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, 2013, 2014 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, get_module_name 76 from micropython.data import * 77 from micropython.errors import * 78 from micropython.stdcompiler import compiler 79 import sys 80 81 class NullBranch(compiler.ast.AttributeUser): 82 83 "A class representing an attribute user for a non-existent branch." 84 85 pass 86 87 # Program visitors. 88 89 class InspectedModule(ASTVisitor, Module): 90 91 """ 92 An inspected module, providing core details via the Module superclass, but 93 capable of being used as an AST visitor. 94 95 A module can be inspected through the invocation of the following methods in 96 order: 97 98 1. parse 99 2. process 100 3. vacuum 101 4. finalise 102 103 A module importer can be expected to perform these invocations. 104 """ 105 106 def __init__(self, name, importer): 107 108 """ 109 Initialise this visitor with a module 'name' and an 'importer' which is 110 used to provide access to other modules when required. 111 """ 112 113 Module.__init__(self, name, importer) 114 self.visitor = self 115 self.filename = None 116 117 # Import machinery links. 118 119 self.builtins = self.importer.modules.get("__builtins__") 120 self.loaded = False 121 self.completed = False 122 123 # Current expression state. 124 125 self.expr = None 126 self.in_assignment = False # For slice and subscript handling. 127 128 # Namespace state. 129 130 self.in_method = False # Find instance attributes in all methods. 131 self.in_function = False # Note function presence, affecting definitions. 132 self.in_loop = False # Note loop "membership", affecting assignments. 133 self.namespaces = [] 134 self.functions = [] 135 136 def parse(self, filename): 137 138 "Parse the file having the given 'filename'." 139 140 self.filename = filename 141 self.astnode = module = compiler.parseFile(filename) 142 143 # Detect and record imports and globals declared in the module. 144 145 self.process_structure(module) 146 147 def complete(self): 148 if not self.completed: 149 self.completed = True 150 self.process() 151 if self.importer.verbose: 152 print >>sys.stderr, "Completed import of", self.full_name() 153 154 def process(self): 155 return self.process_module(self.astnode) 156 157 def process_module(self, module): 158 159 """ 160 Process the given 'module', visiting module-level code and function 161 code. 162 """ 163 164 # Add __name__ to the namespace. 165 166 self.store("__name__", self._visitConst(self.full_name())) 167 168 # Visit module-level code, also recording global names. 169 170 processed = self.dispatch(module) 171 172 self.finalise_attribute_usage() 173 174 # Visit functions. 175 176 self.process_functions() 177 178 # Add references to other modules declared using the __all__ global. 179 180 if self.has_key("__all__"): 181 all = self["__all__"] 182 if isinstance(all, compiler.ast.List): 183 for n in all.nodes: 184 self.store(n.value, self.importer.add_module(self.name + "." + n.value)) 185 186 return processed 187 188 def process_functions(self): 189 190 """ 191 Process all function bodies. Deferred imports may occur during this 192 process. 193 """ 194 195 # Then, visit each function, recording other names. This happens to 196 # work for lambda definitions inside functions since they are added to 197 # the end of self.functions and are thus visited as the iteration 198 # reaches the end of the original list. 199 200 for node in self.functions: 201 self._visitFunctionBody(node) 202 node.unit.finalise_attribute_usage() 203 204 def process_structure(self, node): 205 206 """ 207 Within the given 'node', process global declarations, adjusting the 208 module namespace, and import statements, building a module dependency 209 hierarchy. 210 """ 211 212 for n in node.getChildNodes(): 213 214 # Module global detection. 