Protection for empty directory string when loading python Refs #5920

Code/Mantid/Framework/PythonInterface/mantid/__init__.py

@@ -85,7 +85,12 @@ def apiVersion():
 plugin_dirs = kernel.config['pythonalgorithms.directories'].split(";")
 plugin_files = []
 for directory in plugin_dirs:
-    plugin_files += _plugins.find_plugins(directory)
+    try:
+        if directory != '':
+            plugin_files += _plugins.find_plugins(directory)
+    except ValueError, exc:
+        logger.warning(str(exc))
+        continue
 
 # Mockup the full API first so that any Python algorithm module has something to import
 _simpleapi.mockup(plugin_files)

Code/Mantid/Framework/PythonInterface/mantid/kernel/plugins.py

@@ -40,9 +40,10 @@ def run(self):
 def find_plugins(top_dir):
     """
        Searches recursively from the given directory to find the list of plugins that should be loaded
+       @param top_dir :: A string containing a path to a directory. Throws ValueError if it is not valid
     """
     if not _os.path.isdir(top_dir):
-        raise ValueError("Cannot search given path for plugins, path is not a directory: %s " % str(top_dir))
+        raise ValueError("Cannot search given path for plugins, path is not a directory: '%s' " % str(top_dir))
     plugins = []
     for root, dirs, files in _os.walk(top_dir):
         for f in files: