1 #!/usr/bin/env python 2 3 """ 4 Inspect source files, obtaining details of classes and attributes. 5 6 Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012 Paul Boddie <paul@boddie.org.uk> 7 8 This program is free software; you can redistribute it and/or modify it under 9 the terms of the GNU General Public License as published by the Free Software 10 Foundation; either version 3 of the License, or (at your option) any later 11 version. 12 13 This program is distributed in the hope that it will be useful, but WITHOUT 14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 15 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 16 details. 17 18 You should have received a copy of the GNU General Public License along with 19 this program. If not, see <http://www.gnu.org/licenses/>. 20 21 -------- 22 23 The results of inspecting a module are as follows: 24 25 Constants 26 --------- 27 28 All constants identified within the code shall be registered. 29 30 Classes 31 ------- 32 33 All global classes shall be registered; local classes (within functions) or 34 nested classes (within classes) are not currently registered. 35 36 Base classes must be detected and constant. 37 38 All classes without bases are made to inherit from __builtins__.object in order 39 to support some standard methods. 40 41 Functions 42 --------- 43 44 All functions and lambda definitions shall be registered. 45 46 Namespaces 47 ---------- 48 49 Modules define their own "global" namespace, within which classes, functions 50 and lambda definitions establish a hierarchy of namespaces. 51 52 Only local, global and built-in namespaces are recognised; closures are not 53 supported. 54 55 Assignments 56 ----------- 57 58 Name assignment and attribute assignment involving modules and classes cause 59 names to be associated with values within namespaces. 60 61 Any assignments within loops are considered to cause the targets of such 62 assignments to provide non-constant values. 63 64 Assignments to names are only really considered to cause the targets of such 65 assignments to provide constant values if the targets reside in class 66 namespaces, subject to the above conditions. 67 68 Assignments to names within functions are not generally considered to cause the 69 targets of such assignments to provide constant values since functions can be 70 invoked many times with different inputs. This affects particularly the 71 definition of functions or lambdas within functions. However, there may be 72 benefits in considering a local to be constant within a single invocation. 73 """ 74 75 from micropython.common import ASTVisitor, operator_functions 76 from micropython.data import * 77 from micropython.errors import * 78 import compiler.ast 79 import sys 80 81 # Program visitors. 82 83 class InspectedModule(ASTVisitor, Module): 84 85 """ 86 An inspected module, providing core details via the Module superclass, but 87 capable of being used as an AST visitor. 88 89 A module can be inspected through the invocation of the following methods in 90 order: 91 92 1. parse 93 2. process 94 3. vacuum 95 4. finalise 96 97 A module importer can be expected to perform these invocations. 98 """ 99 100 def __init__(self, name, importer): 101 102 """ 103 Initialise this visitor with a module 'name' and an 'importer' which is 104 used to provide access to other modules when required. 105 """ 106 107 Module.__init__(self, name, importer) 108 self.visitor = self 109 110 # Import machinery links. 111 112 self.optimisations = self.importer.optimisations 113 self.builtins = self.importer.modules.get("__builtins__") 114 self.loaded = False 115 self.completed = False 116 117 # Current expression state. 118 119 self.expr = None 120 self.in_assignment = False # For slice and subscript handling. 121 122 # Namespace state. 123 124 self.in_method = False # Find instance attributes in all methods. 125 self.in_function = False # Note function presence, affecting definitions. 126 self.in_loop = False # Note loop "membership", affecting assignments. 127 self.namespaces = [] 128 self.functions = [] 129 130 def parse(self, filename): 131 132 "Parse the file having the given 'filename'." 133 134 self.astnode = module = compiler.parseFile(filename) 135 136 # Detect and record imports and globals declared in the module. 137 138 self.process_structure(module) 139 140 def complete(self): 141 if not self.completed: 142 self.completed = True 143 self.process() 144 if self.importer.verbose: 145 print >>sys.stderr, "Completed import of", self.full_name() 146 147 def process(self): 148 return self.process_module(self.astnode) 149 150 def process_module(self, module): 151 152 """ 153 Process the given 'module', visiting module-level code and function 154 code. 155 """ 156 157 # Add __name__ to the namespace. 158 159 self.store("__name__", self._visitConst(self.full_name())) 160 161 # Visit module-level code, also recording global names. 162 163 processed = self.dispatch(module) 164 165 self.finalise_attribute_usage() 166 167 # Visit functions. 168 169 self.process_functions() 170 171 # Add references to other modules declared using the __all__ global. 