def walk(self, astroid: nodes.NodeNG) -> None:
"""Call visit events of astroid checkers for the given node, recurse on
its children, then leave events.
"""
cid = astroid.__class__.__name__.lower()
# Detect if the node is a new name for a deprecated alias.
# In this case, favour the methods for the deprecated
# alias if any, in order to maintain backwards
# compatibility.
visit_events: Sequence[AstCallback] = self.visit_events.get(cid, ())
leave_events: Sequence[AstCallback] = self.leave_events.get(cid, ())
try:
if astroid.is_statement:
self.nbstatements += 1
# generate events for this node on each checker
for callback in visit_events:
callback(astroid)
# recurse on children
for child in astroid.get_children():
self.walk(child)
for callback in leave_events:
callback(astroid)
except Exception:
if self.exception_msg is False:
file = getattr(astroid.root(), "file", None)
print(
f"Exception on node {repr(astroid)} in file '{file}'",
file=sys.stderr,
)
traceback.print_exc()
self.exception_msg = True
raise
def check_deprecated_method(self, node: nodes.Call,
inferred: nodes.NodeNG) -> None:
"""Executes the checker for the given node.
This method should be called from the checker implementing this mixin.
"""
# Reject nodes which aren't of interest to us.
if not isinstance(inferred, ACCEPTABLE_NODES):
return
if isinstance(node.func, nodes.Attribute):
func_name = node.func.attrname
elif isinstance(node.func, nodes.Name):
func_name = node.func.name
else:
# Not interested in other nodes.
return
if hasattr(inferred.parent, "qname") and inferred.parent.qname():
# Handling the situation when deprecated function is
# alias to existing function.
qnames = {
inferred.qname(),
f"{inferred.parent.qname()}.{func_name}",
func_name,
}
else:
qnames = {inferred.qname(), func_name}
if any(name in self.deprecated_methods() for name in qnames):
self.add_message("deprecated-method",
node=node,
args=(func_name, ))
return
num_of_args = len(node.args)
kwargs = {kw.arg for kw in node.keywords} if node.keywords else {}
deprecated_arguments = (self.deprecated_arguments(qn) for qn in qnames)
for position, arg_name in chain(*deprecated_arguments):
if arg_name in kwargs:
# function was called with deprecated argument as keyword argument
self.add_message("deprecated-argument",
node=node,
args=(arg_name, func_name))
elif position is not None and position < num_of_args:
# function was called with deprecated argument as positional argument
self.add_message("deprecated-argument",
node=node,
args=(arg_name, func_name))
def _modified_iterating_check_on_node_and_children(
self, body_node: nodes.NodeNG, iter_obj: nodes.NodeNG
) -> None:
"""See if node or any of its children raises modified iterating messages."""
self._modified_iterating_check(body_node, iter_obj)
for child in body_node.get_children():
self._modified_iterating_check_on_node_and_children(child, iter_obj)
def get_nodes(
self,
statement: nodes.NodeNG) -> Generator[nodes.NodeNG, None, None]:
multiple_nodes = lambda nodes_: chain.from_iterable(
self.get_nodes(node) for node in nodes_)
if isinstance(statement, nodes.Assign):
# RHS is evaluated before assigned in an assignment statement
yield from self.get_nodes(statement.value)
yield from multiple_nodes(
statement.targets) # statement.targets is a list of nodes
elif isinstance(statement, (nodes.ListComp, nodes.SetComp,
nodes.DictComp, nodes.GeneratorExp)):
# Comprehension targets are assigned before expression is evaluated.
yield from multiple_nodes(
statement.generators
) # statement.generators is a list of nodes
if not hasattr(statement, "elt"):
yield from self.get_nodes(
statement.key) # keys evaluated first
yield from self.get_nodes(statement.value)
else:
yield from self.get_nodes(statement.elt)
else:
yield from statement.nodes_of_class(
(nodes.AssignName, nodes.DelName, nodes.Name),
nodes.FunctionDef)
def ignore_type_check_filter(node: nc.NodeNG) -> nc.NodeNG:
"""Ignore stuff under 'if TYPE_CHECKING:' block at module level."""
