X-Git-Url: https://git.madduck.net/etc/taskwarrior.git/blobdiff_plain/11ffa3d5433c690448add06638f96c42fff262de..0531935967fd784f762215d35bcae90194e0ff90:/tasklib/task.py diff --git a/tasklib/task.py b/tasklib/task.py index b6c3d09..4f10b9d 100644 --- a/tasklib/task.py +++ b/tasklib/task.py @@ -4,32 +4,84 @@ import datetime import json import logging import os +import pytz import six -import subprocess +import sys +import tzlocal + +from backends import TaskWarrior, TaskWarriorException DATE_FORMAT = '%Y%m%dT%H%M%SZ' +DATE_FORMAT_CALC = '%Y-%m-%dT%H:%M:%S' REPR_OUTPUT_SIZE = 10 PENDING = 'pending' COMPLETED = 'completed' -VERSION_2_1_0 = six.u('2.1.0') -VERSION_2_2_0 = six.u('2.2.0') -VERSION_2_3_0 = six.u('2.3.0') -VERSION_2_4_0 = six.u('2.4.0') - logger = logging.getLogger(__name__) +local_zone = tzlocal.get_localzone() + + +class ReadOnlyDictView(object): + """ + Provides simplified read-only view upon dict object. + """ + + def __init__(self, viewed_dict): + self.viewed_dict = viewed_dict + + def __getitem__(self, key): + return copy.deepcopy(self.viewed_dict.__getitem__(key)) + def __contains__(self, k): + return self.viewed_dict.__contains__(k) -class TaskWarriorException(Exception): - pass + def __iter__(self): + for value in self.viewed_dict: + yield copy.deepcopy(value) + + def __len__(self): + return len(self.viewed_dict) + + def get(self, key, default=None): + return copy.deepcopy(self.viewed_dict.get(key, default)) + + def items(self): + return [copy.deepcopy(v) for v in self.viewed_dict.items()] + + def values(self): + return [copy.deepcopy(v) for v in self.viewed_dict.values()] class SerializingObject(object): """ Common ancestor for TaskResource & TaskFilter, since they both need to serialize arguments. + + Serializing method should hold the following contract: + - any empty value (meaning removal of the attribute) + is deserialized into a empty string + - None denotes a empty value for any attribute + + Deserializing method should hold the following contract: + - None denotes a empty value for any attribute (however, + this is here as a safeguard, TaskWarrior currently does + not export empty-valued attributes) if the attribute + is not iterable (e.g. list or set), in which case + a empty iterable should be used. + + Normalizing methods should hold the following contract: + - They are used to validate and normalize the user input. + Any attribute value that comes from the user (during Task + initialization, assignign values to Task attributes, or + filtering by user-provided values of attributes) is first + validated and normalized using the normalize_{key} method. + - If validation or normalization fails, normalizer is expected + to raise ValueError. """ + def __init__(self, warrior): + self.warrior = warrior + def _deserialize(self, key, value): hydrate_func = getattr(self, 'deserialize_{0}'.format(key), lambda x: x if x != '' else None) @@ -40,15 +92,40 @@ class SerializingObject(object): lambda x: x if x is not None else '') return dehydrate_func(value) + def _normalize(self, key, value): + """ + Use normalize_ methods to normalize user input. Any user + input will be normalized at the moment it is used as filter, + or entered as a value of Task attribute. + """ + + # None value should not be converted by normalizer + if value is None: + return None + + normalize_func = getattr(self, 'normalize_{0}'.format(key), + lambda x: x) + + return normalize_func(value) + def timestamp_serializer(self, date): if not date: - return None + return '' + + # Any serialized timestamp should be localized, we need to + # convert to UTC before converting to string (DATE_FORMAT uses UTC) + date = date.astimezone(pytz.utc) + return date.strftime(DATE_FORMAT) def timestamp_deserializer(self, date_str): if not date_str: return None - return datetime.datetime.strptime(date_str, DATE_FORMAT) + + # Return timestamp localized in the local zone + naive_timestamp = datetime.datetime.strptime(date_str, DATE_FORMAT) + localized_timestamp = pytz.utc.localize(naive_timestamp) + return localized_timestamp.astimezone(local_zone) def serialize_entry(self, value): return self.timestamp_serializer(value) @@ -56,36 +133,81 @@ class SerializingObject(object): def deserialize_entry(self, value): return self.timestamp_deserializer(value) + def normalize_entry(self, value): + return self.datetime_normalizer(value) + def serialize_modified(self, value): return self.timestamp_serializer(value) def