215 216 if isinstance(n, compiler.ast.Global): 217 for name in n.names: 218 219 # Each name may potentially be assigned many times. 220 # We don't try and find out the specifics at this point and 221 # just indicate that the name cannot be relied upon for 222 # various observations. 223 224 self.modify_name(name) 225 226 # Module import declarations. 227 228 elif isinstance(n, compiler.ast.From): 229 modname, names = get_module_name(n, self) 230 231 # Perform whole module relative imports. 232 233 if not modname: 234 for name, alias in names: 235 self.record_import(name, n) 236 237 # Otherwise, perform normal "from" imports. 238 239 else: 240 # Load the mentioned module. 241 242 self.record_import(modname, n) 243 244 # Speculatively load modules for names beneath the module. 245 246 for name, alias in n.names: 247 subname = modname + "." + name 248 self.record_import(subname, n) 249 250 elif isinstance(n, compiler.ast.Import): 251 252 # Load the mentioned module. 253 254 for name, alias in n.names: 255 self.record_import(name, n) 256 257 # Nodes using operator module functions. 258 259 elif operator_functions.has_key(n.__class__.__name__) or \ 260 isinstance(n, (compiler.ast.AugAssign, compiler.ast.Compare)): 261 262 n._module = self.importer.load("operator") 263 264 else: 265 self.process_structure(n) 266 267 def get_module_paths(self, name): 268 269 """ 270 Return the paths of modules leading to the module having the given 271 'name'. 272 """ 273 274 names = [] 275 parts = [] 276 for part in name.split("."): 277 parts.append(part) 278 names.append(".".join(parts)) 279 return names 280 281 def record_import(self, name, node): 282 283 """ 284 Record an import of a module with the given 'name' occurring at the 285 given 'node'. 286 """ 287 288 module = self.importer.load(name, 1, importer=node) 289 if module and not module.loaded: 290 self.importer.circular_imports.add(module) 291 292 def complete_import(self, name, return_leaf): 293 294 """ 295 Complete the import of the module with the given 'name', returning the 296 module itself if 'return_leaf' is a true value, or returning the root of 297 the module hierarchy if 'return_leaf' is a false value. 298 """ 299 300 top = module = None 301 302 for modname in self.get_module_paths(name): 303 304 # Attempt to get the module, returning None for non-existent 305 # modules. 306 307 try: 308 module = self.importer.get_module(modname) 309 except KeyError: 310 return None 311 312 if module: 313 module.complete() 314 315 if top is None: 316 top = module 317 318 if return_leaf: 319 return module 320 else: 321 return top 322 323 def vacuum(self): 324 325 """ 326 Vacuum the module namespace, removing unreferenced objects and unused 327 names. 328 """ 329 330 self.vacuum_object(self) 331 332 all_objects = list(self.all_objects) 333 334 for obj in all_objects: 335 self.vacuum_object(obj) 336 337 def vacuum_object(self, obj, delete_all=0): 338 339 "Vacuum the given object 'obj'." 340 341 # Get all constant objects in apparent use. 342 343 if delete_all: 344 obj_objects = set() 345 else: 346 obj_objects = [] 347 for name, attr in obj.items_for_vacuum(): 348 349 # Get constant objects for attributes in use. 350 351 if self.importer.uses_attribute(obj.full_name(), name) and \ 352 attr is not None and attr.is_constant(): 353 354 value = attr.get_value() 355 obj_objects.append(value) 356 357 # Now vacuum unused attributes and objects not in use. 358 359 for name, attr in obj.items_for_vacuum(): 360 361 # Only consider deleting entire unused objects or things accessible 362 # via names which are never used. 363 364 if delete_all or not self.importer.uses_attribute(obj.full_name(), name): 365 obj.vacuum_item(name) 366 367 # Delete any unambiguous attribute value. Such values can only 368 # have been defined within the object and therefore are not 369 # redefined by other code regions. 