
         rimraf.sync(dir)
+        rimraf.sync(linkdir)
         mkdirp.sync(dir)
+        fs.symlinkSync(dir, linkdir)
         cb()
       })
 
@@ -99,12 +102,12 @@ t.test('basic file unpack tests', t => {
       t.test('async unpack', t => {
         t.plan(2)
         t.test('strict', t => {
-          const unpack = new Unpack({ cwd: dir, strict: true })
+          const unpack = new Unpack({ cwd: linkdir, strict: true })
           fs.createReadStream(tf).pipe(unpack)
           eos(unpack, _ => check(t))
         })
         t.test('loose', t => {
-          const unpack = new Unpack({ cwd: dir })
+          const unpack = new Unpack({ cwd: linkdir })
           fs.createReadStream(tf).pipe(unpack)
           eos(unpack, _ => check(t))
         })
@@ -113,12 +116,12 @@ t.test('basic file unpack tests', t => {
       t.test('sync unpack', t => {
         t.plan(2)
         t.test('strict', t => {
-          const unpack = new UnpackSync({ cwd: dir })
+          const unpack = new UnpackSync({ cwd: linkdir })
           unpack.end(fs.readFileSync(tf))
           check(t)
         })
         t.test('loose', t => {
-          const unpack = new UnpackSync({ cwd: dir })
+          const unpack = new UnpackSync({ cwd: linkdir })
           unpack.end(fs.readFileSync(tf))
           check(t)
         })