172 173 if self.has_key("__all__"): 174 all = self["__all__"] 175 if isinstance(all, compiler.ast.List): 176 for n in all.nodes: 177 self.store(n.value, self.importer.add_module(self.name + "." + n.value)) 178 179 return processed 180 181 def process_functions(self): 182 183 """ 184 Process all function bodies. Deferred imports may occur during this 185 process. 186 """ 187 188 # Then, visit each function, recording other names. This happens to 189 # work for lambda definitions inside functions since they are added to 190 # the end of self.functions and are thus visited as the iteration 191 # reaches the end of the original list. 192 193 for node, namespaces in self.functions: 194 self._visitFunctionBody(node, namespaces) 195 namespaces[-1].finalise_attribute_usage() 196 197 def process_structure(self, node): 198 199 """ 200 Within the given 'node', process global declarations, adjusting the 201 module namespace, and import statements, building a module dependency 202 hierarchy. 203 """ 204 205 for n in node.getChildNodes(): 206 207 # Module global detection. 208 209 if isinstance(n, compiler.ast.Global): 210 for name in n.names: 211 212 # Each name may potentially be assigned many times. 213 # We don't try and find out the specifics at this point and 214 # just indicate that the name cannot be relied upon for 215 # various observations. 216 217 self.modify_name(name) 218 219 # Module import declarations. 220 221 elif isinstance(n, compiler.ast.From): 222 223 # Load the mentioned module. 224 225 self.record_import(n.modname, n) 226 227 # Speculatively load modules for names beneath the module. 228 229 for name, alias in n.names: 230 modname = n.modname + "." + name 231 self.record_import(modname, n) 232 233 elif isinstance(n, compiler.ast.Import): 234 235 # Load the mentioned module. 236 237 for name, alias in n.names: 238 self.record_import(name, n) 239 240 # Nodes using operator module functions. 241 242 elif operator_functions.has_key(n.__class__.__name__) or \ 243 isinstance(n, (compiler.ast.AugAssign, compiler.ast.Compare)): 244 245 n._module = self.importer.load("operator") 246 247 else: 248 self.process_structure(n) 249 250 def get_module_paths(self, name): 251 252 """ 253 Return the paths of modules leading to the module having the given 254 'name'. 255 """ 256 257 names = [] 258 parts = [] 259 for part in name.split("."): 260 parts.append(part) 261 names.append(".".join(parts)) 262 return names 263 264 def record_import(self, name, node): 265 266 """ 267 Record an import of a module with the given 'name' occurring at the 268 given 'node'. 269 """ 270 271 module = self.importer.load(name, 1, importer=node) 272 if module and not module.loaded: 273 self.importer.circular_imports.add(module) 274 275 def complete_import(self, name, return_leaf): 276 277 """ 278 Complete the import of the module with the given 'name', returning the 279 module itself if 'return_leaf' is a true value, or returning the root of 280 the module hierarchy if 'return_leaf' is a false value. 281 """ 282 283 top = module = None 284 285 for modname in self.get_module_paths(name): 286 287 # Attempt to get the module, returning None for non-existent 288 # modules. 289 290 try: 291 module = self.importer.get_module(modname) 292 except KeyError: 293 return None 294 295 if module: 296 module.complete() 297 298 if top is None: 299 top = module 300 301 if return_leaf: 302 return module 303 else: 304 return top 305 306 def vacuum(self): 307 308 """ 309 Vacuum the module namespace, removing unreferenced objects and unused 310 names. 311 """ 312 313 if self.should_optimise_unused_objects(): 314 self.vacuum_object(self) 315 316 all_objects = list(self.all_objects) 317 318 for obj in all_objects: 319 self.vacuum_object(obj) 320 321 def vacuum_object(self, obj, delete_all=0): 322 323 "Vacuum the given object 'obj'." 324 325 # Get all constant objects in apparent use. 326 327 if delete_all: 328 obj_objects = set() 329 else: 330 obj_objects = [] 331 for name, attr in obj.items_for_vacuum(): 332 333 # Get constant objects for attributes in use. 334 335 if self.importer.uses_attribute(obj.full_name(), name) and \ 336 attr is not None and attr.is_constant(): 337 338 value = attr.get_value() 339 obj_objects.append(value) 340 341 # Now vacuum unused attributes and objects not in use. 342 343 for name, attr in obj.items_for_vacuum(): 344 345 # Only consider deleting entire unused objects or things accessible 346 # via names which are never used. 347 348 if delete_all or not self.importer.uses_attribute(obj.full_name(), name): 349 obj.vacuum_item(name) 350 351 # Delete any unambiguous attribute value. Such values can only 352 # have been defined within the object and therefore are not 353 # redefined by other code regions. 354 355 if attr is not None and attr.is_constant(): 356 value = attr.get_value() 357 358 # The value must have this object as a parent. 359 # However, it must not be shared by several names. 360 361 if value is not obj and value.parent is obj and \ 362 value in self.all_objects and value not in obj_objects: 363 364 self.all_objects.remove(value) 365 366 # Delete class contents and lambdas from functions. 