# Look for a non-nested 'if TYPE_CHECKING:'
if (isinstance(node.test, astroid.Name)
and node.test.name == 'TYPE_CHECKING'
and isinstance(node.parent, astroid.Module)):
# Find the module node.
mnode = node
while mnode.parent is not None:
mnode = mnode.parent
# First off, remove any names that are getting defined
# in this block from the module locals.
for cnode in node.body:
_strip_import(cnode, mnode)
# Now replace the body with a simple 'pass'. This will
# keep pylint from complaining about grouped imports/etc.
passnode = astroid.Pass(parent=node,
lineno=node.lineno + 1,
col_offset=node.col_offset + 1)
node.body = [passnode]
return node
def ignore_type_check_filter(if_node: nc.NodeNG) -> nc.NodeNG:
"""Ignore stuff under 'if TYPE_CHECKING:' block at module level."""
# Look for a non-nested 'if TYPE_CHECKING:'
if (isinstance(if_node.test, astroid.Name)
and if_node.test.name == 'TYPE_CHECKING'
and isinstance(if_node.parent, astroid.Module)):
module_node = if_node.parent
# Remove any locals getting defined under this if statement.
# (ideally should recurse in case we have nested if statements/etc
# but keeping it simple for now).
for name, locations in list(module_node.locals.items()):
# Calc which remaining name locations are outside of the if
# block. Update or delete the list as needed.
new_locs = [l for l in locations if not _under_if(l, if_node)]
if len(new_locs) == len(locations):
continue
if new_locs:
module_node.locals[name] = new_locs
continue
del module_node.locals[name]
# Now replace its children with a simple pass statement.
passnode = astroid.Pass(parent=if_node,
lineno=if_node.lineno + 1,
col_offset=if_node.col_offset + 1)
if_node.body = [passnode]
return if_node
def is_requests_func(node: NodeNG) -> bool:
"""
Checks if the node represents a requests HTTP call function.
Examples are: requests.get/post/..., requests.Session.get/post/...
"""
# simple case
if isinstance(node, nodes.Attribute) and node.attrname in SESSION_METHODS:
if (
is_requests_api_module(node.expr)
and node.attrname not in SESSION_ONLY_METHODS
) or is_requests_session(node.expr):
return True
if isinstance(node, nodes.Name):
_, assigns = node.lookup(node.name)
for assign in assigns:
if (
isinstance(assign, nodes.ImportFrom)
and assign.modname in REQUESTS_API_MODULES
and assign.real_name(node.name) in HTTP_METHOD_FUNCTIONS
):
return True
if hasattr(assign, 'assign_type'):
assign = assign.assign_type()
if isinstance(assign, nodes.Assign) and is_requests_func(assign.value):
return True
return False
def _set_state_on_block_lines(
self,
msgs_store: MessageDefinitionStore,
node: nodes.NodeNG,
msg: MessageDefinition,
msg_state: dict[int, bool],
) -> None:
"""Recursively walk (depth first) AST to collect block level options
line numbers and set the state correctly.
"""
for child in node.get_children():
self._set_state_on_block_lines(msgs_store, child, msg, msg_state)
