def normalize_tags(contents, is_stable_tag=lambda tag: False):
"""Normalize open and close tags to ensure proper nesting
This is especially useful for saving to HTML
is_stable_tag -- a function that returns True iff a tag should not
be touched (``stable'').
NOTE: All iterators will be turned to None's. Since were are changing
tag order, iterators no longer make sense
NOTE: assumes we do not have any 'beginstr' and 'endstr' items
"""
open_stack = []
contents = PushIter(contents)
for item in contents:
kind, it, param = item
if kind == "begin":
if is_stable_tag(param):
# if stable tag, skim ahead to see its closing tag
stable_span = LinkedList()
within_closes = set()
for item2 in contents:
stable_span.append(item2)
if item2[0] == "end":
# look at closing tags
if item2[2] == param:
# found matching stable close
break
else:
# record tags that close within the stable_span
within_closes.add(item2[2])
# push items back on contents stream
for item2 in reversed(stable_span):
contents.push(item2)
# define tag classes
# preopen = open_stack
# preopen_inside = preopen's with a close in stable_span
preopen_inside = []
for tag in open_stack:
if tag in within_closes:
preopen_inside.append(tag)
# close preopen_inside
for item2 in _normalize_close(open_stack, preopen_inside):
yield item2
# yield stable open
open_stack.append(param)
yield ("begin", None, param)
# reopen preopen_inside
for tag in preopen_inside:
open_stack.append(tag)
yield ("begin", None, tag)
else:
# yield item unchanged
open_stack.append(param)
yield ("begin", None, param)
elif kind == "end":
for item2 in _normalize_close(open_stack, [param]):
yield item2
else:
yield (kind, None, param)
class UndoStack(object):
"""UndoStack for maintaining undo and redo actions"""
def __init__(self, maxsize=sys.maxint):
"""maxsize -- maximum size of undo list"""
# stacks maintaining (undo,redo) pairs
self._undo_actions = LinkedList()
self._redo_actions = []
# grouping several actions into one
self._group_counter = 0
self._pending_actions = []
# suppress undo/redo while counter > 0
self._suppress_counter = 0
# maximum size undo stack
self._maxsize = maxsize
self._in_progress = False
def do(self, action, undo, execute=True):
"""Perform action() (if execute=True) and place (action,undo) pair
on stack"""
if self._suppress_counter > 0:
return
if self._group_counter == 0:
# grouping is not active, push action pair and clear redo stack
self._undo_actions.append((action, undo))
self._redo_actions = []
# TODO: should stack be suppressed at this time?
if execute:
action()
# maintain proper undo size
while len(self._undo_actions) > self._maxsize:
self._undo_actions.pop_front()
else:
# grouping is active, place action pair on pending stack
self._pending_actions.append((action, undo))
self._redo_actions = []
if execute:
action()
def undo(self):
"""Undo last action on stack"""
assert self._group_counter == 0
if len(self._undo_actions) > 0:
action, undo = self._undo_actions.pop()
self.suppress()
self._in_progress = True
undo()
self._in_progress = False
self.resume()
self._redo_actions.append((action, undo))
def redo(self):
"""Redo last action on stack"""
assert self._group_counter == 0
if len(self._redo_actions) > 0:
action, undo = self._redo_actions.pop()
self.suppress()
self._in_progress = True
action()
self._in_progress = False
self.resume()
self._undo_actions.append((action, undo))
while len(self._undo_actions) > self._maxsize:
self._undo_actions.pop_front()
def begin_action(self):
"""Start grouping actions
Can be called recursively. Must have corresponding end_action() call
"""
self._group_counter += 1
def end_action(self):
"""Stop grouping actions
Can be called recursively.
"""
self._group_counter -= 1
assert self._group_counter >= 0
if self._group_counter == 0:
if len(self._pending_actions) > 0:
actions, undos = zip(*self._pending_actions)
self._undo_actions.append(
(cat_funcs(actions), cat_funcs(reversed(undos))))
self._pending_actions = []
while len(self._undo_actions) > self._maxsize:
self._undo_actions.pop_front()
def abort_action(self):
"""
Stop grouping actions and throw away actions collected so far
"""
self._group_counter = 0
self._pending_actions = []
def suppress(self):
"""Suppress pushing actions on stack
Can be called recursively. Must have corresponding resume() call"""
self._suppress_counter += 1
def resume(self):
"""Resume pushing actions on stack
Can be called recursively.
"""
self._suppress_counter -= 1
assert self._suppress_counter >= 0
def is_suppressed(self):
"""Returns True if UndoStack is being suprressed"""
return self._suppress_counter > 0
def reset(self):
"""Clear UndoStack of all actions"""
self._undo_actions.clear()
self._redo_actions = []
self._group_counter = 0
self._pending_actions = []
self._suppress_counter = 0
def is_in_progress(self):
"""Returns True if undo or redo is in progress"""
return self._in_progress
def normalize_tags(contents, is_stable_tag=lambda tag: False):
"""Normalize open and close tags to ensure proper nesting
This is especially useful for saving to HTML
is_stable_tag -- a function that returns True iff a tag should not
be touched (``stable'').