367 368 self.vacuum_object(value, 1) 369 370 def unfinalise(self): 371 372 "Reset finalised information for the module." 373 374 for obj in self.all_objects: 375 obj.unfinalise_attributes() 376 377 def finalise(self, objtable): 378 379 "Finalise the module." 380 381 for obj in self.all_objects: 382 obj.finalise(objtable) 383 384 self.finalise_users(objtable) 385 386 def add_object(self, obj, any_scope=0): 387 388 """ 389 Record 'obj' if non-local or if the optional 'any_scope' is set to a 390 true value. 391 """ 392 393 if any_scope or not (self.namespaces and isinstance(self.namespaces[-1], Function)): 394 self.all_objects.add(obj) 395 396 # Optimisation tests. 397 398 def should_optimise_unused_objects(self): 399 return "unused_objects" in self.optimisations 400 401 # Namespace methods. 402 403 def in_class(self, namespaces=None): 404 namespaces = namespaces or self.namespaces 405 return len(namespaces) > 1 and isinstance(namespaces[-2], Class) 406 407 def store(self, name, obj): 408 409 "Record attribute or local 'name', storing 'obj'." 410 411 # Store in the module. 412 413 if not self.namespaces: 414 if self.in_loop and self.used_in_scope(name, "builtins"): 415 raise InspectError("Name %r already used as a built-in." % name) 416 else: 417 self.set(name, obj, not self.in_loop) 418 419 # Or store locally. 420 421 else: 422 locals = self.namespaces[-1] 423 424 if self.in_loop and locals.used_in_scope(name, "global") and not name in locals.globals: 425 raise InspectError("Name %r already used as global." % name) 426 elif self.in_loop and locals.used_in_scope(name, "builtins"): 427 raise InspectError("Name %r already used as a built-in." % name) 428 else: 429 locals.set(name, obj, not self.in_loop) 430 431 def store_lambda(self, obj): 432 433 "Store a lambda function 'obj'." 434 435 self.add_object(obj) 436 self.get_namespace().add_lambda(obj) 437 438 def store_module_attr(self, name, module): 439 440 """ 441 Record module attribute 'name' in the given 'module' using the current 442 expression. 443 """ 444 445 module.set(name, self.expr, 0) 446 self.use_specific_attribute(module.full_name(), name) 447 448 def store_class_attr(self, name, cls): 449 450 """ 451 Record class attribute 'name' in the given class 'cls' using the current 452 expression. 453 """ 454 455 cls.set(name, self.expr, 0) 456 self.use_specific_attribute(cls.full_name(), name) 457 458 def store_instance_attr(self, name, tentative=False): 459 460 """ 461 Record instance attribute 'name' in the current class. If 'tentative' is 462 set to a true value, the instance attribute will be discarded if a class 463 attribute is observed. 464 """ 465 466 if self.in_method: 467 468 # Current namespace is the function. 469 # Previous namespace is the class. 470 471 cls = self.namespaces[-2] 472 cls.add_instance_attribute(name, tentative) 473 474 # NOTE: The instance attribute, although defined in a specific 475 # NOTE: class, obviously appears in all descendant classes. 476 477 self.use_specific_attribute(cls.full_name(), name) 478 479 def get_namespace(self): 480 481 "Return the parent (or most recent) namespace currently exposed." 482 483 return (self.namespaces[-1:] or [self])[0] 484 485 def use_name(self, name, node=None, value=None, ns=None): 486 487 """ 488 Use the given 'name' within the current namespace/unit, either in 489 conjunction with a particular object (if 'node' is specified and not 490 None) or unconditionally. 491 """ 492 493 unit = self.get_namespace() 494 495 # Handle attribute usage situations within the current unit. 496 497 if node is not None and isinstance(node, compiler.ast.Name) and ns is unit: 498 self.use_attribute(node.name, name, value) 499 500 # For general name usage, declare usage of the given name from this 501 # particular unit. 502 503 else: 504 self.importer.use_name(name, unit.full_name(), value) 505 506 def use_constant(self, const): 507 508 "Use the given 'const' within the current namespace/unit." 509 510 unit = self.get_namespace() 511 self.importer.use_constant(const, unit.full_name()) 512 513 # Attribute usage methods. 514 # These are convenience methods which refer to the specific namespace's 515 # implementation of these operations. 516 517 def new_branchpoint(self, loop_node=None): 518 self.get_namespace()._new_branchpoint(loop_node) 519 520 def new_branch(self, node): 521 self.get_namespace()._new_branch(node) 522 523 def abandon_branch(self): 524 self.get_namespace()._abandon_branch() 525 526 def suspend_broken_branch(self): 527 self.get_namespace()._suspend_broken_branch() 528 529 def suspend_continuing_branch(self): 530 self.get_namespace()._suspend_continuing_branch() 531 532 def shelve_branch(self): 533 self.get_namespace()._shelve_branch() 534 535 def merge_branches(self): 536 self.get_namespace()._merge_branches() 537 538 def resume_broken_branches(self): 539 self.get_namespace()._resume_broken_branches() 540 541 def resume_continuing_branches(self): 542 self.get_namespace()._resume_continuing_branches() 543 544 def resume_abandoned_branches(self): 545 self.get_namespace()._resume_abandoned_branches() 546 547 def define_attribute_user(self, node): 548 549 """ 550 Define 'node' as the user of attributes, indicating the point where the 551 user is defined. 