def visit_classdef(self, node: nodes.ClassDef) -> None:
"""Visit an astroid.Class node.
* set the locals_type and instance_attrs_type mappings
* set the implements list and build it
* optionally tag the node with a unique id
"""
if hasattr(node, "locals_type"):
return
node.locals_type = collections.defaultdict(list)
if self.tag:
node.uid = self.generate_id()
# resolve ancestors
for baseobj in node.ancestors(recurs=False):
specializations = getattr(baseobj, "specializations", [])
specializations.append(node)
baseobj.specializations = specializations
# resolve instance attributes
node.instance_attrs_type = collections.defaultdict(list)
for assignattrs in node.instance_attrs.values():
for assignattr in assignattrs:
if not isinstance(assignattr, nodes.Unknown):
self.handle_assignattr_type(assignattr, node)
# resolve implemented interface
try:
node.implements = list(interfaces(node, self.inherited_interfaces))
except astroid.InferenceError:
node.implements = []
def _get_parents_iter(
node: nodes.ClassDef,
ignored_parents: FrozenSet[str]) -> Iterator[nodes.ClassDef]:
r"""Get parents of ``node``, excluding ancestors of ``ignored_parents``.
If we have the following inheritance diagram:
F
/
D E
\/
B C
\/
A # class A(B, C): ...
And ``ignored_parents`` is ``{"E"}``, then this function will return
``{A, B, C, D}`` -- both ``E`` and its ancestors are excluded.
"""
parents: Set[nodes.ClassDef] = set()
to_explore = cast(List[nodes.ClassDef], list(node.ancestors(recurs=False)))
while to_explore:
parent = to_explore.pop()
if parent.qname() in ignored_parents:
continue
if parent not in parents:
# This guard might appear to be performing the same function as
# adding the resolved parents to a set to eliminate duplicates
# (legitimate due to diamond inheritance patterns), but its
# additional purpose is to prevent cycles (not normally possible,
# but potential due to inference) and thus guarantee termination
# of the while-loop
yield parent
parents.add(parent)
to_explore.extend(parent.ancestors(recurs=False))
def visit_classdef(self, node: nodes.ClassDef) -> None:
"""Called when a ClassDef node is visited."""
ancestor: nodes.ClassDef
for ancestor in node.ancestors():
for class_matches in self._class_matchers:
if ancestor.name == class_matches.base_class:
self._visit_class_functions(node, class_matches.matches)
def visit_classdef(self, node: nodes.ClassDef):
"""check size of inheritance hierarchy and number of instance attributes"""
nb_parents = sum(
1 for ancestor in node.ancestors()
if ancestor.qname() not in STDLIB_CLASSES_IGNORE_ANCESTOR)
if nb_parents > self.config.max_parents:
self.add_message(
"too-many-ancestors",
node=node,
args=(nb_parents, self.config.max_parents),
)
if len(node.instance_attrs) > self.config.max_attributes:
self.add_message(
"too-many-instance-attributes",
node=node,
args=(len(node.instance_attrs), self.config.max_attributes),
)
def leave_classdef(self, node: nodes.ClassDef) -> None:
"""check number of public methods"""
my_methods = sum(1 for method in node.mymethods()
if not method.name.startswith("_"))
# Does the class contain less than n public methods ?
# This checks only the methods defined in the current class,
# since the user might not have control over the classes
# from the ancestors. It avoids some false positives
# for classes such as unittest.TestCase, which provides
# a lot of assert methods. It doesn't make sense to warn
# when the user subclasses TestCase to add his own tests.
if my_methods > self.config.max_public_methods:
self.add_message(
"too-many-public-methods",
node=node,
args=(my_methods, self.config.max_public_methods),
)
# Stop here if the class is excluded via configuration.
if node.type == "class" and self._exclude_too_few_public_methods:
for ancestor in node.ancestors():
if any(
pattern.match(ancestor.qname())
for pattern in self._exclude_too_few_public_methods):
return
# Stop here for exception, metaclass, interface classes and other
# classes for which we don't need to count the methods.
if node.type != "class" or _is_exempt_from_public_methods(node):