# first child line number used to distinguish between disable
# which are the first child of scoped node with those defined later.
# For instance in the code below:
#
# 1. def meth8(self):
# 2. """test late disabling"""
# 3. pylint: disable=not-callable, useless-suppression
# 4. print(self.blip)
# 5. pylint: disable=no-member, useless-suppression
# 6. print(self.bla)
#
# E1102 should be disabled from line 1 to 6 while E1101 from line 5 to 6
#
# this is necessary to disable locally messages applying to class /
# function using their fromlineno
if (isinstance(node, (nodes.Module, nodes.ClassDef, nodes.FunctionDef))
and node.body):
firstchildlineno = node.body[0].fromlineno
else:
firstchildlineno = node.tolineno
self._set_message_state_in_block(msg, msg_state, node,
firstchildlineno)
def _strip_import(cnode: nc.NodeNG, mnode: nc.NodeNG) -> None:
if isinstance(cnode, (astroid.Import, astroid.ImportFrom)):
for name, val in list(mnode.locals.items()):
if cnode in val:
# Pull us out of the list.
valnew = [v for v in val if v is not cnode]
if valnew:
mnode.locals[name] = valnew
else:
del mnode.locals[name]
def _is_float_nan(node: nodes.NodeNG) -> bool:
try:
if isinstance(node, nodes.Call) and len(node.args) == 1:
if (
node.args[0].value.lower() == "nan"
and node.inferred()[0].pytype() == "builtins.float"
):
return True
return False
except AttributeError:
return False
def is_requests_api_module(node: NodeNG) -> bool:
"""True if node represents the requests or requests.api module."""
if isinstance(node, (nodes.Name, nodes.Expr)):
_, assigns = node.lookup(node.name)
for assign in assigns:
if (
isinstance(assign, (nodes.Import, nodes.ImportFrom))
and assign.real_name(node.name) in REQUESTS_API_MODULES
):
return True
return False
def visit_default(self, node: nodes.NodeNG) -> None:
"""Check the node line number and check it if not yet done."""
if not node.is_statement:
return
if not node.root().pure_python:
return
prev_sibl = node.previous_sibling()
if prev_sibl is not None:
prev_line = prev_sibl.fromlineno
# The line on which a 'finally': occurs in a 'try/finally'
# is not directly represented in the AST. We infer it
# by taking the last line of the body and adding 1, which
# should be the line of finally:
elif (isinstance(node.parent, nodes.TryFinally)
and node in node.parent.finalbody):
prev_line = node.parent.body[0].tolineno + 1
elif isinstance(node.parent, nodes.Module):
prev_line = 0
else:
prev_line = node.parent.statement(future=True).fromlineno
line = node.fromlineno
assert line, node
if prev_line == line and self._visited_lines.get(line) != 2:
self._check_multi_statement_line(node, line)
return
if line in self._visited_lines:
return
try:
tolineno = node.blockstart_tolineno
except AttributeError:
tolineno = node.tolineno
assert tolineno, node
lines = []
for line in range(line, tolineno + 1):
self._visited_lines[line] = 1
try:
lines.append(self._lines[line].rstrip())
except KeyError:
lines.append("")
def transform(node: NodeNG,
infer_function: InferFn = infer_function) -> NodeNG:
if (raise_on_overwrite and node._explicit_inference is not None
and node._explicit_inference is not infer_function):
raise InferenceOverwriteError(
"Inference already set to {existing_inference}. "
"Trying to overwrite with {new_inference} for {node}".format(
existing_inference=infer_function,
new_inference=node._explicit_inference,
node=node,
))
# pylint: disable=no-value-for-parameter
node._explicit_inference = _inference_tip_cached(infer_function)
return node
def get_module_and_frameid(node: nodes.NodeNG) -> Tuple[str, str]:
"""Return the module name and the frame id in the module."""
frame = node.frame(future=True)
module, obj = "", []
while frame:
if isinstance(frame, Module):
module = frame.name
else:
obj.append(getattr(frame, "name", "<lambda>"))
try:
frame = frame.parent.frame(future=True)
except AttributeError:
break
obj.reverse()
return module, ".".join(obj)
def visit(self, node: nodes.NodeNG) -> Any:
"""Launch the visit starting from the given node."""
if node in self._visited:
return None
self._visited.add(node)
methods = self.get_callbacks(node)
if methods[0] is not None:
methods[0](node)
if hasattr(node, "locals"): # skip Instance and other proxy
for local_node in node.values():
self.visit(local_node)
if methods[1] is not None:
return methods[1](node)
return None
def is_session_class(node: NodeNG) -> bool:
"""True if node represents the requests.Session class."""