552 """ 553 554 self.get_namespace()._define_attribute_user(node) 555 556 def use_attribute(self, name, attrname, value=None): 557 558 """ 559 Note usage on the attribute user 'name' of the attribute 'attrname', 560 noting an assignment if 'value' is specified. 561 """ 562 563 return self.get_namespace()._use_attribute(name, attrname, value) 564 565 def use_specific_attribute(self, objname, attrname, from_name=None): 566 567 """ 568 Note usage on the object having the given 'objname' of the attribute 569 'attrname'. If 'objname' is None, the current namespace is chosen as the 570 object providing the attribute. 571 """ 572 573 return self.get_namespace()._use_specific_attribute(objname, attrname, from_name) 574 575 def define_attribute_accessor(self, name, attrname, node, value=None): 576 577 """ 578 Note applicable attribute users providing the given 'name' when 579 accessing the given 'attrname' on the specified 'node', with the 580 optional 'value' indicating an assignment. 581 """ 582 583 self.get_namespace()._define_attribute_accessor(name, attrname, node, value) 584 585 # Visitor methods. 586 587 def default(self, node, *args): 588 raise InspectError("Node class %r is not supported." % node.__class__) 589 590 def NOP(self, node): 591 for n in node.getChildNodes(): 592 self.dispatch(n) 593 594 def NOP_ABANDON(self, node): 595 self.NOP(node) 596 self.abandon_branch() 597 598 def TEST_NOP(self, node): 599 self.use_name("__bool__", node) 600 self.NOP(node) 601 602 def OP(self, node): 603 for n in node.getChildNodes(): 604 self.dispatch(n) 605 return make_instance() 606 607 def TEST_OP(self, node): 608 self.use_name("__bool__", node) 609 self.new_branchpoint() 610 611 # Propagate attribute usage to branches. 612 # Each node starts a new conditional region, effectively making a deeply 613 # nested collection of if-like statements. 614 615 for n in node.nodes: 616 self.new_branch(n) 617 self.dispatch(n) 618 619 # The nested regions must be terminated. 620 621 for n in node.nodes: 622 self.shelve_branch() 623 624 self.merge_branches() 625 return make_instance() 626 627 # Generic support for classes of operations. 628 629 def _ensureOperators(self, node): 630 attr, scope, namespace = self._get_with_scope("$operator") 631 if attr is None: 632 module = node._module 633 module.complete() 634 self["$operator"] = module 635 else: 636 module = attr.get_value() 637 return module 638 639 def _visitOperator(self, node, operator_name=None): 640 641 "Accounting method for the operator 'node'." 642 643 operator_module = self._ensureOperators(node) 644 operator_fn = operator_functions[operator_name or node.__class__.__name__] 645 self.use_specific_attribute(operator_module.full_name(), operator_fn) 646 return self.OP(node) 647 648 def _visitAttr(self, expr, attrname, node): 649 650 """ 651 Process the attribute provided by the given 'expr' with the given 652 'attrname' and involving the given 'node'. 653 """ 654 655 # Attempt to identify the nature of the attribute. 656 657 if isinstance(expr, Attr): 658 value = expr.get_value() 659 660 # Get the attribute and record its usage. 661 # NOTE: Need to provide concrete values for things like base classes 662 # NOTE: while also handling module attribute modification. 663 664 # Only specific class attributes are detected here since class 665 # attribute finalisation has not yet occurred. 666 667 if isinstance(value, (Class, Module)): 668 669 # Check for class.__class__. 670 671 if attrname == "__class__" and isinstance(value, Class): 672 attr = type_class 673 else: 674 attr = value.get(attrname) or make_instance() 675 self.use_specific_attribute(value.full_name(), attrname) 676 677 elif isinstance(value, UnresolvedName): 678 attr = UnresolvedName(attrname, value.full_name(), self) 679 680 # The actual attribute is not readily identifiable and is assumed 681 # to be an instance. 682 683 else: 684 685 # Record any instance attributes. 686 687 if expr.name == "self": 688 self.store_instance_attr(attrname, tentative=True) 689 690 attr = make_instance() 691 692 # Note usage of the attribute where a local is involved. 693 694 self._visitAttrUser(expr, attrname, node) 695 696 # No particular attribute has been identified, thus a general instance 697 # is assumed. 698 699 else: 700 attr = make_instance() 701 self.use_name(attrname, node) 702 703 return attr 704 705 def _visitAttrUser(self, expr, attrname, node, value=None): 706 707 """ 708 Note usage of the attribute provided by 'expr' with the given 'attrname' 709 where a local is involved, annotating the given 'node'. If the optional 710 'value' is given, note an assignment for future effects on attributes 711 where such attributes are inferred from the usage. 712 """ 713 714 # Access to attributes via a local in functions, classes or modules. 