/usr/lib/python3/dist-packages/pyflakes/checker.py is in pyflakes 0.8.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 | """
Main module.
Implement the central Checker class.
Also, it models the Bindings and Scopes.
"""
import doctest
import os
import sys
PY2 = sys.version_info < (3, 0)
PY32 = sys.version_info < (3, 3) # Python 2.5 to 3.2
PY33 = sys.version_info < (3, 4) # Python 2.5 to 3.3
builtin_vars = dir(__import__('__builtin__' if PY2 else 'builtins'))
try:
import ast
except ImportError: # Python 2.5
import _ast as ast
if 'decorator_list' not in ast.ClassDef._fields:
# Patch the missing attribute 'decorator_list'
ast.ClassDef.decorator_list = ()
ast.FunctionDef.decorator_list = property(lambda s: s.decorators)
from pyflakes import messages
if PY2:
def getNodeType(node_class):
# workaround str.upper() which is locale-dependent
return str(unicode(node_class.__name__).upper())
else:
def getNodeType(node_class):
return node_class.__name__.upper()
# Python >= 3.3 uses ast.Try instead of (ast.TryExcept + ast.TryFinally)
if PY32:
def getAlternatives(n):
if isinstance(n, (ast.If, ast.TryFinally)):
return [n.body]
if isinstance(n, ast.TryExcept):
return [n.body + n.orelse] + [[hdl] for hdl in n.handlers]
else:
def getAlternatives(n):
if isinstance(n, ast.If):
return [n.body]
if isinstance(n, ast.Try):
return [n.body + n.orelse] + [[hdl] for hdl in n.handlers]
class _FieldsOrder(dict):
"""Fix order of AST node fields."""
def _get_fields(self, node_class):
# handle iter before target, and generators before element
fields = node_class._fields
if 'iter' in fields:
key_first = 'iter'.find
elif 'generators' in fields:
key_first = 'generators'.find
else:
key_first = 'value'.find
return tuple(sorted(fields, key=key_first, reverse=True))
def __missing__(self, node_class):
self[node_class] = fields = self._get_fields(node_class)
return fields
def iter_child_nodes(node, omit=None, _fields_order=_FieldsOrder()):
"""
Yield all direct child nodes of *node*, that is, all fields that
are nodes and all items of fields that are lists of nodes.
"""
for name in _fields_order[node.__class__]:
if name == omit:
continue
field = getattr(node, name, None)
if isinstance(field, ast.AST):
yield field
elif isinstance(field, list):
for item in field:
yield item
class Binding(object):
"""
Represents the binding of a value to a name.
The checker uses this to keep track of which names have been bound and
which names have not. See L{Assignment} for a special type of binding that
is checked with stricter rules.
@ivar used: pair of (L{Scope}, line-number) indicating the scope and
line number that this binding was last used
"""
def __init__(self, name, source):
self.name = name
self.source = source
self.used = False
def __str__(self):
return self.name
def __repr__(self):
return '<%s object %r from line %r at 0x%x>' % (self.__class__.__name__,
self.name,
self.source.lineno,
id(self))
def redefines(self, other):
return isinstance(other, Definition) and self.name == other.name
class Definition(Binding):
"""
A binding that defines a function or a class.
"""
class Importation(Definition):
"""
A binding created by an import statement.
@ivar fullName: The complete name given to the import statement,
possibly including multiple dotted components.
@type fullName: C{str}
"""
def __init__(self, name, source):
self.fullName = name
self.redefined = []
name = name.split('.')[0]
super(Importation, self).__init__(name, source)
def redefines(self, other):
if isinstance(other, Importation):
return self.fullName == other.fullName
return isinstance(other, Definition) and self.name == other.name
class Argument(Binding):
"""
Represents binding a name as an argument.
"""
class Assignment(Binding):
"""
Represents binding a name with an explicit assignment.
The checker will raise warnings for any Assignment that isn't used. Also,
the checker does not consider assignments in tuple/list unpacking to be
Assignments, rather it treats them as simple Bindings.
"""
class FunctionDefinition(Definition):
pass
class ClassDefinition(Definition):
pass
class ExportBinding(Binding):
"""
A binding created by an C{__all__} assignment. If the names in the list
can be determined statically, they will be treated as names for export and
additional checking applied to them.