370 371 if attr is not None and attr.is_constant(): 372 value = attr.get_value() 373 374 # The value must have this object as a parent. 375 # However, it must not be shared by several names. 376 377 if value is not obj and value.parent is obj and \ 378 value in self.all_objects and value not in obj_objects: 379 380 self.all_objects.remove(value) 381 382 # Delete class contents and lambdas from functions. 383 384 self.vacuum_object(value, 1) 385 386 def unfinalise(self): 387 388 "Reset finalised information for the module." 389 390 for obj in self.all_objects: 391 obj.unfinalise_attributes() 392 393 def finalise(self, objtable): 394 395 "Finalise the module." 396 397 for obj in self.all_objects: 398 obj.finalise(objtable) 399 400 self.finalise_users(objtable) 401 402 def add_object(self, obj, any_scope=0): 403 404 """ 405 Record 'obj' if non-local or if the optional 'any_scope' is set to a 406 true value. 407 """ 408 409 if any_scope or not (self.namespaces and isinstance(self.namespaces[-1], Function)): 410 self.all_objects.add(obj) 411 412 # Namespace methods. 413 414 def in_class(self, namespaces=None): 415 namespaces = namespaces or self.namespaces 416 return len(namespaces) > 1 and isinstance(namespaces[-2], Class) 417 418 def store(self, name, obj, static_def=False): 419 420 """ 421 Record attribute or local 'name', storing 'obj'. Where 'static_def' is 422 specified and set to a true value, the namespace will record a static 423 definition for the given name. 424 """ 425 426 # Store in the module. 427 428 if not self.namespaces: 429 if self.in_loop and self.used_in_scope(name, "builtins"): 430 raise InspectError("Name %r already used as a built-in." % name) 431 else: 432 ns = self 433 434 # Or store locally. 435 436 else: 437 locals = self.namespaces[-1] 438 439 if self.in_loop and locals.used_in_scope(name, "global") and not name in locals.globals: 440 raise InspectError("Name %r already used as global." % name) 441 elif self.in_loop and locals.used_in_scope(name, "builtins"): 442 raise InspectError("Name %r already used as a built-in." % name) 443 else: 444 ns = locals 445 446 ns.set(name, obj, not self.in_loop) 447 if static_def: 448 ns.get(name).static_assignments += 1 449 return ns.get(name) 450 451 def store_lambda(self, obj): 452 453 "Store a lambda function 'obj'." 454 455 self.add_object(obj) 456 self.get_namespace().add_lambda(obj) 457 458 def store_module_attr(self, name, module): 459 460 """ 461 Record module attribute 'name' in the given 'module' using the current 462 expression. 463 """ 464 465 module.set(name, self.expr, 0) 466 self.use_specific_attribute(module.full_name(), name) 467 468 def store_class_attr(self, name, cls): 469 470 """ 471 Record class attribute 'name' in the given class 'cls' using the current 472 expression. 473 """ 474 475 cls.set(name, self.expr, 0) 476 self.use_specific_attribute(cls.full_name(), name) 477 478 def store_instance_attr(self, name, tentative=False): 479 480 """ 481 Record instance attribute 'name' in the current class. If 'tentative' is 482 set to a true value, the instance attribute will be discarded if a class 483 attribute is observed. 484 """ 485 486 if self.in_method: 487 488 # Current namespace is the function. 489 # Previous namespace is the class. 490 491 cls = self.namespaces[-2] 492 cls.add_instance_attribute(name, tentative) 493 494 # NOTE: The instance attribute, although defined in a specific 495 # NOTE: class, obviously appears in all descendant classes. 496 497 self.use_specific_attribute(cls.full_name(), name) 498 499 def get_namespace(self): 500 501 "Return the parent (or most recent) namespace currently exposed." 