Move priority to its own Command class.

Main.py

 #!/usr/bin/env python
 """ Entry file for the Python todo.txt CLI. """
 
-import re
 import sys
 
 from AddCommand import AddCommand
 from AppendCommand import AppendCommand
 from DepCommand import DepCommand
-from DoCommand import DoCommand
 import Config
+from DoCommand import DoCommand
 import Filter
 from PrettyPrinter import pretty_print
+from PriorityCommand import PriorityCommand
 import Sorter
 import TodoFile
 import TodoList
@@ -82,21 +82,8 @@ class Application(object): # TODO: rename to CLIApplication
         command.execute()
 
     def pri(self):
-        number = convert_todo_number(argument(2))
-        priority = argument(3)
-
-        if re.match('^[A-Z]$', priority):
-            todo = self.todolist.todo(number)
-
-            if todo:
-                old_priority = todo.priority()
-                todo.set_priority(priority)
-
-                print "Priority changed from %s to %s" \
-                    % (old_priority, priority)
-                self.print_todo(number)
-        else:
-            error("Invalid priority given.")
+        command = PriorityCommand(arguments(), self.todolist)
+        command.execute()
 
     def list(self):
         sorter = Sorter.Sorter(Config.SORT_STRING)

PriorityCommand.py

+import re
+
+import Command
+from Utils import convert_todo_number
+
+class PriorityCommand(Command.Command):
+    def __init__(self, p_args, p_todolist):
+        super(PriorityCommand, self).__init__(p_args, p_todolist)
+        self.number = convert_todo_number(self.argument(0))
+        self.todo = self.todolist.todo(self.number)
+        self.priority = self.argument(1)
+
+    def execute(self):
+        if re.match('^[A-Z]$', self.priority):
+            old_priority = self.todo.priority()
+            self.todolist.set_priority(self.number, self.priority)
+
+            print "Priority changed from %s to %s" \
+                % (old_priority, self.priority) # FIXME
+            # self.print_todo(number) # FIXME
+        else:
+            # error("Invalid priority given.") # TODO
+            pass