The only C{__all__} assignment that can be recognized is one which takes
the value of a literal list containing literal strings. For example::
__all__ = ["foo", "bar"]
Names which are imported and not otherwise used but appear in the value of
C{__all__} will not have an unused import warning reported for them.
"""
def __init__(self, name, source, scope):
if '__all__' in scope and isinstance(source, ast.AugAssign):
self.names = list(scope['__all__'].names)
else:
self.names = []
if isinstance(source.value, (ast.List, ast.Tuple)):
for node in source.value.elts:
if isinstance(node, ast.Str):
self.names.append(node.s)
super(ExportBinding, self).__init__(name, source)
class Scope(dict):
importStarred = False # set to True when import * is found
def __repr__(self):
scope_cls = self.__class__.__name__
return '<%s at 0x%x %s>' % (scope_cls, id(self), dict.__repr__(self))
class ClassScope(Scope):
pass
class FunctionScope(Scope):
"""
I represent a name scope for a function.
@ivar globals: Names declared 'global' in this function.
"""
usesLocals = False
alwaysUsed = set(['__tracebackhide__',
'__traceback_info__', '__traceback_supplement__'])
def __init__(self):
super(FunctionScope, self).__init__()
# Simplify: manage the special locals as globals
self.globals = self.alwaysUsed.copy()
self.returnValue = None # First non-empty return
self.isGenerator = False # Detect a generator
def unusedAssignments(self):
"""
Return a generator for the assignments which have not been used.
"""
for name, binding in self.items():
if (not binding.used and name not in self.globals
and not self.usesLocals
and isinstance(binding, Assignment)):
yield name, binding
class GeneratorScope(Scope):
pass
class ModuleScope(Scope):
pass
# Globally defined names which are not attributes of the builtins module, or
# are only present on some platforms.
_MAGIC_GLOBALS = ['__file__', '__builtins__', 'WindowsError']
def getNodeName(node):
# Returns node.id, or node.name, or None
if hasattr(node, 'id'): # One of the many nodes with an id
return node.id
if hasattr(node, 'name'): # a ExceptHandler node
return node.name
class Checker(object):
"""
I check the cleanliness and sanity of Python code.
@ivar _deferredFunctions: Tracking list used by L{deferFunction}. Elements
of the list are two-tuples. The first element is the callable passed
to L{deferFunction}. The second element is a copy of the scope stack
at the time L{deferFunction} was called.
@ivar _deferredAssignments: Similar to C{_deferredFunctions}, but for
callables which are deferred assignment checks.
"""
nodeDepth = 0
offset = None
traceTree = False
builtIns = set(builtin_vars).union(_MAGIC_GLOBALS)
_customBuiltIns = os.environ.get('PYFLAKES_BUILTINS')
if _customBuiltIns:
builtIns.update(_customBuiltIns.split(','))
del _customBuiltIns
def __init__(self, tree, filename='(none)', builtins=None,
withDoctest='PYFLAKES_DOCTEST' in os.environ):
self._nodeHandlers = {}
self._deferredFunctions = []
self._deferredAssignments = []
self.deadScopes = []
self.messages = []
self.filename = filename
if builtins:
self.builtIns = self.builtIns.union(builtins)
self.withDoctest = withDoctest
self.scopeStack = [ModuleScope()]
self.exceptHandlers = [()]
self.futuresAllowed = True
self.root = tree
self.handleChildren(tree)
self.runDeferred(self._deferredFunctions)
# Set _deferredFunctions to None so that deferFunction will fail
# noisily if called after we've run through the deferred functions.
self._deferredFunctions = None
self.runDeferred(self._deferredAssignments)
# Set _deferredAssignments to None so that deferAssignment will fail
# noisily if called after we've run through the deferred assignments.
self._deferredAssignments = None
del self.scopeStack[1:]
self.popScope()
self.checkDeadScopes()
def deferFunction(self, callable):
"""
Schedule a function handler to be called just before completion.
This is used for handling function bodies, which must be deferred
because code later in the file might modify the global scope. When
`callable` is called, the scope at the time this is called will be
restored, however it will contain any new bindings added to it.
"""
self._deferredFunctions.append((callable, self.scopeStack[:], self.offset))
def deferAssignment(self, callable):
"""
Schedule an assignment handler to be called just after deferred
function handlers.
