[Fix] properly handle paths with a trailing slash

.gitignore

@@ -0,0 +1,2 @@
+node_modules
+npm-debug.log

lib/async.js

@@ -32,7 +32,7 @@ module.exports = function resolve (x, opts, cb) {
 
     if (/^(?:\.\.?(?:\/|$)|\/|([A-Za-z]:)?[\\\/])/.test(x)) {
         var res = path.resolve(y, x);
-        if (x === '..') res += '/';
+        if (x === '..' || x[x.length-1] === '/') res += path.sep;
         loadAsFile(res, function (err, m, pkg) {
             if (err) cb(err)
             else if (m) cb(null, m, pkg)

lib/sync.js

@@ -20,7 +20,7 @@ module.exports = function (x, opts) {
 
     if (/^(?:\.\.?(?:\/|$)|\/|([A-Za-z]:)?[\\\/])/.test(x)) {
         var res = path.resolve(y, x);
-        if (x === '..') res += '/';
+        if (x === '..' || x[x.length-1] === '/') res += path.sep;
         var m = loadAsFileSync(res) || loadAsDirectorySync(res);
         if (m) return m;
     } else {

test/issue51.js

@@ -0,0 +1,12 @@
+var test = require('tap').test;
+var resolve = require('../');
+var path = require('path')
+
+test('issue 51', function (t) {
+    t.ok(resolve.sync('./issue51/test/') === path.resolve(__dirname, 'issue51/test/index.js'));
+    resolve('./issue51/test/', function(e, result) {
+        if(e) throw e
+        t.ok(result === path.resolve(__dirname, 'issue51/test/index.js'));
+        t.end();
+    })
+});

test/issue51/moo.js

@@ -0,0 +1 @@
+require('./test/')

test/issue51/test.js

@@ -0,0 +1 @@
+console.log('file')

test/issue51/test/index.js

@@ -0,0 +1 @@
+console.log('folder')