deserialize_modified(self, value): return self.timestamp_deserializer(value) + def normalize_modified(self, value): + return self.datetime_normalizer(value) + + def serialize_start(self, value): + return self.timestamp_serializer(value) + + def deserialize_start(self, value): + return self.timestamp_deserializer(value) + + def normalize_start(self, value): + return self.datetime_normalizer(value) + + def serialize_end(self, value): + return self.timestamp_serializer(value) + + def deserialize_end(self, value): + return self.timestamp_deserializer(value) + + def normalize_end(self, value): + return self.datetime_normalizer(value) + def serialize_due(self, value): return self.timestamp_serializer(value) def deserialize_due(self, value): return self.timestamp_deserializer(value) + def normalize_due(self, value): + return self.datetime_normalizer(value) + def serialize_scheduled(self, value): return self.timestamp_serializer(value) def deserialize_scheduled(self, value): return self.timestamp_deserializer(value) + def normalize_scheduled(self, value): + return self.datetime_normalizer(value) + def serialize_until(self, value): return self.timestamp_serializer(value) def deserialize_until(self, value): return self.timestamp_deserializer(value) + def normalize_until(self, value): + return self.datetime_normalizer(value) + def serialize_wait(self, value): return self.timestamp_serializer(value) def deserialize_wait(self, value): return self.timestamp_deserializer(value) + def normalize_wait(self, value): + return self.datetime_normalizer(value) + + def serialize_annotations(self, value): + value = value if value is not None else [] + + # This may seem weird, but it's correct, we want to export + # a list of dicts as serialized value + serialized_annotations = [json.loads(annotation.export_data()) + for annotation in value] + return serialized_annotations if serialized_annotations else '' + def deserialize_annotations(self, data): return [TaskAnnotation(self, d) for d in data] if data else [] @@ -93,41 +215,101 @@ class SerializingObject(object): return ','.join(tags) if tags else '' def deserialize_tags(self, tags): - if isinstance(tags, basestring): + if isinstance(tags, six.string_types): return tags.split(',') if tags else [] - return tags + return tags or [] - def serialize_depends(self, cur_dependencies): + def serialize_depends(self, value): # Return the list of uuids - return ','.join(task['uuid'] for task in cur_dependencies) + value = value if value is not None else set() + return ','.join(task['uuid'] for task in value) def deserialize_depends(self, raw_uuids): - raw_uuids = raw_uuids or '' # Convert None to empty string - uuids = raw_uuids.split(',') + raw_uuids = raw_uuids or [] # Convert None to empty list + + # TW 2.4.4 encodes list of dependencies as a single string + if type(raw_uuids) is not list: + uuids = raw_uuids.split(',') + # TW 2.4.5 and later exports them as a list, no conversion needed + else: + uuids = raw_uuids + return set(self.warrior.tasks.get(uuid=uuid) for uuid in uuids if uuid) + def datetime_normalizer(self, value): + """ + Normalizes date/datetime value (considered to come from user input) + to localized datetime value. Following conversions happen: + + naive date -> localized datetime with the same date, and time=midnight + naive datetime -> localized datetime with the same value + localized datetime -> localized datetime (no conversion) + """ + + if (isinstance(value, datetime.date) + and not isinstance(value, datetime.datetime)): + # Convert to local midnight + value_full = datetime.datetime.combine(value, datetime.time.min) + localized = local_zone.localize(value_full) + elif isinstance(value, datetime.datetime): + if value.tzinfo is None: + # Convert to localized datetime object + localized = local_zone.localize(value) + else: + # If the value is already localized, there is no need to change + # time zone at this point. Also None is a valid value too. + localized = value + elif (isinstance(value, six.string_types) + and self.warrior.version >= VERSION_2_4_0): + # For strings, use 'task calc' to evaluate the string to datetime + # available since TW 2.4.0 + args = value.split() + result = self.warrior.execute_command(['calc'] + args) + naive = datetime.datetime.strptime(result[0], DATE_FORMAT_CALC) + localized = local_zone.localize(naive) + else: + raise ValueError("Provided value could not be converted to " + "datetime, its type is not