"""
self._deferredAssignments.append((callable, self.scopeStack[:], self.offset))
def runDeferred(self, deferred):
"""
Run the callables in C{deferred} using their associated scope stack.
"""
for handler, scope, offset in deferred:
self.scopeStack = scope
self.offset = offset
handler()
@property
def scope(self):
return self.scopeStack[-1]
def popScope(self):
self.deadScopes.append(self.scopeStack.pop())
def checkDeadScopes(self):
"""
Look at scopes which have been fully examined and report names in them
which were imported but unused.
"""
for scope in self.deadScopes:
if isinstance(scope.get('__all__'), ExportBinding):
all_names = set(scope['__all__'].names)
if not scope.importStarred and \
os.path.basename(self.filename) != '__init__.py':
# Look for possible mistakes in the export list
undefined = all_names.difference(scope)
for name in undefined:
self.report(messages.UndefinedExport,
scope['__all__'].source, name)
else:
all_names = []
# Look for imported names that aren't used.
for value in scope.values():
if isinstance(value, Importation):
used = value.used or value.name in all_names
if not used:
messg = messages.UnusedImport
self.report(messg, value.source, value.name)
for node in value.redefined:
if isinstance(self.getParent(node), ast.For):
messg = messages.ImportShadowedByLoopVar
elif used:
continue
else:
messg = messages.RedefinedWhileUnused
self.report(messg, node, value.name, value.source)
def pushScope(self, scopeClass=FunctionScope):
self.scopeStack.append(scopeClass())
def report(self, messageClass, *args, **kwargs):
self.messages.append(messageClass(self.filename, *args, **kwargs))
def getParent(self, node):
# Lookup the first parent which is not Tuple, List or Starred
while True:
node = node.parent
if not hasattr(node, 'elts') and not hasattr(node, 'ctx'):
return node
def getCommonAncestor(self, lnode, rnode, stop):
if stop in (lnode, rnode) or not (hasattr(lnode, 'parent') and
hasattr(rnode, 'parent')):
return None
if lnode is rnode:
return lnode
if (lnode.depth > rnode.depth):
return self.getCommonAncestor(lnode.parent, rnode, stop)
if (lnode.depth < rnode.depth):
return self.getCommonAncestor(lnode, rnode.parent, stop)
return self.getCommonAncestor(lnode.parent, rnode.parent, stop)
def descendantOf(self, node, ancestors, stop):
for a in ancestors:
if self.getCommonAncestor(node, a, stop):
return True
return False
def differentForks(self, lnode, rnode):
"""True, if lnode and rnode are located on different forks of IF/TRY"""
ancestor = self.getCommonAncestor(lnode, rnode, self.root)
parts = getAlternatives(ancestor)
if parts:
for items in parts:
if self.descendantOf(lnode, items, ancestor) ^ \
self.descendantOf(rnode, items, ancestor):
return True
return False
def addBinding(self, node, value):
"""
Called when a binding is altered.
- `node` is the statement responsible for the change
- `value` is the new value, a Binding instance
"""
# assert value.source in (node, node.parent):
for scope in self.scopeStack[::-1]:
if value.name in scope:
break
existing = scope.get(value.name)
if existing and not self.differentForks(node, existing.source):
parent_stmt = self.getParent(value.source)
if isinstance(existing, Importation) and isinstance(parent_stmt, ast.For):
self.report(messages.ImportShadowedByLoopVar,
node, value.name, existing.source)
elif scope is self.scope:
if (isinstance(parent_stmt, ast.comprehension) and
not isinstance(self.getParent(existing.source),
(ast.For, ast.comprehension))):
self.report(messages.RedefinedInListComp,
node, value.name, existing.source)
elif not existing.used and value.redefines(existing):
self.report(messages.RedefinedWhileUnused,
node, value.name, existing.source)
elif isinstance(existing, Importation) and value.redefines(existing):
existing.redefined.append(node)
self.scope[value.name] = value
def getNodeHandler(self, node_class):
try:
return self._nodeHandlers[node_class]
except KeyError:
nodeType = getNodeType(node_class)
self._nodeHandlers[node_class] = handler = getattr(self, nodeType)
return handler
def handleNodeLoad(self, node):
name = getNodeName(node)
if not name:
return
# try local scope
try:
self.scope[name].used = (self.scope, node)
except KeyError:
pass
else:
return
scopes = [scope for scope in self.scopeStack[:-1]
if isinstance(scope, (FunctionScope, ModuleScope))]
if isinstance(self.scope, GeneratorScope) and scopes[-1] != self.scopeStack[-2]:
scopes.append(self.scopeStack[-2])
# try enclosing function scopes and global scope
importStarred = self.scope.importStarred
for scope in reversed(scopes):
importStarred = importStarred or scope.importStarred
try:
scope[name].used = (self.scope, node)
except KeyError:
pass
else:
return
# look in the built-ins
if importStarred or name in self.builtIns:
return
if name == '__path__' and os.path.basename(self.filename) == '__init__.py':