715 # Since module-level locals are globals that can be modified 716 # independently of the namespace, any attribute usage observations made 717 # here may be revoked later if such modification is thought to occur. 718 719 if expr.parent is self.get_namespace(): 720 self.define_attribute_accessor(expr.name, attrname, node, value) 721 else: 722 self.use_name(attrname, node.expr, value, ns=expr.parent) 723 724 def _visitConst(self, value): 725 726 """ 727 Register the constant given by 'value', if necessary, returning the 728 resulting object. The type name is noted as being used, thus preserving 729 the class in any generated program. 730 """ 731 732 self.use_specific_attribute("__builtins__", self.importer.get_constant_type_name(value)) 733 const = self.importer.make_constant(value) 734 self.use_constant(const) 735 return const 736 737 def _visitFunction(self, node, name): 738 739 """ 740 Return a function object for the function defined by 'node' with the 741 given 'name'. If a lambda expression is being visited, 'name' should be 742 None. 743 """ 744 745 # Define the function object. 746 747 function = Function( 748 name, 749 self.get_namespace(), 750 node.argnames, 751 node.defaults, 752 (node.flags & 4 != 0), 753 (node.flags & 8 != 0), 754 self.in_loop or self.in_function, 755 self, 756 node 757 ) 758 759 self.add_object(function, any_scope=1) 760 761 # Make a back reference from the node for code generation. 762 763 node.unit = function 764 765 # Process the defaults. 766 767 for n in node.defaults: 768 self.expr = self.dispatch(n) 769 function.store_default(self.expr) 770 771 # Note attribute usage where tuple parameters are involved. 772 773 if function.tuple_parameters(): 774 self.use_name("__getitem__", node) 775 776 # Record the namespace context of the function for later processing. 777 778 self.functions.append((node, self.namespaces + [function])) 779 780 # Store the function. 781 782 if name is not None: 783 self.store(name, function) 784 else: 785 self.store_lambda(function) 786 787 # Test the defaults and assess whether an dynamic object will result. 788 789 function.make_dynamic() 790 return function 791 792 def _visitFunctionBody(self, node, namespaces): 793 794 "Enter the function." 795 796 # Current namespace is the function. 797 # Previous namespace is the class. 798 799 if self.in_class(namespaces): 800 self.in_method = True 801 802 in_function = self.in_function 803 in_loop = self.in_loop 804 self.in_function = True 805 self.in_loop = False 806 807 self.namespaces = namespaces 808 self.dispatch(node.code) 809 810 self.in_loop = in_loop 811 self.in_function = in_function 812 self.in_method = False 813 814 # Specific handler methods. 815 816 visitAdd = _visitOperator 817 818 visitAnd = TEST_OP 819 820 visitAssert = NOP 821 822 def visitAssign(self, node): 823 self.expr = self.dispatch(node.expr) 824 self.in_assignment = True 825 for n in node.nodes: 826 self.dispatch(n) 827 self.in_assignment = False 828 829 def visitAssAttr(self, node): 830 expr = self.dispatch(node.expr) 831 attrname = node.attrname 832 833 # Record the attribute on the presumed target. 834 835 if isinstance(expr, Attr): 836 value = expr.get_value() 837 838 if expr.name == "self": 839 self.store_instance_attr(attrname) 840 self.use_attribute(expr.name, attrname, value) 841 self._visitAttrUser(expr, attrname, node, self.expr) 842 843 # No definite attribute can be identified, since the instance 844 # being accessed may be a subclass of the method's class. 845 846 attr = make_instance() 847 848 elif isinstance(value, Module): 849 self.store_module_attr(attrname, value) 850 attr = value.get(attrname) 851 852 elif isinstance(value, Class): 853 self.store_class_attr(attrname, value) 854 attr = value.get(attrname) 855 856 # Note usage of the attribute where a local is involved. 857 858 else: 859 self._visitAttrUser(expr, attrname, node, self.expr) 860 attr = make_instance() 861 862 else: 863 self.use_name(attrname, node) 864 attr = make_instance() 865 866 node._attr = attr 867 868 def visitAssList(self, node): 869 870 # Declare names which will be used by generated code. 871 872 self.use_name("__getitem__", node) 873 874 # Process the assignment. 875 876 for i, n in enumerate(node.nodes): 877 self.dispatch(n) 878 self._visitConst(i) # for __getitem__(i) at run-time 879 880 def visitAssName(self, node): 881 if node.flags == "OP_DELETE": 882 print >>sys.stderr, "Warning: deletion of attribute %r in %r is not supported." % (node.name, self.full_name()) 883 #raise InspectError("Deletion of attribute %r is not supported." % node.name) 884 self._visitAssName(node) 885 886 def _visitAssName(self, node): 887 self.store(node.name, self.expr) 888 self.define_attribute_user(node) 889 890 # Ensure the presence of the given name in this namespace. 891 # NOTE: Consider not registering assignments involving methods, since 892 # NOTE: this is merely creating aliases for such methods. 893 894 if isinstance(self.get_namespace(), (Class, Module)): 895 if not isinstance(self.expr, Attr) or not isinstance(self.expr.get_value(), Function): 896 self.use_specific_attribute(None, node.name) 897 else: 898 fn = self.expr.get_value() 899 ns = self.get_namespace().full_name() 900 self.use_specific_attribute(fn.parent.full_name(), fn.name, "%s.