502 503 return (self.namespaces[-1:] or [self])[0] 504 505 get_unit = get_namespace # compatibility method for error handling 506 507 def use_name(self, name, node=None, value=None, ns=None): 508 509 """ 510 Use the given 'name' within the current namespace/unit, either in 511 conjunction with a particular object (if 'node' is specified and not 512 None) or unconditionally. 513 """ 514 515 unit = self.get_namespace() 516 517 # Handle attribute usage situations within the current unit. 518 519 if node is not None and isinstance(node, compiler.ast.Name) and ns is unit: 520 self.use_attribute(node.name, name, value) 521 522 # For general name usage, declare usage of the given name from this 523 # particular unit. 524 525 else: 526 self.importer.use_name(name, unit.full_name(), value) 527 528 def use_constant(self, const): 529 530 "Use the given 'const' within the current namespace/unit." 531 532 unit = self.get_namespace() 533 self.importer.use_constant(const, unit.full_name()) 534 535 # Attribute usage methods. 536 # These are convenience methods which refer to the specific namespace's 537 # implementation of these operations. 538 539 def new_branchpoint(self, loop_node=None): 540 self.get_namespace()._new_branchpoint(loop_node) 541 542 def new_branch(self, node): 543 self.get_namespace()._new_branch(node) 544 545 def abandon_branch(self): 546 self.get_namespace()._abandon_branch() 547 548 def suspend_broken_branch(self): 549 self.get_namespace()._suspend_broken_branch() 550 551 def suspend_continuing_branch(self): 552 self.get_namespace()._suspend_continuing_branch() 553 554 def shelve_branch(self): 555 self.get_namespace()._shelve_branch() 556 557 def merge_branches(self): 558 self.get_namespace()._merge_branches() 559 560 def resume_broken_branches(self): 561 self.get_namespace()._resume_broken_branches() 562 563 def resume_continuing_branches(self): 564 self.get_namespace()._resume_continuing_branches() 565 566 def resume_abandoned_branches(self): 567 self.get_namespace()._resume_abandoned_branches() 568 569 def define_attribute_user(self, node): 570 571 """ 572 Define 'node' as the user of attributes, indicating the point where the 573 user is defined. 574 """ 575 576 self.get_namespace()._define_attribute_user(node) 577 578 def use_attribute(self, name, attrname, value=None): 579 580 """ 581 Note usage on the attribute user 'name' of the attribute 'attrname', 582 noting an assignment if 'value' is specified. 583 """ 584 585 return self.get_namespace()._use_attribute(name, attrname, value) 586 587 def use_specific_attribute(self, objname, attrname, from_name=None): 588 589 """ 590 Note usage on the object having the given 'objname' of the attribute 591 'attrname'. If 'objname' is None, the current namespace is chosen as the 592 object providing the attribute. 593 """ 594 595 return self.get_namespace()._use_specific_attribute(objname, attrname, from_name) 596 597 def define_attribute_accessor(self, name, attrname, node, value=None): 598 599 """ 600 Note applicable attribute users providing the given 'name' when 601 accessing the given 'attrname' on the specified 'node', with the 602 optional 'value' indicating an assignment. 603 """ 604 605 self.get_namespace()._define_attribute_accessor(name, attrname, node, value) 606 607 # Visitor methods. 608 609 def default(self, node, *args): 610 raise InspectError("Node class %r is not supported." % node.__class__) 611 612 def NOP(self, node): 613 for n in node.getChildNodes(): 614 self.dispatch(n) 615 616 def NOP_ABANDON(self, node): 617 self.NOP(node) 618 self.abandon_branch() 619 620 def TEST_NOP(self, node): 621 self.use_name("__bool__", node) 622 self.NOP(node) 623 624 def OP(self, node): 625 for n in node.getChildNodes(): 626 self.dispatch(n) 627 return make_instance() 628 629 def TEST_OP(self, node): 630 self.use_name("__bool__", node) 631 self.new_branchpoint() 632 633 # Propagate attribute usage to branches. 634 # Each node starts a new conditional region, effectively making a deeply 635 # nested collection of if-like statements. 