try:
for inferred in node.infer():
if (
isinstance(inferred, nodes.ClassDef)
and inferred.name == SESSION_CLASS_NAME
and isinstance(inferred.parent, nodes.Module)
and inferred.parent.name == SESSION_MODULE
):
return True
except InferenceError:
pass
return False
def _check_key_in_kwargs(unpacked: NodeNG, key: str) -> bool:
"""Given a **kwargs node in a function call, tries to check presence of a key."""
try:
for inferred in unpacked.infer():
if (
isinstance(inferred, nodes.Dict)
and inferred.items
and not _check_key_in_dict(inferred, key)
):
# only if we know that it is a dict and astroid inferred some values
return False
except InferenceError:
pass
return True
def _lookup(node: NodeNG) -> List[NodeNG]:
"""Given a name or attribute node, returns the assignments to that name/attr."""
if isinstance(node, nodes.Name):
return node.lookup(node.name)[1]
if isinstance(node, nodes.Attribute):
try:
obj = next(node.expr.infer())
except InferenceError:
return []
if isinstance(obj, bases.Instance):
try:
return obj.getattr(node.attrname)
except AttributeInferenceError:
return []
return []
def func_annotations_filter(node: nc.NodeNG) -> nc.NodeNG:
"""Filter annotated function args/retvals.
This accounts for deferred evaluation available in in Python 3.7+
via 'from __future__ import annotations'. In this case we don't
want Pylint to complain about missing symbols in annotations when
they aren't actually needed at runtime.
"""
# Only do this if deferred annotations are on.
if not using_future_annotations(node):
return node
# Wipe out argument annotations.
# Special-case: certain function decorators *do*
# evaluate annotations at runtime so we want to leave theirs intact.
# This includes functools.singledispatch, ba.dispatchmethod, and
# efro.MessageReceiver.
# Lets just look for a @XXX.register or @XXX.handler decorators for
# now; can get more specific if we get false positives.
if node.decorators is not None:
for dnode in node.decorators.nodes:
if (isinstance(dnode, astroid.nodes.Name)
and dnode.name in {'dispatchmethod', 'singledispatch'}):
return node # Leave annotations intact.
if (isinstance(dnode, astroid.nodes.Attribute)
and dnode.attrname in {'register', 'handler'}):
return node # Leave annotations intact.
node.args.annotations = [None for _ in node.args.args]
node.args.varargannotation = None
node.args.kwargannotation = None
node.args.kwonlyargs_annotations = [None for _ in node.args.kwonlyargs]
node.args.posonlyargs_annotations = [None for _ in node.args.kwonlyargs]
# Wipe out return-value annotation.
if node.returns is not None:
node.returns = None
return node
def func_annotations_filter(node: nc.NodeNG) -> nc.NodeNG:
"""Filter annotated function args/retvals.
This accounts for deferred evaluation available in in Python 3.7+
via 'from __future__ import annotations'. In this case we don't
want Pylint to complain about missing symbols in annotations when
they aren't actually needed at runtime.
"""
# Only do this if deferred annotations are on.
if not using_future_annotations(node):
return node
# Wipe out argument annotations.
# Special-case: functools.singledispatch and ba.dispatchmethod *do*
# evaluate annotations at runtime so we want to leave theirs intact.
# Lets just look for a @XXX.register decorator used by both I guess.
if node.decorators is not None:
for dnode in node.decorators.nodes:
if (isinstance(dnode, astroid.nodes.Name)
and dnode.name in ('dispatchmethod', 'singledispatch')):
return node # Leave annotations intact.
if (isinstance(dnode, astroid.nodes.Attribute)
and dnode.attrname == 'register'):
return node # Leave annotations intact.
node.args.annotations = [None for _ in node.args.args]
node.args.varargannotation = None
node.args.kwargannotation = None
node.args.kwonlyargs_annotations = [None for _ in node.args.kwonlyargs]
node.args.posonlyargs_annotations = [None for _ in node.args.kwonlyargs]
# Wipe out return-value annotation.
if node.returns is not None:
node.returns = None
return node
def class_generics_filter(node: nc.NodeNG) -> nc.NodeNG:
"""Filter generics subscripts out of class declarations."""