supported: {}" + .format(type(value))) + + return localized + + def normalize_uuid(self, value): + # Enforce sane UUID + if not isinstance(value, six.string_types) or value == '': + raise ValueError("UUID must be a valid non-empty string, " + "not: {}".format(value)) + + return value + class TaskResource(SerializingObject): read_only_fields = [] def _load_data(self, data): - self._data = data + self._data = dict((key, self._deserialize(key, value)) + for key, value in data.items()) # We need to use a copy for original data, so that changes - # are not propagated. Shallow copy is alright, since data dict uses only - # primitive data types - self._original_data = data.copy() + # are not propagated. + self._original_data = copy.deepcopy(self._data) - def _update_data(self, data, update_original=False): + def _update_data(self, data, update_original=False, remove_missing=False): """ Low level update of the internal _data dict. Data which are coming as updates should already be serialized. If update_original is True, the original_data dict is updated as well. """ + self._data.update(dict((key, self._deserialize(key, value)) + for key, value in data.items())) - self._data.update(data) + # In certain situations, we want to treat missing keys as removals + if remove_missing: + for key in set(self._data.keys()) - set(data.keys()): + self._data[key] = None if update_original: - self._original_data.update(data) + self._original_data = copy.deepcopy(self._data) + def __getitem__(self, key): # This is a workaround to make TaskResource non-iterable @@ -138,12 +320,18 @@ class TaskResource(SerializingObject): except ValueError: pass - return self._deserialize(key, self._data.get(key)) + if key not in self._data: + self._data[key] = self._deserialize(key, None) + + return self._data.get(key) def __setitem__(self, key, value): if key in self.read_only_fields: raise RuntimeError('Field \'%s\' is read-only' % key) - self._data[key] = self._serialize(key, value) + + # Normalize the user input before saving it + value = self._normalize(key, value) + self._data[key] = value def __str__(self): s = six.text_type(self.__unicode__()) @@ -154,13 +342,48 @@ class TaskResource(SerializingObject): def __repr__(self): return str(self) + def export_data(self): + """ + Exports current data contained in the Task as JSON + """ + + # We need to remove spaces for TW-1504, use custom separators + data_tuples = ((key, self._serialize(key, value)) + for key, value in six.iteritems(self._data)) + + # Empty string denotes empty serialized value, we do not want + # to pass that to TaskWarrior. + data_tuples = filter(lambda t: t[1] is not '', data_tuples) + data = dict(data_tuples) + return json.dumps(data, separators=(',',':')) + + @property + def _modified_fields(self): + writable_fields = set(self._data.keys()) - set(self.read_only_fields) + for key in writable_fields: + new_value = self._data.get(key) + old_value = self._original_data.get(key) + + # Make sure not to mark data removal as modified field if the + # field originally had some empty value + if key in self._data and not new_value and not old_value: + continue + + if new_value != old_value: + yield key + + @property + def modified(self): + return bool(list(self._modified_fields)) + class TaskAnnotation(TaskResource): read_only_fields = ['entry', 'description'] - def __init__(self, task, data={}): + def __init__(self, task, data=None): self.task = task - self._load_data(data) + self._load_data(data or dict()) + super(TaskAnnotation, self).__init__(task.warrior) def remove(self): self.task.remove_annotation(self) @@ -168,6 +391,11 @@ class TaskAnnotation(TaskResource): def __unicode__(self): return self['description'] + def __eq__(self, other): + # consider 2 annotations equal if they belong to the same task, and + # their data dics are the same + return self.task == other.task and self._data == other._data + __repr__ = __unicode__ @@ -189,6 +417,18 @@ class Task(TaskResource): """ pass + class ActiveTask(Exception): + """ + Raised when the operation cannot be performed on the active task. + """ + pass + + class InactiveTask(Exception): + """ + Raised when the operation cannot be performed on an inactive task. + """ + pass + class NotSaved(Exception): """ Raised when the operation cannot be performed on the task, because @@ -196,8 +436,48 @@ class Task(TaskResource): """ pass + @classmethod + def from_input(cls, input_file=sys.stdin, modify=None, warrior=None): + """ + Creates a Task object, directly from the stdin, by reading one line. + If modify=True, two lines are used, first line interpreted as the + original state of the Task object, and second line as its new, + modified value. This is consistent with the TaskWarrior's hook + system. + + Object created by this method should not be saved, deleted + or refreshed, as t could create a infinite loop. For this + reason, TaskWarrior instance is set to None. + + Input_file argument can be used to specify the input file, + but defaults to sys.stdin. + """ + + # Detect the hook type if not given directly + name = os.path.basename(sys.argv[0]) + modify = name.startswith('on-modify') if modify is None else modify + + # Create the TaskWarrior instance if none passed + if warrior is None: + hook_parent_dir = os.path.dirname(os.path.dirname(sys.argv[0])) + warrior = TaskWarrior(data_location=hook_parent_dir) + + # TaskWarrior instance is set to None + task = cls(warrior) + + # Load the data from the input + task._load_data(json.loads(input_file.readline().strip())) + + # If this is a on-modify event, we are provided with additional + # line of input, which provides updated data + if modify: + task._update_data(json.loads(input_file.readline().strip()), + remove_missing=True) + + return task + def __init__(self, warrior, **kwargs): - self.warrior = warrior + super(Task, self).__init__(warrior) # Check that user is not able to set read-only value in __init__ for key in kwargs.keys(): @@ -209,8 +489,12 @@ class Task(TaskResource): # __init__ methods, that would be confusing # Rather unfortunate syntax due to python2.6 comaptiblity - self._load_data(dict((key, self._serialize(key, value)) - for (key, value) in six.iteritems(kwargs))) + self._data = dict((key, self._normalize(key, value)) + for (key, value) in six.iteritems(kwargs)) + self._original_data = copy.deepcopy(self._data) + + # Provide read only access to the original data + self.original = ReadOnlyDictView(self._original_data) def __unicode__(self): return self['description'] @@ -232,13 +516,6 @@ class Task(TaskResource): # If the tasks are not saved, return hash of instance id return id(self).__hash__() - @property - def _modified_fields(self): - writable_fields = set(self._data.keys()) - set(self.read_only_fields) - for key in writable_fields: - if self._data.get(key) != self._original_data.get(key): - yield key - @property def completed(self): return self['status'] == six.text_type('completed') @@ -255,13 +532,17 @@ class Task(TaskResource): def pending(self): return self['status'] == six.text_type('pending') + @property + def active(self): + return self['start'] is not None + @property def saved(self): return self['uuid'] is not None or self['id'] is not None def serialize_depends(self, cur_dependencies): # Check that all the tasks are saved - for task in cur_dependencies: + for task in (cur_dependencies or set()): if not task.saved: raise Task.NotSaved('Task \'%s\' needs to be saved before ' 'it can be set as dependency.' % task) @@ -276,8 +557,7 @@ class Task(TaskResource): # to keep a list of all depedencies in the _data dictionary, # not just currently added/removed ones - old_dependencies_raw = self._original_data.get('depends','') - old_dependencies = self.deserialize_depends(old_dependencies_raw) + old_dependencies = self._original_data.get('depends', set()) added = self['depends'] - old_dependencies removed = old_dependencies - self['depends'] @@ -294,7 +574,7 @@ class Task(TaskResource): if self.warrior.version < VERSION_2_4_0: return self._data['description'] else: - return "description:'{0}'".format(self._data['description'] or '') + return six.u("description:'{0}'").format(self._data['description'] or '') def delete(self): if not self.saved: @@ -309,8 +589,41 @@ class Task(TaskResource): self.warrior.execute_command([self['uuid'], 'delete']) # Refresh the status again, so that we have updated info stored + self.refresh(only_fields=['status', 'start', 'end']) + + def start(self): + if not self.saved: + raise Task.NotSaved("Task needs to be saved before it can be started") + + # Refresh, and raise exception if task is already completed/deleted + self.refresh(only_fields=['status']) + + if self.completed: + raise Task.CompletedTask("Cannot start a completed task") + elif self.deleted: + raise Task.DeletedTask("Deleted task cannot be started") + elif self.active: + raise Task.ActiveTask("Task is already