View can use any printer, except when pretty_print() is called.

Moreover, make print_todo of PrettyPrinter have the same signature as
the Printer class. Clients must use add_filter to specify any additional
filters when printing.

The Command class holds a PrettyPrinter instance (rather than a generic
printer). This means that add_filter is called, all future invocations
of print_todo will apply these filters. This is not always desired, so
in those cases a subcommand should instantiate its own printer (this
happens for instance at the DoCommand).

topydo/lib/AddCommand.py

@@ -93,9 +93,8 @@ class AddCommand(Command):
             self.todo = self.todolist.add(self.text)
             self._postprocess_input_todo()
 
-            self.out(
-                self.printer.print_todo(self.todo,
-                [PrettyPrinterNumbers(self.todolist)]))
+            self.printer.add_filter(PrettyPrinterNumbers(self.todolist))
+            self.out(self.printer.print_todo(self.todo))
         else:
             self.error(self.usage())
 

topydo/lib/AppendCommand.py

@@ -38,8 +38,8 @@ class AppendCommand(Command):
                 todo = self.todolist.todo(number)
                 self.todolist.append(todo, text)
 
-                self.out(self.printer.print_todo(todo,
-                    [PrettyPrinterNumbers(self.todolist)]))
+                self.printer.add_filter(PrettyPrinterNumbers(self.todolist))
+                self.out(self.printer.print_todo(todo))
             else:
                 self.error(self.usage())
         except InvalidCommandArgument:

topydo/lib/DCommand.py

@@ -17,6 +17,7 @@
 import re
 
 from topydo.lib.Command import Command
+from topydo.lib.PrettyPrinter import PrettyPrinter
 from topydo.lib.PrettyPrinterFilter import PrettyPrinterNumbers
 from topydo.lib.TodoListBase import InvalidTodoException
 
@@ -72,8 +73,9 @@ class DCommand(Command):
         )
 
     def _print_list(self, p_todos):
-        filters = [PrettyPrinterNumbers(self.todolist)]
-        self.out("\n".join(self.printer.print_list(p_todos, filters)))
+        printer = PrettyPrinter()
+        printer.add_filter(PrettyPrinterNumbers(self.todolist))
+        self.out("\n".join(printer.print_list(p_todos)))
 
     def prompt_text(self):
         return "Yes or no? [y/N] "

topydo/lib/DepCommand.py

@@ -97,7 +97,8 @@ class DepCommand(Command):
             if todos:
                 sorter = Sorter(config().sort_string())
                 instance_filter = Filter.InstanceFilter(todos)
-                view = View(sorter, [instance_filter], self.todolist)
+                view = View(sorter, [instance_filter], self.todolist,
+                    self.printer)
                 self.out(view.pretty_print())
         except InvalidTodoException:
             self.error("Invalid todo number given.")

topydo/lib/DoCommand.py

@@ -17,6 +17,7 @@
 from datetime import date
 
 from topydo.lib.DCommand import DCommand
+from topydo.lib.PrettyPrinter import PrettyPrinter
 from topydo.lib.PrettyPrinterFilter import PrettyPrinterNumbers
 from topydo.lib.Recurrence import advance_recurring_todo, strict_advance_recurring_todo
 from topydo.lib.Utils import date_string_to_date
@@ -56,8 +57,10 @@ class DoCommand(DCommand):
                     self.completion_date)
 
             self.todolist.add_todo(new_todo)
-            self.out(self.printer.print_todo(new_todo,
-                [PrettyPrinterNumbers(self.todolist)]))
+
+            printer = PrettyPrinter()
+            printer.add_filter(PrettyPrinterNumbers(self.todolist))
+            self.out(printer.print_todo(new_todo))
 
     def prompt_text(self):
         return "Also mark subtasks as done? [y/N] "
@@ -78,7 +81,9 @@ class DoCommand(DCommand):
         """ Actions specific to this command. """
         self._handle_recurrence(p_todo)
         self.execute_specific_core(p_todo)
-        self.out(self.prefix() + self.printer.print_todo(p_todo))
+
+        printer = PrettyPrinter()
+        self.out(self.prefix() + printer.print_todo(p_todo))
 
     def execute_specific_core(self, p_todo):
         """

topydo/lib/ListCommand.py

@@ -21,6 +21,7 @@ from topydo.lib.Config import config
 from topydo.lib import Filter
 from topydo.lib.PrettyPrinterFilter import PrettyPrinterIndentFilter
 from topydo.lib.Sorter import Sorter
+from topydo.lib.View import View
 
 class ListCommand(Command):
     def __init__(self, p_args, p_todolist,
@@ -74,18 +75,23 @@ class ListCommand(Command):
 
         return filters
 
-    def execute(self):
-        if not super(ListCommand, self).execute():
-            return False
-
-        self._process_flags()
+    def _print(self):
+        """ Prints the todos. """
 
         sorter = Sorter(self.sort_expression)
         filters = self._filters()
 