# First, quick-out if nothing here should be filtered.
found = False
for base in node.bases:
if _is_strippable_subscript(base):
found = True
if not found:
return node
# Now strip subscripts from base classes.
new_bases: list[nc.NodeNG] = []
for base in node.bases:
if _is_strippable_subscript(base):
new_bases.append(base.value)
base.value.parent = node
else:
new_bases.append(base)
node.bases = new_bases
return node
def _to_literal(node: nodes.NodeNG) -> Any:
# Can raise SyntaxError or ValueError from ast.literal_eval
# Can raise AttributeError from node.as_string() as not all nodes have a visitor
# Is this the stupidest idea or the simplest idea?
return ast.literal_eval(node.as_string())
def _set_message_state_in_block(
self,
msg: MessageDefinition,
lines: dict[int, bool],
node: nodes.NodeNG,
firstchildlineno: int,
) -> None:
"""Set the state of a message in a block of lines."""
first = node.fromlineno
last = node.tolineno
for lineno, state in list(lines.items()):
original_lineno = lineno
if first > lineno or last < lineno:
continue
# Set state for all lines for this block, if the
# warning is applied to nodes.
if msg.scope == WarningScope.NODE:
if lineno > firstchildlineno:
state = True
first_, last_ = node.block_range(lineno)
# pylint: disable=useless-suppression
# For block nodes first_ is their definition line. For example, we
# set the state of line zero for a module to allow disabling
# invalid-name for the module. For example:
# 1. # pylint: disable=invalid-name
# 2. ...
# OR
# 1. """Module docstring"""
# 2. # pylint: disable=invalid-name
# 3. ...
#
# But if we already visited line 0 we don't need to set its state again
# 1. # pylint: disable=invalid-name
# 2. # pylint: enable=invalid-name
# 3. ...
# The state should come from line 1, not from line 2
# Therefore, if the 'fromlineno' is already in the states we just start
# with the lineno we were originally visiting.
# pylint: enable=useless-suppression
if (first_ == node.fromlineno and first_ >= firstchildlineno
and node.fromlineno in self._module_msgs_state.get(
msg.msgid, ())):
first_ = lineno
else:
first_ = lineno
last_ = last
for line in range(first_, last_ + 1):
# Do not override existing entries. This is especially important
# when parsing the states for a scoped node where some line-disables
# have already been parsed.
if ((isinstance(node, nodes.Module)
and node.fromlineno <= line < lineno) or
(not isinstance(node, nodes.Module)
and node.fromlineno < line < lineno)
) and line in self._module_msgs_state.get(msg.msgid, ()):
continue
if line in lines: # state change in the same block
state = lines[line]
original_lineno = line
# Update suppression mapping
if not state:
self._suppression_mapping[(msg.msgid,
line)] = original_lineno
else:
self._suppression_mapping.pop((msg.msgid, line), None)
# Update message state for respective line
try:
self._module_msgs_state[msg.msgid][line] = state
except KeyError:
self._module_msgs_state[msg.msgid] = {line: state}
del lines[lineno]
def _filter_stmts(base_node: nodes.NodeNG, stmts, frame, offset):
"""Filter the given list of statements to remove ignorable statements.
If base_node is not a frame itself and the name is found in the inner
frame locals, statements will be filtered to remove ignorable
statements according to base_node's location.
:param stmts: The statements to filter.
:type stmts: list(nodes.NodeNG)
:param frame: The frame that all of the given statements belong to.
:type frame: nodes.NodeNG
:param offset: The line offset to filter statements up to.
:type offset: int
:returns: The filtered statements.