active") + + self.warrior.execute_command([self['uuid'], 'start']) + + # Refresh the status again, so that we have updated info stored + self.refresh(only_fields=['status', 'start']) + + def stop(self): + if not self.saved: + raise Task.NotSaved("Task needs to be saved before it can be stopped") + + # Refresh, and raise exception if task is already completed/deleted self.refresh(only_fields=['status']) + if not self.active: + raise Task.InactiveTask("Cannot stop an inactive task") + + self.warrior.execute_command([self['uuid'], 'stop']) + + # Refresh the status again, so that we have updated info stored + self.refresh(only_fields=['status', 'start']) def done(self): if not self.saved: @@ -324,12 +637,19 @@ class Task(TaskResource): elif self.deleted: raise Task.DeletedTask("Deleted task cannot be completed") + # Older versions of TW do not stop active task at completion + if self.warrior.version < VERSION_2_4_0 and self.active: + self.stop() + self.warrior.execute_command([self['uuid'], 'done']) # Refresh the status again, so that we have updated info stored - self.refresh(only_fields=['status']) + self.refresh(only_fields=['status', 'start', 'end']) def save(self): + if self.saved and not self.modified: + return + args = [self['uuid'], 'modify'] if self.saved else ['add'] args.extend(self._get_modified_fields_as_args()) output = self.warrior.execute_command(args) @@ -345,9 +665,18 @@ class Task(TaskResource): "task: %s" % '\n'.join(id_lines)) # Circumvent the ID storage, since ID is considered read-only - self._data['id'] = int(id_lines[0].split(' ')[2].rstrip('.')) + identifier = id_lines[0].split(' ')[2].rstrip('.') - self.refresh() + # Identifier can be either ID or UUID for completed tasks + try: + self._data['id'] = int(identifier) + except ValueError: + self._data['uuid'] = identifier + + # Refreshing is very important here, as not only modification time + # is updated, but arbitrary attribute may have changed due hooks + # altering the data before saving + self.refresh(after_save=True) def add_annotation(self, annotation): if not self.saved: @@ -372,13 +701,22 @@ class Task(TaskResource): def add_field(field): # Add the output of format_field method to args list (defaults to - # field:'value') - format_default = lambda k: "{0}:{1}".format(k, - "'{0}'".format(self._data[k]) - if self._data[k] is not None - else '') + # field:value) + serialized_value = self._serialize(field, self._data[field]) + + # Empty values should not be enclosed in quotation marks, see + # TW-1510 + if serialized_value is '': + escaped_serialized_value = '' + else: + escaped_serialized_value = six.u("'{0}'").format(serialized_value) + + format_default = lambda: six.u("{0}:{1}").format(field, + escaped_serialized_value) + format_func = getattr(self, 'format_{0}'.format(field), - lambda: format_default(field)) + format_default) + args.append(format_func()) # If we're modifying saved task, simply pass on all modified fields @@ -394,7 +732,7 @@ class Task(TaskResource): return args - def refresh(self, only_fields=[]): + def refresh(self, only_fields=None, after_save=False): # Raise error when trying to refresh a task that has not been saved if not self.saved: raise Task.NotSaved("Task needs to be saved to be refreshed") @@ -403,7 +741,39 @@ class Task(TaskResource): # of newly saved tasks. Any other place in the code is fine # with using UUID only. args = [self['uuid'] or self['id'], 'export'] - new_data = json.loads(self.warrior.execute_command(args)[0]) + output = self.warrior.execute_command(args) + + def valid(output): + return len(output) == 1 and output[0].startswith('{') + + # For older TW versions attempt to uniquely locate the task + # using the data we have if it has been just saved. + # This can happen when adding a completed task on older TW versions. + if (not valid(output) and self.warrior.version < VERSION_2_4_5 + and after_save): + + # Make a copy, removing ID and UUID. It's most likely invalid + # (ID 0) if it failed to match a unique task. + data = copy.deepcopy(self._data) + data.pop('id', None) + data.pop('uuid', None) + + taskfilter = TaskFilter(self.warrior) + for key, value in data.items(): + taskfilter.add_filter_param(key, value) + + output = self.warrior.execute_command(['export', '--'] + + taskfilter.get_filter_params()) + + # If more than 1 task has been matched still, raise an exception + if not valid(output): + raise TaskWarriorException( + "Unique identifiers {0} with description: {1} matches " + "multiple tasks: {2}".format( + self['uuid'] or self['id'], self['description'], output) + ) + + new_data = json.loads(output[0]) if only_fields: to_update = dict( [(k, new_data.get(k)) for k in only_fields]) @@ -411,14 +781,14 @@ class Task(TaskResource): else: self._load_data(new_data) - class TaskFilter(SerializingObject): """ A set of parameters to filter the task list with. """ - def __init__(self, filter_params=[]): - self.filter_params = filter_params + def __init__(self, warrior, filter_params=None): + self.filter_params = filter_params or [] + super(TaskFilter, self).