Update helper to use Path in get_script_path and get_reference_paths.

modules/plugin_dbui/helper.py

 """ a series of helper functions
 
 """
-import os
 import re
-import subprocess
 
 
 from .constant import INLINE_ALERT
@@ -485,10 +483,12 @@ def get_reference_paths():
             ``("applications/myapp", "/myapp")``
 
     """
-    server_path = os.path.join("applications", current.request.application)
-    client_path = os.path.join(os.path.sep, current.request.application)
+    application = current.request.application
+
+    server_path = Path("applications", application)
+    client_path = Path("/", application)
 
-    return (server_path, client_path)
+    return (str(server_path), str(client_path))
 
 
 def get_set_field(field):
@@ -541,32 +541,32 @@ def get_script_path(plugin):
 
     Returns:
         str:
-            the local path of the script file relative to the
-            application directory.
+            * absolute path with respect to the application
+            * for example /myapp/blabla.
 
     """
-    server_path, client_path = get_reference_paths()
+    application = current.request.application
+    app_path = Path("applications", application)
 
     # script name specifies in the URL
     if "script" in current.request.vars:
         script = current.request.vars.script
 
         if not script.endswith(".js"):
-            script = "%s.js" % script
-
-        pdir = os.path.join(server_path, plugin.app_script_dir)
+            script = f"{script}.js"
 
-        if script not in os.listdir(pdir):
-            raise HTTP(500, 'Request script "%s" does not exist !!!' % script)
+        pscript = app_path / plugin.app_script_dir / script
+        if not pscript.exists():
+            raise HTTP(500, f"Request script '{script}' does not exist !!!")
 
-        return os.path.join(client_path, plugin.app_script_dir, script)
+        return str(Path("/", application, plugin.app_script_dir, script))
 
     # default script for the application
     if plugin.app_script:
-        return os.path.join(client_path, plugin.app_script)
+        return str(Path("/", application, plugin.app_script))
 
     # default script for the plugin
-    return os.path.join(client_path, plugin.dbui_script)
+    return str(Path("/", application, plugin.dbui_script))
 
 
 def get_store_id(name):