Let TodoList provide a pretty printer filter for todo numbers.

A step towards elimating knowledge of the todo list in the items itself.

AddCommand.py

@@ -5,7 +5,7 @@ import re
 
 import Config
 import Command
-from PrettyPrinter import pretty_print, pp_number
+from PrettyPrinter import pretty_print
 from RelativeDate import relative_date_to_date
 
 class AddCommand(Command.Command):
@@ -70,4 +70,4 @@ class AddCommand(Command.Command):
         self.todo = self.todolist.add(self.text)
         self._postprocess_input_todo()
 
-        self.out(pretty_print(self.todo, [pp_number]))
+        self.out(pretty_print(self.todo, [self.todolist.pp_number()]))

AppendCommand.py

 import Command
-from PrettyPrinter import pretty_print, pp_number
+from PrettyPrinter import pretty_print
 from Utils import convert_todo_number
 
 class AppendCommand(Command.Command):
@@ -15,4 +15,4 @@ class AppendCommand(Command.Command):
 
         self.todolist.append(number, text)
 
-        self.out(pretty_print(self.todo, [pp_number]))
+        self.out(pretty_print(self.todo, [self.todolist.pp_number]))

DoCommand.py

@@ -17,20 +17,20 @@ class DoCommand(Command.Command):
     def _complete_children(self):
             children = [t for t in self.todolist.children(self.number) if not t.is_completed()]
             if children:
-                self.out("\n".join(pretty_print_list(children, [pp_number])))
+                self.out("\n".join(pretty_print_list(children, [self.todolist.pp_number()])))
 
                 confirmation = self.prompt("Also mark subtasks as done? [n] ")
 
                 if re.match('^y(es)?$', confirmation, re.I):
                     for child in children:
                         self.todolist.set_todo_completed(child)
-                        self.out(pretty_print(child, [pp_number]))
+                        self.out(pretty_print(child, [self.todolist.pp_number()]))
 
     def _handle_recurrence(self):
         if self.todo.has_tag('rec'):
             new_todo = advance_recurring_todo(self.todo)
             self.todolist.add_todo(new_todo)
-            self.out(pretty_print(new_todo, [pp_number]))
+            self.out(pretty_print(new_todo, [self.todolist.pp_number()]))
 
     def execute(self):
         if self.todo and not self.todo.is_completed():

PrettyPrinter.py

@@ -37,14 +37,6 @@ def pp_color(p_todo_str, p_todo):
 
     return p_todo_str
 
-def pp_number(p_todo_str, p_todo):
-    """
-    Inserts the todo number at the start of the string.
-
-    Should be passed as a filter in the filter list of pretty_print()
-    """
-    return "%3d %s" % (p_todo.attributes['number'], p_todo_str)
-
 def pretty_print(p_todo, p_filters=[]):
     """
     Given a todo item, pretty print it and return a list of formatted strings.
@@ -55,7 +47,7 @@ def pretty_print(p_todo, p_filters=[]):
     * the todo's text that has to be modified;
     * the todo object itself which allows for obtaining relevant information.
 
-    Examples are pp_color and pp_number in this file.
+    Example is pp_color in this fle.
     """
 
     todo_str = str(p_todo)

TodoList.py

@@ -170,7 +170,7 @@ class TodoList(object):
         defined by the end user. Todos is this list should not be modified,
         modifications should occur through this class.
         """
-        return View.View(p_sorter, p_filters, self._todos)
+        return View.View(p_sorter, p_filters, self)
 
     def add_dependency(self, p_number1, p_number2):
         """ Adds a dependency from task 1 to task 2. """
@@ -293,6 +293,13 @@ class TodoList(object):
     def number(self, p_todo):
         return p_todo.attributes['number'] # TODO: do the lookup
 
+    def pp_number(self):
+        """
+        A filter for the pretty printer to append the todo number to the
+        printed todo.
+        """
+        return lambda p_todo_str, p_todo: "%3d %s" % (self.number(p_todo), p_todo_str)
+
     def __str__(self):
         return '\n'.join(pretty_print_list(self._todos))
 

View.py

 """ A view is a list of todos, sorted and filtered. """
 
-from PrettyPrinter import *
+from PrettyPrinter import pretty_print_list, pp_color
 
 class View(object):
     """
@@ -8,8 +8,8 @@ class View(object):
     file. Also a sorter and a list of filters should be given that is applied
     to the list.
     """
-    def __init__(self, p_sorter, p_filters, p_todos):
-        self._todos = p_todos
+    def __init__(self, p_sorter, p_filters, p_todolist):
+        self._todolist = p_todolist
         self._viewdata = []
         self._sorter = p_sorter
         self._filters = p_filters
@@ -21,14 +21,15 @@ class View(object):
         Updates the view data. Should be called when the backing todo list
         has changed.
         """
-        self._viewdata = self._sorter.sort(self._todos)
+        self._viewdata = self._sorter.sort(self._todolist.todos())
 
         for _filter in self._filters:
             self._viewdata = _filter.filter(self._viewdata)
 
     def pretty_print(self):
         """ Pretty prints the view. """
-        return '\n'.join(pretty_print_list(self._viewdata, [pp_number, pp_color]))
+        pp_filters = [self._todolist.pp_number(), pp_color];
+        return '\n'.join(pretty_print_list(self._viewdata, pp_filters))
 
     def __str__(self):
         return '\n'.join(pretty_print_list(self._viewdata))