636 637 for n in node.nodes: 638 self.new_branch(n) 639 self.dispatch(n) 640 641 # The nested regions must be terminated. 642 643 for n in node.nodes: 644 self.shelve_branch() 645 646 self.merge_branches() 647 return make_instance() 648 649 # Generic support for classes of operations. 650 651 def _ensureOperators(self, node): 652 attr, scope, namespace = self._get_with_scope("$operator") 653 if attr is None: 654 module = node._module 655 module.complete() 656 self["$operator"] = module 657 else: 658 module = attr.get_value() 659 return module 660 661 def _visitOperator(self, node, operator_name=None): 662 663 "Accounting method for the operator 'node'." 664 665 operator_module = self._ensureOperators(node) 666 operator_fn = operator_functions[operator_name or node.__class__.__name__] 667 self.use_specific_attribute(operator_module.full_name(), operator_fn) 668 node._attr = node._module.get(operator_fn) or make_instance() 669 return self.OP(node) 670 671 def _visitAttr(self, expr, attrname, node): 672 673 """ 674 Process the attribute provided by the given 'expr' with the given 675 'attrname' and involving the given 'node'. 676 """ 677 678 # Attempt to identify the nature of the attribute. 679 680 if isinstance(expr, BaseAttr): 681 if isinstance(expr, LocalAttr): 682 value = expr.attr.get_value() 683 else: 684 value = expr.get_value() 685 686 # Get the attribute and record its usage. 687 # NOTE: Need to provide concrete values for things like base classes 688 # NOTE: while also handling module attribute modification. 689 690 # Only specific class attributes are detected here since class 691 # attribute finalisation has not yet occurred. 692 693 if isinstance(value, (Class, Module)): 694 695 # Check for class.__class__. 696 697 if attrname == "__class__" and isinstance(value, Class): 698 attr = get_constant_class("type") 699 else: 700 attr = value.get(attrname) or make_instance() 701 self.use_specific_attribute(value.full_name(), attrname) 702 703 elif isinstance(value, UnresolvedName): 704 attr = UnresolvedName(attrname, value.full_name(), self) 705 706 # The actual attribute is not readily identifiable and is assumed 707 # to be an instance. 708 709 else: 710 711 # Record any instance attributes. 712 713 if expr.name == "self": 714 self.store_instance_attr(attrname, tentative=True) 715 716 attr = make_instance() 717 718 # Note usage of the attribute where a local is involved. 719 720 self._visitAttrUser(expr, attrname, node) 721 722 # Constants provide specific kinds of expressions. 723 # NOTE: If attributes are accessed on a pre-made, but not yet defined 724 # NOTE: class, no useful attribute will be available. 725 726 elif isinstance(expr, Const): 727 attr = get_constant_class(expr.get_class_name()).all_attributes().get(attrname) or make_instance() 728 729 # No particular attribute has been identified, thus a general instance 730 # is assumed. 731 732 else: 733 attr = make_instance() 734 self.use_name(attrname, node) 735 736 return attr 737 738 def _visitAttrUser(self, expr, attrname, node, value=None): 739 740 """ 741 Note usage of the attribute provided by 'expr' with the given 'attrname' 742 where a local is involved, annotating the given 'node'. If the optional 743 'value' is given, note an assignment for future effects on attributes 744 where such attributes are inferred from the usage. 745 """ 746 747 # Access to attributes via a local in functions, classes or modules. 748 # Since module-level locals are globals that can be modified 749 # independently of the namespace, any attribute usage observations made 750 # here may be revoked later if such modification is thought to occur. 