Tools: throw an error on duplication parameters in libraries

Tools/autotest/param_metadata/param.py

@@ -16,17 +16,24 @@ class Vehicle(object):
 
 
 class Library(object):
-    def __init__(self, name, reference=None, not_rst=False):
+    def __init__(self, name, reference=None, not_rst=False, check_duplicates=False):
         self.set_name(name)
         self.params = []
         if reference is not None:
             self.reference = reference
         self.not_rst = not_rst
+        self.check_duplicates = check_duplicates
 
     def set_name(self, name):
         self.name = name
         self.reference = name
 
+    def has_param(self, pname):
+        for p in self.params:
+            if pname == p.name:
+                return True
+        return False
+
 known_param_fields = [
              'Description',
              'DisplayName',

Tools/autotest/param_metadata/param_parse.py

@@ -90,7 +90,7 @@ def debug(str_to_print):
 
 def lua_applets():
     '''return list of Library objects for lua applets and drivers'''
-    lua_lib = Library("", reference="Lua Script", not_rst=True)
+    lua_lib = Library("", reference="Lua Script", not_rst=True, check_duplicates=True)
     patterns = ["libraries/AP_Scripting/applets/*.lua", "libraries/AP_Scripting/drivers/*.lua"]
     paths = []
     for p in patterns:
@@ -335,6 +335,9 @@ def process_library(vehicle, library, pathprefix=None):
                     continue
 
             p.path = path # Add path. Later deleted - only used for duplicates
+            if library.check_duplicates and library.has_param(p.name):
+                error("Duplicate parameter %s in %s" % (p.name, library.name))
+                continue
             library.params.append(p)
 
         group_matches = prog_groups.findall(p_text)