__init__(warrior) def add_filter(self, filter_str): self.filter_params.append(filter_str) @@ -429,6 +799,9 @@ class TaskFilter(SerializingObject): # Replace the value with empty string, since that is the # convention in TW for empty values attribute_key = key.split('.')[0] + + # Since this is user input, we need to normalize before we serialize + value = self._normalize(attribute_key, value) value = self._serialize(attribute_key, value) # If we are filtering by uuid:, do not use uuid keyword @@ -441,16 +814,18 @@ class TaskFilter(SerializingObject): # We enforce equality match by using 'is' (or 'none') modifier # Without using this syntax, filter fails due to TW-1479 - modifier = '.is' if value else '.none' - key = key + modifier if '.' not in key else key + # which is, however, fixed in 2.4.5 + if self.warrior.version < VERSION_2_4_5: + modifier = '.is' if value else '.none' + key = key + modifier if '.' not in key else key - self.filter_params.append("{0}:{1}".format(key, value)) + self.filter_params.append(six.u("{0}:{1}").format(key, value)) def get_filter_params(self): return [f for f in self.filter_params if f] def clone(self): - c = self.__class__() + c = self.__class__(self.warrior) c.filter_params = list(self.filter_params) return c @@ -463,7 +838,7 @@ class TaskQuerySet(object): def __init__(self, warrior=None, filter_obj=None): self.warrior = warrior self._result_cache = None - self.filter_obj = filter_obj or TaskFilter() + self.filter_obj = filter_obj or TaskFilter(warrior) def __deepcopy__(self, memo): """ @@ -563,72 +938,3 @@ class TaskQuerySet(object): raise ValueError( 'get() returned more than one Task -- it returned {0}! ' 'Lookup parameters were {1}'.format(num, kwargs)) - - -class TaskWarrior(object): - def __init__(self, data_location='~/.task', create=True): - data_location = os.path.expanduser(data_location) - if create and not os.path.exists(data_location): - os.makedirs(data_location) - self.config = { - 'data.location': os.path.expanduser(data_location), - 'confirmation': 'no', - 'dependency.confirmation': 'no', # See TW-1483 or taskrc man page - } - self.tasks = TaskQuerySet(self) - self.version = self._get_version() - - def _get_command_args(self, args, config_override={}): - command_args = ['task', 'rc:/'] - config = self.config.copy() - config.update(config_override) - for item in config.items(): - command_args.append('rc.{0}={1}'.format(*item)) - command_args.extend(map(str, args)) - return command_args - - def _get_version(self): - p = subprocess.Popen( - ['task', '--version'], - stdout=subprocess.PIPE, - stderr=subprocess.PIPE) - stdout, stderr = [x.decode('utf-8') for x in p.communicate()] - return stdout.strip('\n') - - def execute_command(self, args, config_override={}): - command_args = self._get_command_args( - args, config_override=config_override) - logger.debug(' '.join(command_args)) - p = subprocess.Popen(command_args, stdout=subprocess.PIPE, - stderr=subprocess.PIPE) - stdout, stderr = [x.decode('utf-8') for x in p.communicate()] - if p.returncode: - if stderr.strip(): - error_msg = stderr.strip().splitlines()[-1] - else: - error_msg = stdout.strip() - raise TaskWarriorException(error_msg) - return stdout.strip().split('\n') - - def filter_tasks(self, filter_obj): - args = ['export', '--'] + filter_obj.get_filter_params() - tasks = [] - for line in self.execute_command(args): - if line: - data = line.strip(',') - try: - filtered_task = Task(self) - filtered_task._load_data(json.loads(data)) - tasks.append(filtered_task) - except ValueError: - raise TaskWarriorException('Invalid JSON: %s' % data) - return tasks - - def merge_with(self, path, push=False): - path = path.rstrip('/') + '/' - self.execute_command(['merge', path], config_override={ - 'merge.autopush': 'yes' if push else 'no', - }) - - def undo(self): - self.execute_command(['undo'])