:rtype: list(nodes.NodeNG)
"""
# if offset == -1, my actual frame is not the inner frame but its parent
#
# class A(B): pass
#
# we need this to resolve B correctly
if offset == -1:
myframe = base_node.frame().parent.frame()
else:
myframe = base_node.frame()
# If the frame of this node is the same as the statement
# of this node, then the node is part of a class or
# a function definition and the frame of this node should be the
# the upper frame, not the frame of the definition.
# For more information why this is important,
# see Pylint issue #295.
# For example, for 'b', the statement is the same
# as the frame / scope:
#
# def test(b=1):
# ...
if (base_node.parent and base_node.statement(future=True) is myframe
and myframe.parent):
myframe = myframe.parent.frame()
mystmt: Optional[nodes.Statement] = None
if base_node.parent:
mystmt = base_node.statement(future=True)
# line filtering if we are in the same frame
#
# take care node may be missing lineno information (this is the case for
# nodes inserted for living objects)
if myframe is frame and mystmt and mystmt.fromlineno is not None:
assert mystmt.fromlineno is not None, mystmt
mylineno = mystmt.fromlineno + offset
else:
# disabling lineno filtering
mylineno = 0
_stmts = []
_stmt_parents = []
statements = _get_filtered_node_statements(base_node, stmts)
for node, stmt in statements:
# line filtering is on and we have reached our location, break
if stmt.fromlineno and stmt.fromlineno > mylineno > 0:
break
# Ignore decorators with the same name as the
# decorated function
# Fixes issue #375
if mystmt is stmt and _is_from_decorator(base_node):
continue
assert hasattr(node, "assign_type"), (
node,
node.scope(),
node.scope().locals,
)
assign_type = node.assign_type()
if node.has_base(base_node):
break
_stmts, done = assign_type._get_filtered_stmts(base_node, node, _stmts,
mystmt)
if done:
break
optional_assign = assign_type.optional_assign
if optional_assign and assign_type.parent_of(base_node):
# we are inside a loop, loop var assignment is hiding previous
# assignment
_stmts = [node]
_stmt_parents = [stmt.parent]
continue
if isinstance(assign_type, nodes.NamedExpr):
# If the NamedExpr is in an if statement we do some basic control flow inference
if_parent = _get_if_statement_ancestor(assign_type)
if if_parent:
# If the if statement is within another if statement we append the node
# to possible statements
if _get_if_statement_ancestor(if_parent):
optional_assign = False
_stmts.append(node)
_stmt_parents.append(stmt.parent)
# If the if statement is first-level and not within an orelse block
# we know that it will be evaluated
elif not if_parent.is_orelse:
_stmts = [node]
_stmt_parents = [stmt.parent]
# Else we do not known enough about the control flow to be 100% certain
# and we append to possible statements
else:
_stmts.append(node)
_stmt_parents.append(stmt.parent)
else:
_stmts = [node]
_stmt_parents = [stmt.parent]
# XXX comment various branches below!!!
try:
pindex = _stmt_parents.index(stmt.parent)
except ValueError:
pass
else:
# we got a parent index, this means the currently visited node
# is at the same block level as a previously visited node
if _stmts[pindex].assign_type().parent_of(assign_type):
# both statements are not at the same block level
continue
# if currently visited node is following previously considered
# assignment and both are not exclusive, we can drop the
# previous one. For instance in the following code ::
#
# if a:
# x = 1
# else:
# x = 2
# print x
#
# we can't remove neither x = 1 nor x = 2 when looking for 'x'
# of 'print x'; while in the following ::
#
# x = 1
# x = 2
# print x
#
# we can remove x = 1 when we see x = 2
#
# moreover, on loop assignment types, assignment won't
# necessarily be done if the loop has no iteration, so we don't
# want to clear previous assignments if any (hence the test on
# optional_assign)
if not (optional_assign
or nodes.are_exclusive(_stmts[pindex], node)):
del _stmt_parents[pindex]
del _stmts[pindex]
# If base_node and node are exclusive, then we can ignore node
if nodes.are_exclusive(base_node, node):
continue
# An AssignName node overrides previous assignments if:
# 1. node's statement always assigns
# 2. node and base_node are in the same block (i.e., has the same parent as base_node)
if isinstance(node, (nodes.NamedExpr, nodes.AssignName)):
if isinstance(stmt, nodes.ExceptHandler):
