Refactor ropevim.py:_add_menu and add PopUp.Ropevim

Vim is not able to nest an already created menu under another menu.
This patch makes it easier to add the ropevim menu to multiple menus (for
example, the menubar and the popup menu).

ropevim.py

@@ -416,6 +416,36 @@ def __call__(self, arg_lead, cmd_line, cursor_pos):
 insert_shortcuts = {'code_assist': '<M-/>',
                     'lucky_assist': '<M-?>'}
 
+menu_structure = (
+    'open_project',
+    'close_project',
+    'find_file',
+    'undo',
+    'redo',
+    None, # separator
+    'rename',
+    'extract_variable',
+    'extract_method',
+    'inline',
+    'move',
+    'restructure',
+    'use_function',
+    'introduce_factory',
+    'change_signature',
+    'rename_current_module',
+    'move_current_module',
+    'module_to_package',
+    None, # separator
+    'code_assist',
+    'goto_definition',
+    'show_doc',
+    'find_occurrences',
+    'lucky_assist',
+    'jump_to_global',
+    'show_calltip',
+)
+
+
 def _init_variables():
     for variable, default in variables.items():
         vim.command('if !exists("g:%s")\n' % variable +
@@ -434,23 +464,21 @@ def _enable_shortcuts(env):
                         'endfunc')
             vim.command('imap %s <C-R>=%s()<cr>' % (shortcut, command_name))
 
-def _add_menu(env):
-    project = ['open_project', 'close_project', 'find_file', 'undo', 'redo']
-    refactor = ['rename', 'extract_variable', 'extract_method', 'inline',
-                'move', 'restructure', 'use_function', 'introduce_factory',
-                'change_signature', 'rename_current_module',
-                'move_current_module', 'module_to_package']
-    assists = ['code_assist', 'goto_definition', 'show_doc', 'find_occurrences',
-               'lucky_assist', 'jump_to_global', 'show_calltip']
-    vim.command('silent! aunmenu Ropevim')
-    for index, items in enumerate([project, assists, refactor]):
-        if index != 0:
-            vim.command('amenu <silent> &Ropevim.-SEP%s- :' % index)
-        for name in items:
-            item = '\ '.join(token.title() for token in name.split('_'))
-            for command in ['amenu', 'vmenu']:
-                vim.command('%s <silent> &Ropevim.%s :call %s()<cr>' %
-                            (command, item, _vim_name(name)))
+def _add_menu(env, root_node='&Ropevim'):
+    cmd_tmpl = '%s <silent> %s.%s :call %s()<cr>'
+
+    vim.command('silent! aunmenu %s' % root_node)
+
+    for i, cb in enumerate(menu_structure):
+        if cb is None:
+            vim.command('amenu <silent> %s.-SEP%s- :' % (root_node, i))
+            continue
+
+        # use_function -> Use\ Function
+        name = cb.replace('_', '\ ').title()
+
+        for cmd in ('amenu', 'vmenu'):
+            vim.command(cmd_tmpl % (cmd, root_node, name, _vim_name(cb)))
 
 
 ropemode.decorators.logger.message = echo
@@ -462,4 +490,6 @@ def _add_menu(env):
 _interface = ropemode.interface.RopeMode(env=_env)
 _interface.init()
 _enable_shortcuts(_env)
+
 _add_menu(_env)
+_add_menu(_env, 'PopUp.&Ropevim') # menu weight can also be added