%s" % (ns, node.name)) 901 902 visitAssTuple = visitAssList 903 904 def visitAugAssign(self, node): 905 906 # Accounting. 907 908 operator_fn = operator_functions.get(node.op) 909 operator_module = self._ensureOperators(node) 910 self.use_specific_attribute(operator_module.full_name(), operator_fn) 911 912 # Process the assignment. 913 914 self.expr = self.dispatch(node.expr) 915 916 # NOTE: Similar to micropython.ast handler code. 917 # NOTE: Slices and subscripts are supported by __setitem__(slice) and 918 # NOTE: not __setslice__. 919 920 if isinstance(node.node, compiler.ast.Name): 921 self._visitAssName(node.node) 922 elif isinstance(node.node, compiler.ast.Getattr): 923 self.visitAssAttr(node.node) 924 else: 925 self.dispatch(node.node) 926 self.use_specific_attribute("__builtins__", "slice") 927 self.use_name("__setitem__", node) 928 929 visitBackquote = OP 930 931 visitBitand = _visitOperator 932 933 visitBitor = _visitOperator 934 935 visitBitxor = _visitOperator 936 937 def visitBreak(self, node): 938 self.NOP(node) 939 self.suspend_broken_branch() 940 941 visitCallFunc = OP 942 943 def visitClass(self, node): 944 945 """ 946 Register the class at the given 'node' subject to the restrictions 947 mentioned in the module docstring. 948 """ 949 950 if self.namespaces: 951 print >>sys.stderr, "Warning: class %r in %r is not global: ignored." % (node.name, self.namespaces[-1].full_name()) 952 return 953 else: 954 if self.in_loop: 955 print >>sys.stderr, "Warning: class %r in %r defined in a loop." % (node.name, self.full_name()) 956 957 cls = get_class(node.name, self.get_namespace(), self, node) 958 959 # Make a back reference from the node for code generation. 960 961 node.unit = cls 962 963 # Process base classes in the context of the class's namespace. 964 # This confines references to such classes to the class instead of 965 # the namespace in which it is defined. 966 967 self.namespaces.append(cls) 968 969 # Visit the base class expressions, attempting to find concrete 970 # definitions of classes. 971 972 for base in node.bases: 973 expr = self.dispatch(base) 974 975 # Each base class must be constant and known at compile-time. 976 977 if isinstance(expr, Attr): 978 if expr.assignments != 1: 979 raise InspectError("Base class %r for %r is not constant: %r" % (base, cls.full_name(), expr)) 980 elif not isinstance(expr.get_value(), Class): 981 raise InspectError("Base class %r for %r is not a class: %r" % (base, cls.full_name(), expr.get_value())) 982 else: 983 cls.add_base(expr.get_value()) 984 985 # Where no expression value is available, the base class is 986 # not identifiable. 987 988 else: 989 raise InspectError("Base class %r for %r is not found: it may be hidden in some way." % (base, cls.full_name())) 990 991 # NOTE: Potentially dubious measure to permit __init__ availability. 992 # If no bases exist, adopt the 'object' class. 993 994 if not node.bases and not (self.name == "__builtins__" and node.name == "object"): 995 expr = self.dispatch(compiler.ast.Name("object")) 996 cls.add_base(expr.get_value()) 997 998 # Make an entry for the class in the parent namespace. 999 1000 self.namespaces.pop() 1001 self.store(node.name, cls) 1002 self.add_object(cls) 1003 1004 # Process the class body in its own namespace. 1005 # Add __name__ to the namespace. 1006 1007 self.namespaces.append(cls) 1008 self.store("__name__", self._visitConst(node.name)) 1009 self.dispatch(node.code) 1010 self.namespaces.pop() 1011 1012 cls.finalise_attribute_usage() 1013 return cls 1014 1015 def visitCompare(self, node): 1016 1017 # Accounting. 1018 # NOTE: Replicates some code in micropython.ast.visitCompare. 1019 1020 self.use_name("__bool__", node) 1021 1022 this_node = node 1023 1024 for op in node.ops: 1025 op_name, next_node = op 1026 1027 # Define name/attribute usage. 1028 # Get the applicable operation. 1029 1030 operator_fn = operator_functions.get(op_name) 1031 1032 # For operators, reference the specific function involved. 1033 1034 if operator_fn is not None: 1035 operator_module = self._ensureOperators(node) 1036 self.use_specific_attribute(operator_module.full_name(), operator_fn) 1037 1038 # Define __contains__ usage on the next node. 1039 1040 elif op_name.endswith("in"): 1041 self.use_name("__contains__", next_node) 1042 1043 this_node = next_node 1044 1045 return self.OP(node) 1046 1047 def visitConst(self, node): 1048 return self._visitConst(node.value) 1049 1050 def visitContinue(self, node): 1051 self.NOP(node) 1052 self.suspend_continuing_branch() 1053 1054 visitDecorators = NOP 1055 1056 visitDict = OP 1057 1058 visitDiscard = NOP 1059 1060 visitDiv = _visitOperator 1061 1062 visitEllipsis = NOP 1063 1064 visitExec = NOP 1065 1066 visitExpression = OP 1067 1068 visitFloorDiv = _visitOperator 1069 1070 def visitFor(self, node): 1071 self.new_branchpoint(node) 1072 1073 # Declare names which will be used by generated code. 1074 1075 self.use_name("__iter__", node.list) 1076 self.use_name("next") 1077 self.use_name("StopIteration") 1078 1079 in_loop = self.in_loop 1080 self.in_loop = True 1081 self.dispatch(node.list) 1082 1083 # NOTE: Could generate AST nodes for the actual operations instead of 1084 # NOTE: manually generating code in micropython.ast. 1085 1086 self.expr = make_instance() # each element is a result of a function call 1087 self.dispatch(node.assign) 1088 1089 # Enter the loop. 1090 # Propagate attribute usage to branches. 