# the special name __path__ is valid only in packages
return
# protected with a NameError handler?
if 'NameError' not in self.exceptHandlers[-1]:
self.report(messages.UndefinedName, node, name)
def handleNodeStore(self, node):
name = getNodeName(node)
if not name:
return
# if the name hasn't already been defined in the current scope
if isinstance(self.scope, FunctionScope) and name not in self.scope:
# for each function or module scope above us
for scope in self.scopeStack[:-1]:
if not isinstance(scope, (FunctionScope, ModuleScope)):
continue
# if the name was defined in that scope, and the name has
# been accessed already in the current scope, and hasn't
# been declared global
used = name in scope and scope[name].used
if used and used[0] is self.scope and name not in self.scope.globals:
# then it's probably a mistake
self.report(messages.UndefinedLocal,
scope[name].used[1], name, scope[name].source)
break
parent_stmt = self.getParent(node)
if isinstance(parent_stmt, (ast.For, ast.comprehension)) or (
parent_stmt != node.parent and
not self.isLiteralTupleUnpacking(parent_stmt)):
binding = Binding(name, node)
elif name == '__all__' and isinstance(self.scope, ModuleScope):
binding = ExportBinding(name, node.parent, self.scope)
else:
binding = Assignment(name, node)
if name in self.scope:
binding.used = self.scope[name].used
self.addBinding(node, binding)
def handleNodeDelete(self, node):
name = getNodeName(node)
if not name:
return
if isinstance(self.scope, FunctionScope) and name in self.scope.globals:
self.scope.globals.remove(name)
else:
try:
del self.scope[name]
except KeyError:
self.report(messages.UndefinedName, node, name)
def handleChildren(self, tree, omit=None):
for node in iter_child_nodes(tree, omit=omit):
self.handleNode(node, tree)
def isLiteralTupleUnpacking(self, node):
if isinstance(node, ast.Assign):
for child in node.targets + [node.value]:
if not hasattr(child, 'elts'):
return False
return True
def isDocstring(self, node):
"""
Determine if the given node is a docstring, as long as it is at the
correct place in the node tree.
"""
return isinstance(node, ast.Str) or (isinstance(node, ast.Expr) and
isinstance(node.value, ast.Str))
def getDocstring(self, node):
if isinstance(node, ast.Expr):
node = node.value
if not isinstance(node, ast.Str):
return (None, None)
# Computed incorrectly if the docstring has backslash
doctest_lineno = node.lineno - node.s.count('\n') - 1
return (node.s, doctest_lineno)
def handleNode(self, node, parent):
if node is None:
return
if self.offset and getattr(node, 'lineno', None) is not None:
node.lineno += self.offset[0]
node.col_offset += self.offset[1]
if self.traceTree:
print(' ' * self.nodeDepth + node.__class__.__name__)
if self.futuresAllowed and not (isinstance(node, ast.ImportFrom) or
self.isDocstring(node)):
self.futuresAllowed = False
self.nodeDepth += 1
node.depth = self.nodeDepth
node.parent = parent
try:
handler = self.getNodeHandler(node.__class__)
handler(node)
finally:
self.nodeDepth -= 1
if self.traceTree:
print(' ' * self.nodeDepth + 'end ' + node.__class__.__name__)
_getDoctestExamples = doctest.DocTestParser().get_examples
def handleDoctests(self, node):
try:
(docstring, node_lineno) = self.getDocstring(node.body[0])
examples = docstring and self._getDoctestExamples(docstring)
except (ValueError, IndexError):