+        view = View(sorter, filters, self.todolist)
+
         indent = config().list_indent()
-        pp_filters = [PrettyPrinterIndentFilter(indent)]
-        self.out(self.todolist.view(sorter, filters).pretty_print(pp_filters))
+        self.out(view.pretty_print([PrettyPrinterIndentFilter(indent)]))
+
+    def execute(self):
+        if not super(ListCommand, self).execute():
+            return False
+
+        self._process_flags()
+        self._print()
 
     def usage(self):
         return """Synopsis: ls [-x] [-s <sort_expression>] [expression]"""

topydo/lib/PostponeCommand.py

@@ -75,8 +75,8 @@ class PostponeCommand(Command):
                 todo.set_tag(config().tag_due(), new_due.isoformat())
 
                 self.todolist.set_dirty()
-                self.out(self.printer.print_todo(todo,
-                    [PrettyPrinterNumbers(self.todolist)]))
+                self.printer.add_filter(PrettyPrinterNumbers(self.todolist))
+                self.out(self.printer.print_todo(todo))
             else:
                 self.error("Invalid date pattern given.")
 

topydo/lib/PrettyPrinter.py

@@ -40,28 +40,26 @@ class PrettyPrinter(Printer):
     add colors, indentation, etc. These filters are found in the
     PrettyPrinterFilter module.
     """
-    def print_todo(self, p_todo, p_filters=None):
+    def __init__(self):
         """
-        Given a todo item, pretty print it.
+        Constructor.
+        """
+        super(PrettyPrinter, self).__init__()
+        self.filters = []
+
+    def add_filter(self, p_filter):
+        """
+        Adds a filter to be applied when calling print_todo.
 
-        p_filters is a list of PrettyPrinterFilter objects (typically
-        subclasses of it, see PrettyPrinterFilter module)
+        p_filter is an instance of a PrettyPrinterFilter.
         """
-        p_filters = p_filters or []
+        self.filters.append(p_filter)
 
+    def print_todo(self, p_todo):
+        """ Given a todo item, pretty print it. """
         todo_str = str(p_todo)
 
-        for ppf in p_filters:
+        for ppf in self.filters:
             todo_str = ppf.filter(todo_str, p_todo)
 
         return todo_str
-
-    def print_list(self, p_todos, p_filters=None):
-        """
-        Given a list of todo items, pretty print it and return a list of
-        formatted strings.
-
-        This override also passes on filters.
-        """
-        p_filters = p_filters or []
-        return [self.print_todo(todo, p_filters) for todo in p_todos]

topydo/lib/TagCommand.py

@@ -60,8 +60,8 @@ class TagCommand(Command):
             self.value = ""
 
     def _print(self):
-        filters = [PrettyPrinterNumbers(self.todolist)]
-        self.out(self.printer.print_todo(self.todo, filters))
+        self.printer.add_filter(PrettyPrinterNumbers(self.todolist))
+        self.out(self.printer.print_todo(self.todo))
 
     def _choose(self):
         """

topydo/lib/View.py

@@ -27,13 +27,18 @@ class View(object):
     A view is instantiated by a todo list, usually obtained from a todo.txt
     file. Also a sorter and a list of filters should be given that is applied
     to the list.
+
+    A printer can be passed, but it won't be used when pretty_print() is
+    called, since it will instantiate its own pretty printer instance.
     """
-    def __init__(self, p_sorter, p_filters, p_todolist):
+    def __init__(self, p_sorter, p_filters, p_todolist,
+            p_printer=PrettyPrinter()):
+
         self._todolist = p_todolist
         self._viewdata = []
         self._sorter = p_sorter
         self._filters = p_filters
-        self._printer = PrettyPrinter()
+        self._printer = p_printer
 
         self.update()
 
@@ -51,13 +56,15 @@ class View(object):
         """ Pretty prints the view. """
         p_pp_filters = p_pp_filters or []
 
-        pp_filters = [
-            PrettyPrinterNumbers(self._todolist),
-            PrettyPrinterColorFilter()
-        ]
-        pp_filters += p_pp_filters
+        # since we're using filters, always use PrettyPrinter
+        printer = PrettyPrinter()
+        printer.add_filter(PrettyPrinterNumbers(self._todolist))
+        printer.add_filter(PrettyPrinterColorFilter())
+
+        for ppf in p_pp_filters:
+            printer.add_filter(ppf)
 
-        return '\n'.join(self._printer.print_list(self._viewdata, pp_filters))
+        return '\n'.join(printer.print_list(self._viewdata))
 
     def __str__(self):
         return '\n'.join(self._printer.print_list(self._viewdata))