return
# Does the class contain more than n public methods ?
# This checks all the methods defined by ancestors and
# by the current class.
all_methods = _count_methods_in_class(node)
if all_methods < self.config.min_public_methods:
self.add_message(
"too-few-public-methods",
node=node,
args=(all_methods, self.config.min_public_methods),
)
def visit_classdef(self, node: nodes.ClassDef) -> None:
"""Visit an astroid.Class node.
* set the locals_type and instance_attrs_type mappings
* set the implements list and build it
* optionally tag the node with a unique id
"""
if hasattr(node, "locals_type"):
return
node.locals_type = collections.defaultdict(list)
if self.tag:
node.uid = self.generate_id()
# resolve ancestors
for baseobj in node.ancestors(recurs=False):
specializations = getattr(baseobj, "specializations", [])
specializations.append(node)
baseobj.specializations = specializations
# resolve instance attributes
node.instance_attrs_type = collections.defaultdict(list)
for assignattrs in tuple(node.instance_attrs.values()):
for assignattr in assignattrs:
if not isinstance(assignattr, nodes.Unknown):
self.handle_assignattr_type(assignattr, node)
# resolve implemented interface
try:
ifaces = interfaces(node)
if ifaces is not None:
node.implements = list(ifaces)
if node.implements:
# TODO: 3.0: Remove support for __implements__
warnings.warn(
"pyreverse will drop support for resolving and displaying implemented interfaces in pylint 3.0. "
"The implementation relies on the '__implements__' attribute proposed in PEP 245, which was rejected "
"in 2006.",
DeprecationWarning,
)
else:
node.implements = []
except astroid.InferenceError:
node.implements = []
def visit_classdef(self, ast: ast_node.ClassDef):
self.write("class %s {" % ast.name)
self.indent += 1
for instance_attrs in ast.instance_attrs.values():
for attr in instance_attrs:
if isinstance(attr, ast_node.AssignAttr):
attr.accept(self)
break
for local in ast.values():
local.accept(self)
self.indent -= 1
self.write("}")
for anc in ast.ancestors(recurs=False):
cls = next(anc.infer())
if isinstance(cls, ast_node.ClassDef):
module = cls.root().name
if is_target_module(module):
self.write("%s <|- %s.%s" % (ast.name, cls.root().name, cls.name))
def _process_class_member_and_attrs(cldef: ClassDef,
pkgfiles: Set[str]) -> Set[str]:
"""
Determine the class attributes, methods and instance attributes defined by
a class. The function will inspect and populate them from the parents while
the parent is defined by a module file in the same mmpack package.
This function is called recursively to populate a class.
Args:
cldef: the astroid node defining the class
pkgfiles: set of files in the same mmpack package
Returns:
set of name corresponding to the class attributes and methods and
instance attributes.
"""
syms = set()
# add member and attributes from parent classes implemented in files of
# the same package
for base in cldef.ancestors(recurs=False):
mod = base.root()
if _is_module_packaged(mod, pkgfiles):
syms.update(_process_class_member_and_attrs(base, pkgfiles))
# Add public class attributes
for attr in cldef.locals:
if (isinstance(cldef.locals[attr][-1], AssignName)
and _is_public_sym(attr)):
syms.add(attr)
# Add public class methods and instance attributes
syms.update({m.name for m in cldef.mymethods() if _is_public_sym(m.name)})
syms.update({a for a in cldef.instance_attrs if _is_public_sym(a)})
return syms
def base_classes_of_node(instance: nodes.ClassDef) -> List[nodes.Name]:
"""Return all the classes names that a ClassDef inherit from including 'object'."""
try:
return [instance.name] + [x.name for x in instance.ancestors()]
except TypeError:
return [instance.name]