751 752 if expr.parent is self.get_namespace(): 753 self.define_attribute_accessor(expr.name, attrname, node, value) 754 else: 755 self.use_name(attrname, node.expr, value, ns=expr.parent) 756 757 def _visitConst(self, value): 758 759 """ 760 Register the constant given by 'value', if necessary, returning the 761 resulting object. The type name is noted as being used, thus preserving 762 the class in any generated program. 763 """ 764 765 self.use_specific_attribute("__builtins__", self.importer.get_constant_type_name(value)) 766 const = self.importer.make_constant(value) 767 self.use_constant(const) 768 return const 769 770 def _visitFunction(self, node, name): 771 772 """ 773 Return a function object for the function defined by 'node' with the 774 given 'name'. If a lambda expression is being visited, 'name' should be 775 None. 776 """ 777 778 # Define the function object. 779 780 function = get_function( 781 name, 782 self.get_namespace(), 783 node.argnames, 784 node.defaults, 785 (node.flags & 4 != 0), 786 (node.flags & 8 != 0), 787 self.in_loop or self.in_function, 788 self, 789 node 790 ) 791 792 self.add_object(function, any_scope=1) 793 794 # Make a back reference from the node for code generation. 795 796 node.unit = function 797 798 # Process the defaults. 799 800 for n in node.defaults: 801 self.expr = self.dispatch(n) 802 function.store_default(self.expr) 803 804 # Note attribute usage where tuple parameters are involved. 805 806 if function.tuple_parameters(): 807 self.use_name("__getitem__", node) 808 809 # Record the namespace context of the function for later processing. 810 811 function.set_parent_namespaces(self.namespaces[:]) 812 self.functions.append(node) 813 814 # Store the function. 815 816 if name is not None: 817 self.define_attribute_user(compiler.ast.AssName(name, "OP_ASSIGN")) 818 self.store(name, function, static_def=True) 819 else: 820 self.store_lambda(function) 821 822 # Test the defaults and assess whether an dynamic object will result. 823 824 function.make_dynamic() 825 return function 826 827 def _visitFunctionBody(self, node): 828 829 "Enter the function." 830 831 function = node.unit 832 namespaces = function.get_parent_namespaces() + [function] 833 834 # Current namespace is the function. 835 # Previous namespace is the class. 836 837 if self.in_class(namespaces): 838 self.in_method = True 839 840 in_function = self.in_function 841 in_loop = self.in_loop 842 self.in_function = True 843 self.in_loop = False 844 845 self.namespaces = namespaces 846 self.dispatch(node.code) 847 848 self.in_loop = in_loop 849 self.in_function = in_function 850 self.in_method = False 851 852 # Specific handler methods. 853 854 visitAdd = _visitOperator 855 856 visitAnd = TEST_OP 857 858 visitAssert = NOP 859 860 def visitAssign(self, node): 861 self.expr = self.dispatch(node.expr) 862 self.in_assignment = True 863 for n in node.nodes: 864 self.dispatch(n) 865 self.in_assignment = False 866 867 def visitAssAttr(self, node): 868 expr = self.dispatch(node.expr) 869 attrname = node.attrname 870 871 # Record the attribute on the presumed target. 872 873 if isinstance(expr, BaseAttr): 874 if isinstance(expr, LocalAttr): 875 value = expr.attr.get_value() 876 else: 877 value = expr.get_value() 878 879 if expr.name == "self": 880 self.store_instance_attr(attrname) 881 self.use_attribute(expr.name, attrname, value) 882 self._visitAttrUser(expr, attrname, node, self.expr) 883 884 # No definite attribute can be identified, since the instance 885 # being accessed may be a subclass of the method's class. 886 887 attr = make_instance() 888 889 elif isinstance(value, Module): 890 self.store_module_attr(attrname, value) 891 attr = value.get(attrname) 892 893 elif isinstance(value, Class): 894 self.store_class_attr(attrname, value) 895 attr = value.get(attrname) 896 897 # Note usage of the attribute where a local is involved. 