Add path.sep for older versions of Node.js.

Former-commit-id: 1a058681fc5c6aae426902a7d6dd76b3a5849837

build/mkdirp-sync.js

@@ -6,6 +6,11 @@
   var fs = require('fs'),
       path = require('path');
 
+  /** Add `path.sep` for older versions of Node.js */
+  path.sep || (path.sep = process.platform == 'win32' ? '\\' : '/');
+
+  /*--------------------------------------------------------------------------*/
+
   /**
    * Makes the given `path` directory, without throwing errors for existing
    * directories and making parent directories as needed.
@@ -36,6 +41,8 @@
     });
   }
 
+  /*--------------------------------------------------------------------------*/
+
   // expose
   module.exports = mkdirpSync;
 }());