# If node's statement is an ExceptHandler, then it is the variable
# bound to the caught exception. If base_node is not contained within
# the exception handler block, node should override previous assignments;
# otherwise, node should be ignored, as an exception variable
# is local to the handler block.
if stmt.parent_of(base_node):
_stmts = []
_stmt_parents = []
else:
continue
elif not optional_assign and mystmt and stmt.parent is mystmt.parent:
_stmts = []
_stmt_parents = []
elif isinstance(node, nodes.DelName):
# Remove all previously stored assignments
_stmts = []
_stmt_parents = []
continue
# Add the new assignment
_stmts.append(node)
if isinstance(node, nodes.Arguments) or isinstance(
node.parent, nodes.Arguments):
# Special case for _stmt_parents when node is a function parameter;
# in this case, stmt is the enclosing FunctionDef, which is what we
# want to add to _stmt_parents, not stmt.parent. This case occurs when
# node is an Arguments node (representing varargs or kwargs parameter),
# and when node.parent is an Arguments node (other parameters).
# See issue #180.
_stmt_parents.append(stmt)
else:
_stmt_parents.append(stmt.parent)
return _stmts
def _get_if_statement_ancestor(node: nodes.NodeNG) -> Optional[nodes.If]:
"""Return the first parent node that is an If node (or None)"""
for parent in node.node_ancestors():
if isinstance(parent, nodes.If):
return parent
return None
def var_annotations_filter(node: nc.NodeNG) -> nc.NodeNG:
"""Filter annotated function variable assigns.
This accounts for deferred evaluation.
"""
# pylint: disable=too-many-branches
# pylint: disable=too-many-nested-blocks
if using_future_annotations(node):
# Future behavior:
# Annotated assigns under functions are not evaluated.
# Class and module vars are normally not either. However we
# do evaluate if we come across an 'ioprepped' dataclass
# decorator. (the 'ioprepped' decorator explicitly evaluates
# dataclass annotations).
fnode = node
willeval = False
while fnode is not None:
if isinstance(fnode, astroid.ClassDef):
if fnode.decorators is not None:
found_ioprepped = False
for dec in fnode.decorators.nodes:
# Look for dataclassio.ioprepped.
if (isinstance(dec, astroid.nodes.Attribute) and
dec.attrname in {'ioprepped', 'will_ioprep'}
and isinstance(dec.expr, astroid.nodes.Name)
and dec.expr.name == 'dataclassio'):
found_ioprepped = True
break
# Look for simply 'ioprepped'.
if (isinstance(dec, astroid.nodes.Name)
and dec.name in {'ioprepped', 'will_ioprep'}):
found_ioprepped = True
break
if found_ioprepped:
willeval = True
break
fnode = fnode.parent
else:
# Legacy behavior:
# Annotated assigns under functions are not evaluated,
# but class or module vars are.
fnode = node
willeval = True
while fnode is not None:
if isinstance(fnode,
(astroid.FunctionDef, astroid.AsyncFunctionDef)):
willeval = False
break
if isinstance(fnode, astroid.ClassDef):
willeval = True
break
fnode = fnode.parent
# If this annotation won't be eval'ed, replace it with a dummy string.
if not willeval:
dummyval = astroid.Const(parent=node, value='dummyval')
node.annotation = dummyval
return node
def default(self, node: nodes.NodeNG, *args: Any) -> None:
for child in node.get_children():
self.dispatch(child, *args)
def _collect_block_lines(
self,
msgs_store: "MessageDefinitionStore",
node: nodes.NodeNG,
msg_state: MessageStateDict,
) -> None:
"""Recursively walk (depth first) AST to collect block level options
line numbers.