898 899 else: 900 self._visitAttrUser(expr, attrname, node, self.expr) 901 attr = make_instance() 902 903 else: 904 self.use_name(attrname, node) 905 attr = make_instance() 906 907 node._expr = expr 908 node._attr = attr 909 910 def visitAssList(self, node): 911 912 # Declare names which will be used by generated code. 913 914 self.use_name("__getitem__", node) 915 916 # Process the assignment. 917 918 expr = self.expr 919 self.expr = make_instance() # each element is a result of an item access 920 921 for i, n in enumerate(node.nodes): 922 self.dispatch(n) 923 self._visitConst(i) # for __getitem__(i) at run-time 924 925 self.expr = expr 926 927 def visitAssName(self, node): 928 if node.flags == "OP_DELETE": 929 print >>sys.stderr, "Warning: deletion of attribute %r in %r is not supported." % (node.name, self.full_name()) 930 #raise InspectError("Deletion of attribute %r is not supported." % node.name) 931 self._visitAssName(node) 932 933 def _visitAssName(self, node): 934 self.define_attribute_user(node) 935 self.store(node.name, self.expr) 936 937 # Ensure the presence of the given name in this namespace. 938 # NOTE: Consider not registering assignments involving methods, since 939 # NOTE: this is merely creating aliases for such methods. 940 941 if isinstance(self.get_namespace(), (Class, Module)): 942 if isinstance(self.expr, BaseAttr): 943 if isinstance(self.expr, LocalAttr): 944 value = self.expr.attr.get_value() 945 else: 946 value = self.expr.get_value() 947 else: 948 value = None 949 if not value or not isinstance(value, Function): 950 self.use_specific_attribute(None, node.name) 951 else: 952 fn = value 953 ns = self.get_namespace().full_name() 954 self.use_specific_attribute(fn.parent.full_name(), fn.name, "%s.%s" % (ns, node.name)) 955 956 visitAssTuple = visitAssList 957 958 def visitAugAssign(self, node): 959 960 # Accounting. 961 962 operator_fn = operator_functions.get(node.op) 963 operator_module = self._ensureOperators(node) 964 self.use_specific_attribute(operator_module.full_name(), operator_fn) 965 966 # Process the assignment. 967 968 self.expr = self.dispatch(node.expr) 969 self.dispatch(node.node) 970 971 # NOTE: Slices and subscripts are supported by __setitem__(slice) and 972 # NOTE: not __setslice__. 973 974 if isinstance(node.node, compiler.ast.Name): 975 self._visitAssName(node.node) 976 elif isinstance(node.node, compiler.ast.Getattr): 977 self.visitAssAttr(node.node) 978 else: 979 self.use_specific_attribute("__builtins__", "slice") 980 self.use_name("__setitem__", node) 981 982 visitBackquote = OP 983 984 visitBitand = _visitOperator 985 986 visitBitor = _visitOperator 987 988 visitBitxor = _visitOperator 989 990 def visitBreak(self, node): 991 self.NOP(node) 992 self.suspend_broken_branch() 993 994 visitCallFunc = OP 995 996 def visitClass(self, node): 997 998 """ 999 Register the class at the given 'node' subject to the restrictions 1000 mentioned in the module docstring. 1001 """ 1002 1003 if self.namespaces: 1004 print >>sys.stderr, "Warning: class %r in %r is not global: ignored." % (node.name, self.namespaces[-1].full_name()) 1005 return 1006 else: 1007 if self.in_loop: 1008 print >>sys.stderr, "Warning: class %r in %r defined in a loop." % (node.name, self.full_name()) 1009 1010 cls = get_class(node.name, self.get_namespace(), self, node) 1011 1012 # Make a back reference from the node for code generation. 1013 1014 node.unit = cls 1015 1016 # Process base classes in the context of the class's namespace. 1017 # This confines references to such classes to the class instead of 1018 # the namespace in which it is defined. 1019 1020 self.namespaces.append(cls) 1021 1022 # Visit the base class expressions, attempting to find concrete 1023 # definitions of classes. 