NOTE: All iterators will be turned to None's. Since were are changing
tag order, iterators no longer make sense
NOTE: assumes we do not have any 'beginstr' and 'endstr' items
"""
open_stack = []
contents = PushIter(contents)
for item in contents:
kind, it, param = item
if kind == "begin":
if is_stable_tag(param):
# if stable tag, skim ahead to see its closing tag
stable_span = LinkedList()
within_closes = set()
for item2 in contents:
stable_span.append(item2)
if item2[0] == "end":
# look at closing tags
if item2[2] == param:
# found matching stable close
break
else:
# record tags that close within the stable_span
within_closes.add(item2[2])
# push items back on contents stream
for item2 in reversed(stable_span):
contents.push(item2)
# define tag classes
# preopen = open_stack
# preopen_inside = preopen's with a close in stable_span
preopen_inside = []
for tag in open_stack:
if tag in within_closes:
preopen_inside.append(tag)
# close preopen_inside
for item2 in _normalize_close(open_stack, preopen_inside):
yield item2
# yield stable open
open_stack.append(param)
yield ("begin", None, param)
# reopen preopen_inside
for tag in preopen_inside:
open_stack.append(tag)
yield ("begin", None, tag)
else:
# yield item unchanged
open_stack.append(param)
yield ("begin", None, param)
elif kind == "end":
for item2 in _normalize_close(open_stack, [param]):
yield item2
else:
yield (kind, None, param)
class UndoStack(object):
"""UndoStack for maintaining undo and redo actions"""
def __init__(self, maxsize=sys.maxint):
"""maxsize -- maximum size of undo list"""
# stacks maintaining (undo,redo) pairs
self._undo_actions = LinkedList()
self._redo_actions = []
# grouping several actions into one
self._group_counter = 0
self._pending_actions = []
# suppress undo/redo while counter > 0
self._suppress_counter = 0
# maximum size undo stack
self._maxsize = maxsize
self._in_progress = False
def do(self, action, undo, execute=True):
"""Perform action() (if execute=True) and place (action,undo) pair
on stack"""
if self._suppress_counter > 0:
return
if self._group_counter == 0:
# grouping is not active, push action pair and clear redo stack
self._undo_actions.append((action, undo))
self._redo_actions = []
# TODO: should stack be suppressed at this time?
if execute:
action()
# maintain proper undo size
while len(self._undo_actions) > self._maxsize:
self._undo_actions.pop_front()
else:
# grouping is active, place action pair on pending stack
self._pending_actions.append((action, undo))
self._redo_actions = []
if execute:
action()
def undo(self):
"""Undo last action on stack"""
assert self._group_counter == 0
if len(self._undo_actions) > 0:
action, undo = self._undo_actions.pop()
self.suppress()
self._in_progress = True
undo()
self._in_progress = False
self.resume()
self._redo_actions.append((action, undo))
def redo(self):
"""Redo last action on stack"""
assert self._group_counter == 0
if len(self._redo_actions) > 0:
action, undo = self._redo_actions.pop()
self.suppress()
self._in_progress = True
action()
self._in_progress = False
self.resume()
self._undo_actions.append((action, undo))
while len(self._undo_actions) > self._maxsize:
self._undo_actions.pop_front()
def begin_action(self):
"""Start grouping actions
Can be called recursively. Must have corresponding end_action() call
"""
self._group_counter += 1
def end_action(self):
"""Stop grouping actions
Can be called recursively.
"""
self._group_counter -= 1
assert self._group_counter >= 0
if self._group_counter == 0:
if len(self._pending_actions) > 0:
actions, undos = zip(*self._pending_actions)
self._undo_actions.append((cat_funcs(actions), cat_funcs(reversed(undos))))
self._pending_actions = []
while len(self._undo_actions) > self._maxsize:
self._undo_actions.pop_front()
def abort_action(self):
"""
Stop grouping actions and throw away actions collected so far
"""
self._group_counter = 0
self._pending_actions = []
def suppress(self):
"""Suppress pushing actions on stack
Can be called recursively. Must have corresponding resume() call"""
self._suppress_counter += 1
def resume(self):
"""Resume pushing actions on stack
Can be called recursively.
"""
self._suppress_counter -= 1
assert self._suppress_counter >= 0
def is_suppressed(self):
"""Returns True if UndoStack is being suprressed"""
return self._suppress_counter > 0
def reset(self):
"""Clear UndoStack of all actions"""
self._undo_actions.clear()
self._redo_actions = []
self._group_counter = 0
self._pending_actions = []
self._suppress_counter = 0
def is_in_progress(self):
"""Returns True if undo or redo is in progress"""
return self._in_progress