"""
for child in node.get_children():
self._collect_block_lines(msgs_store, child, msg_state)
first = node.fromlineno
last = node.tolineno
# first child line number used to distinguish between disable
# which are the first child of scoped node with those defined later.
# For instance in the code below:
#
# 1. def meth8(self):
# 2. """test late disabling"""
# 3. pylint: disable=not-callable, useless-suppression
# 4. print(self.blip)
# 5. pylint: disable=no-member, useless-suppression
# 6. print(self.bla)
#
# E1102 should be disabled from line 1 to 6 while E1101 from line 5 to 6
#
# this is necessary to disable locally messages applying to class /
# function using their fromlineno
if (
isinstance(node, (nodes.Module, nodes.ClassDef, nodes.FunctionDef))
and node.body
):
firstchildlineno = node.body[0].fromlineno
else:
firstchildlineno = last
for msgid, lines in msg_state.items():
for lineno, state in list(lines.items()):
original_lineno = lineno
if first > lineno or last < lineno:
continue
# Set state for all lines for this block, if the
# warning is applied to nodes.
message_definitions = msgs_store.get_message_definitions(msgid)
for message_definition in message_definitions:
if message_definition.scope == WarningScope.NODE:
if lineno > firstchildlineno:
state = True
first_, last_ = node.block_range(lineno)
else:
first_ = lineno
last_ = last
for line in range(first_, last_ + 1):
# do not override existing entries
if line in self._module_msgs_state.get(msgid, ()):
continue
if line in lines: # state change in the same block
state = lines[line]
original_lineno = line
if not state:
self._suppression_mapping[(msgid, line)] = original_lineno
try:
self._module_msgs_state[msgid][line] = state
except KeyError:
self._module_msgs_state[msgid] = {line: state}
del lines[lineno]
def _msg_postponed_eval_hint(self, node: nodes.NodeNG) -> str:
"""Message hint if postponed evaluation isn't enabled."""
if self._py310_plus or "annotations" in node.root().future_imports:
return ""
return ". Add 'from __future__ import annotations' as well"
def _check_singleton_comparison(
self,
left_value: nodes.NodeNG,
right_value: nodes.NodeNG,
root_node: nodes.Compare,
checking_for_absence: bool = False,
) -> None:
"""Check if == or != is being used to compare a singleton value."""
singleton_values = (True, False, None)
def _is_singleton_const(node: nodes.NodeNG) -> bool:
return isinstance(node, nodes.Const) and any(
node.value is value for value in singleton_values
)
if _is_singleton_const(left_value):
singleton, other_value = left_value.value, right_value
elif _is_singleton_const(right_value):
singleton, other_value = right_value.value, left_value
else:
return
singleton_comparison_example = {False: "'{} is {}'", True: "'{} is not {}'"}
# True/False singletons have a special-cased message in case the user is
# mistakenly using == or != to check for truthiness
if singleton in {True, False}:
suggestion_template = (
"{} if checking for the singleton value {}, or {} if testing for {}"
)
truthiness_example = {False: "not {}", True: "{}"}
truthiness_phrase = {True: "truthiness", False: "falsiness"}
# Looks for comparisons like x == True or x != False
checking_truthiness = singleton is not checking_for_absence
suggestion = suggestion_template.format(
singleton_comparison_example[checking_for_absence].format(
left_value.as_string(), right_value.as_string()
),
singleton,
(
"'bool({})'"
if not utils.is_test_condition(root_node) and checking_truthiness
else "'{}'"
).format(
truthiness_example[checking_truthiness].format(
other_value.as_string()
)
),
truthiness_phrase[checking_truthiness],
)
else:
suggestion = singleton_comparison_example[checking_for_absence].format(
left_value.as_string(), right_value.as_string()
)
self.add_message(
"singleton-comparison",
node=root_node,
args=(f"'{root_node.as_string()}'", suggestion),
)