pylint.checkers.refactoring.ImplicitBooleanessChecker

class documentation

class ImplicitBooleanessChecker(checkers.BaseChecker): (source)

Checks for incorrect usage of comparisons or len() inside conditions. Incorrect usage of len() Pep8 states: For sequences, (strings, lists, tuples), use the fact that empty sequences are false. Yes: if not seq: if seq: No: if len(seq): if not len(seq): Problems detected: * if len(sequence): * if not len(sequence): * elif len(sequence): * elif not len(sequence): * while len(sequence): * while not len(sequence): * assert len(sequence): * assert not len(sequence): * bool(len(sequence)) Incorrect usage of empty literal sequences; (), [], {}, For empty sequences, (dicts, lists, tuples), use the fact that empty sequences are false. Yes: if variable: if not variable No: if variable == empty_literal: if variable != empty_literal: Problems detected: * comparison such as variable == empty_literal: * comparison such as variable != empty_literal:

Static Method	`base_names_of_instance`	Return all names inherited by a class instance or those returned by a function.
Static Method	`instance_has_bool`	Undocumented
Method	`visit_call`	Undocumented
Method	`visit_compare`	Undocumented
Method	`visit_unaryop`	`not len(S)` must become `not S` regardless if the parent block is a test condition or something else (boolean expression) e.g. `if not len(S):`.
Class Variable	`msgs`	Undocumented
Class Variable	`name`	Name of the provider.
Class Variable	`options`	Options provided by this provider.
Method	`_check_use_implicit_booleaness_not_comparison`	Check for left side and right side of the node for empty literals.
Method	`_get_node_description`	Undocumented
Method	`_implicit_booleaness_message_args`	Helper to get the right message for "use-implicit-booleaness-not-comparison".

Inherited from BaseChecker:

Method	`__eq__`	Permit to assert Checkers are equal.
Method	`__gt__`	Sorting of checkers.
Method	`__hash__`	Make Checker hashable.
Method	`__init__`	Checker instances should have the linter as argument.
Method	`__repr__`	Undocumented
Method	`__str__`	This might be incomplete because multiple classes inheriting BaseChecker can have the same name.
Method	`add_message`	Undocumented
Method	`check_consistency`	Check the consistency of msgid.
Method	`close`	Called after visiting project (i.e set of modules).
Method	`create_message_definition_from_tuple`	Undocumented
Method	`get_full_documentation`	Undocumented
Method	`get_map_data`	Undocumented
Method	`get_message_definition`	Undocumented
Method	`open`	Called before visiting project (i.e. set of modules).
Method	`reduce_map_data`	Undocumented
Class Variable	`enabled`	Undocumented
Class Variable	`reports`	Undocumented
Instance Variable	`linter`	Undocumented
Property	`messages`	Undocumented

Inherited from _ArgumentsProvider (via BaseChecker):

Method	`get_option_def`	DEPRECATED: Return the dictionary defining an option given its name.
Method	`level.setter`	Undocumented
Method	`load_defaults`	DEPRECATED: Initialize the provider using default values.
Method	`option_attrname`	DEPRECATED: Get the config attribute corresponding to opt.
Method	`option_value`	DEPRECATED: Get the current value for the given option.
Method	`options_and_values`	DEPRECATED.
Method	`options_by_section`	DEPRECATED: Return an iterator on options grouped by section.
Method	`set_option`	DEPRECATED: Method called to set an option (registered in the options list).
Class Variable	`option_groups_descs`	Option groups of this provider and their descriptions.
Property	`config`	Undocumented
Property	`level`	Undocumented
Instance Variable	`_arguments_manager`	The manager that will parse and register any options provided.
Instance Variable	`_level`	Undocumented

@staticmethod
def base_names_of_instance(node: util.UninferableBase|bases.Instance) -> list[str]: (source) ¶

Return all names inherited by a class instance or those returned by a function. The inherited names include 'object'.

@staticmethod
def instance_has_bool(class_def: nodes.ClassDef) -> bool: (source) ¶

Undocumented

@utils.only_required_for_messages('use-implicit-booleaness-not-len')
def visit_call(self, node: nodes.Call): (source) ¶

Undocumented

@utils.only_required_for_messages('use-implicit-booleaness-not-comparison')
def visit_compare(self, node: nodes.Compare): (source) ¶

Undocumented

@utils.only_required_for_messages('use-implicit-booleaness-not-len')
def visit_unaryop(self, node: nodes.UnaryOp): (source) ¶

`not len(S)` must become `not S` regardless if the parent block is a test condition or something else (boolean expression) e.g. `if not len(S):`.

msgs: dict = (source) ¶

overrides pylint.checkers.BaseChecker.msgs

Undocumented

name: str = (source) ¶

overrides pylint.checkers.BaseChecker.name

Name of the provider.

options: tuple = (source) ¶

overrides pylint.checkers.BaseChecker.options

Options provided by this provider.

def _check_use_implicit_booleaness_not_comparison(self, node: nodes.Compare): (source) ¶

Check for left side and right side of the node for empty literals.

def _get_node_description(self, node: nodes.NodeNG) -> str: (source) ¶

Undocumented

def _implicit_booleaness_message_args(self, literal_node: nodes.NodeNG, operator: str, target_node: nodes.NodeNG) -> tuple[str, str, str]: (source) ¶

Helper to get the right message for "use-implicit-booleaness-not-comparison".