1091 1092 self.new_branch(node) 1093 self.dispatch(node.body) 1094 1095 self.resume_continuing_branches() 1096 1097 self.shelve_branch() 1098 1099 self.in_loop = in_loop 1100 1101 # A null branch is used to record a path around the loop. 1102 1103 self.new_branch(node.else_ or NullBranch()) 1104 self.shelve_branch() 1105 1106 self.merge_branches() 1107 1108 # The else clause is evaluated outside any branch. 1109 1110 if node.else_ is not None: 1111 self.dispatch(node.else_) 1112 1113 # Any suspended branches from the loop can now be resumed. 1114 1115 self.resume_broken_branches() 1116 1117 def visitFrom(self, node): 1118 module = self.complete_import(node.modname, True) 1119 1120 for name, alias in node.names: 1121 1122 # For specific names, obtain and store referenced objects using 1123 # the name or any alias provided in the current namespace. 1124 1125 if name != "*": 1126 if module: 1127 1128 # Missing names may refer to submodules. 1129 1130 submodule = self.complete_import(node.modname + "." + name, True) 1131 if submodule: 1132 if not module.has_key(name): 1133 module.store(name, submodule) 1134 1135 # Complete the import if the name was found. 1136 1137 if module.has_key(name): 1138 attr = module[name] 1139 self.store(alias or name, attr) 1140 self.use_specific_attribute(module.full_name(), name) 1141 continue 1142 1143 # Support the import of names from missing modules. 1144 1145 self.store(alias or name, UnresolvedName(name, node.modname, self)) 1146 1147 # For wildcards, obtain and store all objects from a module in the 1148 # current namespace. 1149 1150 else: 1151 if module: 1152 for n in module.keys(): 1153 attr = module[n] 1154 self.store(n, attr) 1155 self.use_specific_attribute(module.full_name(), n) 1156 1157 def visitFunction(self, node): 1158 return self._visitFunction(node, node.name) 1159 1160 visitGenExpr = OP 1161 1162 visitGenExprFor = NOP 1163 1164 visitGenExprIf = NOP 1165 1166 visitGenExprInner = NOP 1167 1168 def visitGetattr(self, node): 1169 node._expr = self.dispatch(node.expr) 1170 node._attr = self._visitAttr(node._expr, node.attrname, node) 1171 return node._attr 1172 1173 def visitGlobal(self, node): 1174 if self.namespaces: 1175 for name in node.names: 1176 ns = self.namespaces[-1] 1177 if not ns.make_global(name): 1178 raise InspectError("Name %r is global and local in %r" % (name, ns.full_name())) 1179 1180 # The name is recorded in an earlier process. 1181 1182 def visitIf(self, node): 1183 self.use_name("__bool__", node) 1184 self.new_branchpoint() 1185 1186 # Propagate attribute usage to branches. 1187 1188 for test, body in node.tests: 1189 self.dispatch(test) 1190 1191 self.new_branch(body) 1192 self.dispatch(body) 1193 self.shelve_branch() 1194 1195 # Maintain a branch for the else clause. 1196 1197 self.new_branch(node.else_ or NullBranch()) 1198 if node.else_ is not None: 1199 self.dispatch(node.else_) 1200 self.shelve_branch() 1201 1202 self.merge_branches() 1203 1204 def visitIfExp(self, node): 1205 self.use_name("__bool__", node) 1206 self.new_branchpoint() 1207 1208 # Propagate attribute usage to branches. 1209 1210 self.dispatch(node.test) 1211 1212 self.new_branch(node.then) 1213 self.dispatch(node.then) 1214 self.shelve_branch() 1215 1216 self.new_branch(node.else_) 1217 self.dispatch(node.else_) 1218 self.shelve_branch() 1219 1220 self.merge_branches() 1221 return make_instance() # either outcome is possible 1222 1223 def visitImport(self, node): 1224 for name, alias in node.names: 1225 module = self.complete_import(name, alias) 1226 if alias is not None: 1227 self.store(alias, module or UnresolvedName(None, name, self)) 1228 else: 1229 name_used = name.split(".")[0] 1230 self.store(name_used, module or UnresolvedName(None, name_used, self)) 1231 1232 visitInvert = _visitOperator 1233 1234 def visitKeyword(self, node): 1235 self.dispatch(node.expr) 1236 self._visitConst(node.name) 1237 self.keyword_names.add(node.name) 1238 1239 def visitLambda(self, node): 1240 fn = self._visitFunction(node, None) 1241 self.use_specific_attribute(None, fn.name) 1242 return fn 1243 1244 visitLeftShift = _visitOperator 1245 1246 def visitList(self, node): 1247 self.use_specific_attribute("__builtins__", "list") 1248 return self.OP(node) 1249 1250 def visitListComp(self, node): 1251 1252 # Note that explicit dispatch is performed. 