# e.g. line 6 of the docstring for <string> has inconsistent
# leading whitespace: ...
return
if not examples:
return
node_offset = self.offset or (0, 0)
self.pushScope()
underscore_in_builtins = '_' in self.builtIns
if not underscore_in_builtins:
self.builtIns.add('_')
for example in examples:
try:
tree = compile(example.source, "<doctest>", "exec", ast.PyCF_ONLY_AST)
except SyntaxError:
e = sys.exc_info()[1]
position = (node_lineno + example.lineno + e.lineno,
example.indent + 4 + (e.offset or 0))
self.report(messages.DoctestSyntaxError, node, position)
else:
self.offset = (node_offset[0] + node_lineno + example.lineno,
node_offset[1] + example.indent + 4)
self.handleChildren(tree)
self.offset = node_offset
if not underscore_in_builtins:
self.builtIns.remove('_')
self.popScope()
def ignore(self, node):
pass
# "stmt" type nodes
DELETE = PRINT = FOR = WHILE = IF = WITH = WITHITEM = RAISE = \
TRYFINALLY = ASSERT = EXEC = EXPR = ASSIGN = handleChildren
CONTINUE = BREAK = PASS = ignore
# "expr" type nodes
BOOLOP = BINOP = UNARYOP = IFEXP = DICT = SET = \
COMPARE = CALL = REPR = ATTRIBUTE = SUBSCRIPT = LIST = TUPLE = \
STARRED = NAMECONSTANT = handleChildren
NUM = STR = BYTES = ELLIPSIS = ignore
# "slice" type nodes
SLICE = EXTSLICE = INDEX = handleChildren
# expression contexts are node instances too, though being constants
LOAD = STORE = DEL = AUGLOAD = AUGSTORE = PARAM = ignore
# same for operators
AND = OR = ADD = SUB = MULT = DIV = MOD = POW = LSHIFT = RSHIFT = \
BITOR = BITXOR = BITAND = FLOORDIV = INVERT = NOT = UADD = USUB = \
EQ = NOTEQ = LT = LTE = GT = GTE = IS = ISNOT = IN = NOTIN = ignore
# additional node types
LISTCOMP = COMPREHENSION = KEYWORD = handleChildren
def GLOBAL(self, node):
"""
Keep track of globals declarations.
"""
if isinstance(self.scope, FunctionScope):
self.scope.globals.update(node.names)
NONLOCAL = GLOBAL
def GENERATOREXP(self, node):
self.pushScope(GeneratorScope)
self.handleChildren(node)
self.popScope()
DICTCOMP = SETCOMP = GENERATOREXP
def NAME(self, node):
"""
Handle occurrence of Name (which can be a load/store/delete access.)
"""
# Locate the name in locals / function / globals scopes.
if isinstance(node.ctx, (ast.Load, ast.AugLoad)):
self.handleNodeLoad(node)
if (node.id == 'locals' and isinstance(self.scope, FunctionScope)
and isinstance(node.parent, ast.Call)):
# we are doing locals() call in current scope
self.scope.usesLocals = True
elif isinstance(node.ctx, (ast.Store, ast.AugStore)):
self.handleNodeStore(node)
elif isinstance(node.ctx, ast.Del):
self.handleNodeDelete(node)
else:
# must be a Param context -- this only happens for names in function
# arguments, but these aren't dispatched through here
raise RuntimeError("Got impossible expression context: %r" % (node.ctx,))
def RETURN(self, node):
if node.value and not self.scope.returnValue:
self.scope.returnValue = node.value
self.handleNode(node.value, node)
def YIELD(self, node):
self.scope.isGenerator = True
self.handleNode(node.value, node)
YIELDFROM = YIELD
def FUNCTIONDEF(self, node):
for deco in node.decorator_list:
self.handleNode(deco, node)
self.LAMBDA(node)
self.addBinding(node, FunctionDefinition(node.name, node))
if self.withDoctest:
self.deferFunction(lambda: self.handleDoctests(node))
def LAMBDA(self, node):
args = []
annotations = []
if PY2:
def addArgs(arglist):
for arg in arglist:
if isinstance(arg, ast.Tuple):
addArgs(arg.elts)
else:
args.append(arg.id)
addArgs(node.args.args)
defaults = node.args.defaults
else:
for arg in node.args.args + node.args.kwonlyargs:
args.append(arg.arg)
annotations.append(arg.annotation)
defaults = node.args.defaults + node.args.kw_defaults
# Only for Python3 FunctionDefs
is_py3_func = hasattr(node, 'returns')
for arg_name in ('vararg', 'kwarg'):
