def move(self, path, new_parent_path):
"""
Move category from anywhere to anywhere in the tree.
Category can only be moved 'under' a new parent. So it can't be moved on top of the root category.
Makes sure that:
Root category cannot be moved.
Parameters:
path(str,iterable,Path): path of the category to be moved.
new_parent_path(str,iterable,Path): path of the new parent of the category to be moved.
Returns:
None
Raises:
RootMoveError
"""
path = Path(path)
new_parent_path = Path(new_parent_path)
category = self.get(path)
if category.is_root():
raise RootMoveError()
new_parent = self.get(new_parent_path)
category.parent._remove_child(category)
new_parent._add_child(category)
def path(self):
"""
Return the path from the root to the current category including the current one.
"""
if not self.parent:
return Path([self.name])
return Path(self.parent.path) + Path([self.name])
def test_find(tree):
found = tree._find(Path('food/fruits'))
assert isinstance(found, Category)
assert found.name == 'fruits'
found = tree._find(Path('food/fruits/apple'))
assert isinstance(found, Category)
assert found.name == 'apple'
found = tree._find(Path('food/fruits/apple/red'))
assert isinstance(found, Category)
assert found.name == 'red'
found = tree._find(Path('fruits/apple'))
assert found is None
found = tree._find(Path('apple'))
assert found is None
found = tree._find(Path('apple/red'))
assert found is None
found = tree._find(Path('red'))
assert found is None
found = tree._find(Path('carrot'))
assert found is None
def get(self, path):
"""
Get the category whose path is given as argument.
Search can be performed anywhere in the tree (cf sample diagram):
Valid searches:
tree.get('food') -> food (itself)
tree.get('fruits') -> fruits
tree.get('apple') -> apple
tree.get('fruits/apple') -> apple
tree.get('food/fruits/apple') -> apple
Invalid searches (return None):
tree.get('food/apple')
Parameters:
path(str,iterable,Path): path of the category that is searched for
Returns:
found(Category,None): the found category or None
"""
found = None
path = Path(path)
start = self._find_start(path)
if start:
found = start._find(path)
return found
def add(self, category, path=None):
"""
Add category under the given path.
Parameters:
category(Category): category to add under path
path(str,iterable,Path): path under which the category is to be added
Returns:
None
"""
if not path:
self._add_child(category)
else:
path = Path(path)
parent = self.get(path)
if not parent:
raise CategoryDoesNotExistError(path)
parent._add_child(category)
def delete(self, path):
"""
Remove the instance from parent's children.
A category can be deleted anywhere in the tree.
Makes sure that:
Root category cannot be deleted.
Parameters:
path(str,iterable,Path): path of the category to be deleted.
Returns:
None
Raises:
RootDeleteError
"""
to_delete = self.get(Path(path))
if to_delete.is_root():
raise RootDeleteError()
to_delete.parent._remove_child(to_delete)
def size(self, path=None):
"""
Return the number of all the categories under a given path including the root of the given tree.
Parameters:
path(str,iterable,Path): path of the category whose size should be returned
Return:
size(int): number of all categories under the current one
Raises:
CategoryDoesNotExistsError
"""
size = 1
if not path:
category = self
else:
category = self.get(Path(path))
if not category:
raise CategoryDoesNotExistError(path)
for child in category.children:
size = size + child.size()
return size