1253 1254 if node.quals: 1255 self.visitListCompFor(node.quals[0], node.quals[1:], node.expr) 1256 return make_instance() 1257 1258 def visitListCompFor(self, node, following_quals, expr): 1259 self.new_branchpoint() 1260 1261 # Declare names which will be used by generated code. 1262 1263 self.use_name("__iter__", node.list) 1264 self.use_name("next") 1265 1266 in_loop = self.in_loop 1267 self.in_loop = True 1268 self.dispatch(node.list) 1269 1270 # NOTE: Could generate AST nodes for the actual operations instead of 1271 # NOTE: manually generating code in micropython.ast. 1272 1273 self.expr = make_instance() # each element is a result of a function call 1274 self.dispatch(node.assign) 1275 1276 # Enter the loop. 1277 # Propagate attribute usage to branches. 1278 1279 self.new_branch(node) 1280 1281 # Note that explicit dispatch is performed. 1282 1283 if node.ifs: 1284 self.visitListCompIf(node.ifs[0], node.ifs[1:], following_quals, expr) 1285 elif following_quals: 1286 self.visitListCompFor(following_quals[0], following_quals[1:], expr) 1287 else: 1288 self.dispatch(expr) 1289 1290 self.shelve_branch() 1291 self.in_loop = in_loop 1292 1293 self.merge_branches() 1294 1295 def visitListCompIf(self, node, following_ifs, following_quals, expr): 1296 self.use_name("__bool__", node) 1297 self.new_branchpoint() 1298 1299 # Propagate attribute usage to branches. 1300 1301 self.dispatch(node.test) 1302 1303 # Note that explicit dispatch is performed. 1304 1305 if following_ifs: 1306 self.visitListCompIf(following_ifs[0], following_ifs[1:], following_quals, expr) 1307 elif following_quals: 1308 self.visitListCompFor(following_quals[0], following_quals[1:], expr) 1309 else: 1310 self.new_branch(expr) 1311 self.dispatch(expr) 1312 self.shelve_branch() 1313 1314 # Maintain a branch for the else clause. 1315 1316 self.new_branch(NullBranch()) 1317 self.shelve_branch() 1318 1319 self.merge_branches() 1320 1321 visitMod = _visitOperator 1322 1323 def visitModule(self, node): 1324 1325 # Make a back reference from the node for code generation. 1326 1327 node.unit = self 1328 return self.dispatch(node.node) 1329 1330 visitMul = _visitOperator 1331 1332 def visitName(self, node): 1333 attr = self.get_namespace().get_using_node(node.name, node) or make_instance() 1334 node._attr = attr 1335 return attr 1336 1337 def visitNot(self, node): 1338 self.use_name("__bool__", node) 1339 self.dispatch(node.expr) 1340 return make_instance() 1341 1342 visitOr = TEST_OP 1343 1344 visitPass = NOP 1345 1346 visitPower = _visitOperator 1347 1348 def _visitPrint(self, node, function_name): 1349 self.NOP(node) 1350 self.use_specific_attribute("__builtins__", function_name) 1351 1352 def visitPrint(self, node): 1353 self._visitPrint(node, "_print") 1354 1355 def visitPrintnl(self, node): 1356 self._visitPrint(node, "_printnl") 1357 1358 visitRaise = NOP_ABANDON 1359 1360 visitReturn = NOP_ABANDON 1361 1362 visitRightShift = _visitOperator 1363 1364 def visitSlice(self, node): 1365 return self._visitOperator(node, self.in_assignment and "AssSlice" or "Slice") 1366 1367 visitSliceobj = OP 1368 1369 def visitStmt(self, node): 1370 for n in node.nodes: 1371 self.dispatch(n) 1372 1373 visitSub = _visitOperator 1374 1375 def visitSubscript(self, node): 1376 return self._visitOperator(node, self.in_assignment and "AssSubscript" or "Subscript") 1377 1378 def visitTryExcept(self, node): 1379 self.new_branchpoint() 1380 self.dispatch(node.body) 1381 1382 for name, var, n in node.handlers: 1383 if name is not None: 1384 self.dispatch(name) 1385 1386 self.new_branch(n) 1387 1388 # Any abandoned branches from the body can now be resumed. 1389 1390 self.resume_abandoned_branches() 1391 1392 # Establish the local for the handler. 1393 1394 if var is not None: 1395 self.dispatch(var) 1396 if n is not None: 1397 self.dispatch(n) 1398 1399 self.shelve_branch() 1400 1401 # The else clause maintains the usage from the body but without the 1402 # abandoned branches since they would never lead to the else clause 1403 # being executed. 1404 1405 self.new_branch(node.else_ or NullBranch()) 1406 if node.else_ is not None: 1407 self.dispatch(node.else_) 1408 self.shelve_branch() 1409 1410 self.merge_branches() 1411 1412 visitTryFinally = NOP 1413 1414 visitTuple = OP 1415 1416 visitUnaryAdd = _visitOperator 1417 1418 visitUnarySub = _visitOperator 1419 1420 def visitWhile(self, node): 1421 self.use_name("__bool__", node) 1422 self.new_branchpoint(node) 1423 1424 # Propagate attribute usage to branches. 1425 1426 in_loop = self.in_loop 1427 self.in_loop = True 1428 1429 # The test is evaluated initially and again in the loop. 1430 1431 self.dispatch(node.test) 1432 1433 self.new_branch(node) 1434 self.dispatch(node.body) 1435 1436 self.resume_continuing_branches() 1437 1438 self.dispatch(node.test) 1439 self.shelve_branch() 1440 1441 self.in_loop = in_loop 1442 1443 # A null branch is used to record a path around the loop. 1444 1445 self.new_branch(node.else_ or NullBranch()) 1446 self.shelve_branch() 1447 1448 self.merge_branches() 1449 1450 # The else clause is evaluated outside any branch. 1451 1452 if node.else_ is not None: 1453 self.dispatch(node.else_) 1454 1455 # Any suspended branches from the loop can now be resumed. 1456 1457 self.resume_broken_branches() 1458 1459 visitWith = NOP 1460 1461 visitYield = NOP 1462 1463 # vim: tabstop=4 expandtab shiftwidth=4