wildcard = getattr(node.args, arg_name)
if not wildcard:
continue
args.append(wildcard if PY33 else wildcard.arg)
if is_py3_func:
if PY33: # Python 2.5 to 3.3
argannotation = arg_name + 'annotation'
annotations.append(getattr(node.args, argannotation))
else: # Python >= 3.4
annotations.append(wildcard.annotation)
if is_py3_func:
annotations.append(node.returns)
if len(set(args)) < len(args):
for (idx, arg) in enumerate(args):
if arg in args[:idx]:
self.report(messages.DuplicateArgument, node, arg)
for child in annotations + defaults:
if child:
self.handleNode(child, node)
def runFunction():
self.pushScope()
for name in args:
self.addBinding(node, Argument(name, node))
if isinstance(node.body, list):
# case for FunctionDefs
for stmt in node.body:
self.handleNode(stmt, node)
else:
# case for Lambdas
self.handleNode(node.body, node)
def checkUnusedAssignments():
"""
Check to see if any assignments have not been used.
"""
for name, binding in self.scope.unusedAssignments():
self.report(messages.UnusedVariable, binding.source, name)
self.deferAssignment(checkUnusedAssignments)
if PY32:
def checkReturnWithArgumentInsideGenerator():
"""
Check to see if there is any return statement with
arguments but the function is a generator.
"""
if self.scope.isGenerator and self.scope.returnValue:
self.report(messages.ReturnWithArgsInsideGenerator,
self.scope.returnValue)
self.deferAssignment(checkReturnWithArgumentInsideGenerator)
self.popScope()
self.deferFunction(runFunction)
def CLASSDEF(self, node):
"""
Check names used in a class definition, including its decorators, base
classes, and the body of its definition. Additionally, add its name to
the current scope.
"""
for deco in node.decorator_list:
self.handleNode(deco, node)
for baseNode in node.bases:
self.handleNode(baseNode, node)
if not PY2:
for keywordNode in node.keywords:
self.handleNode(keywordNode, node)
self.pushScope(ClassScope)
if self.withDoctest:
self.deferFunction(lambda: self.handleDoctests(node))
for stmt in node.body:
self.handleNode(stmt, node)
self.popScope()
self.addBinding(node, ClassDefinition(node.name, node))
def AUGASSIGN(self, node):
self.handleNodeLoad(node.target)
self.handleNode(node.value, node)
self.handleNode(node.target, node)
def IMPORT(self, node):
for alias in node.names:
name = alias.asname or alias.name
importation = Importation(name, node)
self.addBinding(node, importation)
def IMPORTFROM(self, node):
if node.module == '__future__':
if not self.futuresAllowed:
self.report(messages.LateFutureImport,
node, [n.name for n in node.names])
else:
self.futuresAllowed = False
for alias in node.names:
if alias.name == '*':
self.scope.importStarred = True
self.report(messages.ImportStarUsed, node, node.module)
continue
name = alias.asname or alias.name
importation = Importation(name, node)
if node.module == '__future__':
importation.used = (self.scope, node)
self.addBinding(node, importation)
def TRY(self, node):
handler_names = []
# List the exception handlers
for handler in node.handlers:
if isinstance(handler.type, ast.Tuple):
for exc_type in handler.type.elts:
handler_names.append(getNodeName(exc_type))
elif handler.type:
handler_names.append(getNodeName(handler.type))
# Memorize the except handlers and process the body
self.exceptHandlers.append(handler_names)
for child in node.body:
self.handleNode(child, node)
self.exceptHandlers.pop()
# Process the other nodes: "except:", "else:", "finally:"
self.handleChildren(node, omit='body')
TRYEXCEPT = TRY
def EXCEPTHANDLER(self, node):
# 3.x: in addition to handling children, we must handle the name of
# the exception, which is not a Name node, but a simple string.
if isinstance(node.name, str):
self.handleNodeStore(node)
self.handleChildren(node)
|