test: test sync version of mkdir & rmdir

This patch includes tests for sync versions of mkdir and rmdir.
Also, it moves the test to `parallel`.

PR-URL: #2588
Reviewed-By: Roman Reiss <me@silverwind.io>
Reviewed-By: Johan Bergström <bugs@bergstroem.nu>

test/parallel/test-fs-mkdir-rmdir.js

@@ -0,0 +1,37 @@
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const path = require('path');
+const fs = require('fs');
+const d = path.join(common.tmpDir, 'dir');
+
+common.refreshTmpDir();
+
+// Make sure the directory does not exist
+assert(!common.fileExists(d));
+// Create the directory now
+fs.mkdirSync(d);
+// Make sure the directory exists
+assert(common.fileExists(d));
+// Try creating again, it should fail with EEXIST
+assert.throws(function() {
+  fs.mkdirSync(d);
+}, /EEXIST: file already exists, mkdir/);
+// Remove the directory now
+fs.rmdirSync(d);
+// Make sure the directory does not exist
+assert(!common.fileExists(d));
+
+// Similarly test the Async version
+fs.mkdir(d, 0o666, function(err) {
+  assert.ifError(err);
+
+  fs.mkdir(d, 0o666, function(err) {
+    assert.ok(err.message.match(/^EEXIST/), 'got EEXIST message');
+    assert.equal(err.code, 'EEXIST', 'got EEXIST code');
+    assert.equal(err.path, d, 'got proper path for EEXIST');
+
+    fs.rmdir(d, assert.ifError);
+  });
+});