1024 1025 for base in node.bases: 1026 expr = self.dispatch(base) 1027 1028 # Each base class must be constant and known at compile-time. 1029 1030 if isinstance(expr, BaseAttr): 1031 if isinstance(expr, LocalAttr): 1032 value = expr.attr.get_value() 1033 else: 1034 value = expr.get_value() 1035 1036 if not value: 1037 raise InspectError("Base class %r for %r is not constant: %r" % (base, cls.full_name(), expr)) 1038 elif not isinstance(value, Class): 1039 raise InspectError("Base class %r for %r is not a class: %r" % (base, cls.full_name(), value)) 1040 else: 1041 cls.add_base(value) 1042 1043 # Where no expression value is available, the base class is 1044 # not identifiable. 1045 1046 else: 1047 raise InspectError("Base class %r for %r is not found: it may be hidden in some way." % (base, cls.full_name())) 1048 1049 # NOTE: Potentially dubious measure to permit __init__ availability. 1050 # If no bases exist, adopt the 'object' class. 1051 1052 if not node.bases and not (self.name == "__builtins__" and node.name == "object"): 1053 expr = self.dispatch(compiler.ast.Name("object")) 1054 cls.add_base(expr.get_value()) 1055 1056 # Make an entry for the class in the parent namespace. 1057 1058 self.namespaces.pop() 1059 self.define_attribute_user(compiler.ast.AssName(node.name, "OP_ASSIGN")) 1060 self.store(node.name, cls, static_def=True) 1061 self.add_object(cls) 1062 1063 # Process the class body in its own namespace. 1064 # Add __name__ to the namespace. 1065 1066 self.namespaces.append(cls) 1067 self.store("__name__", self._visitConst(node.name)) 1068 self.dispatch(node.code) 1069 self.namespaces.pop() 1070 1071 cls.finalise_attribute_usage() 1072 return cls 1073 1074 def visitCompare(self, node): 1075 1076 # Accounting. 1077 # NOTE: Replicates some code in micropython.ast.visitCompare. 1078 1079 self.use_name("__bool__", node) 1080 1081 this_node = node 1082 1083 for op in node.ops: 1084 op_name, next_node = op 1085 1086 # Define name/attribute usage. 1087 # Get the applicable operation. 1088 1089 operator_fn = operator_functions.get(op_name) 1090 1091 # For operators, reference the specific function involved. 1092 1093 if operator_fn is not None: 1094 operator_module = self._ensureOperators(node) 1095 self.use_specific_attribute(operator_module.full_name(), operator_fn) 1096 1097 # Define __contains__ usage on the next node. 1098 1099 elif op_name.endswith("in"): 1100 self.use_name("__contains__", next_node) 1101 1102 this_node = next_node 1103 1104 return self.OP(node) 1105 1106 def visitConst(self, node): 1107 return self._visitConst(node.value) 1108 1109 def visitContinue(self, node): 1110 self.NOP(node) 1111 self.suspend_continuing_branch() 1112 1113 visitDecorators = NOP 1114 1115 def visitDict(self, node): 1116 self.use_specific_attribute("__builtins__", "dict") 1117 return self.OP(node) 1118 1119 visitDiscard = NOP 1120 1121 visitDiv = _visitOperator 1122 1123 visitEllipsis = NOP 1124 1125 visitExec = NOP 1126 1127 visitExpression = OP 1128 1129 visitFloorDiv = _visitOperator 1130 1131 def visitFor(self, node): 1132 self.new_branchpoint(node) 1133 1134 # Declare names which will be used by generated code. 1135 1136 self.use_name("__iter__", node.list) 1137 self.use_name("next") 1138 self.use_name("StopIteration") 1139 1140 in_loop = self.in_loop 1141 self.in_loop = True 1142 self.dispatch(node.list) 1143 1144 # NOTE: Could generate AST nodes for the actual operations instead of 1145 # NOTE: manually generating code in micropython.ast. 1146 1147 self.expr = make_instance() # each element is a result of a function call 1148 self.dispatch(node.assign) 1149 1150 # Enter the loop. 1151 # Propagate attribute usage to branches. 1152 1153 self.new_branch(node) 1154 self.dispatch(node.body) 1155 1156 self.resume_continuing_branches() 1157 1158 self.shelve_branch() 1159 1160 self.in_loop = in_loop 1161 1162 # A null branch is used to record a path around the loop. 1163 1164 self.new_branch(node.else_ or NullBranch()) 1165 self.shelve_branch() 1166 1167 self.merge_branches() 1168 1169 # The else clause is evaluated outside any branch. 1170 1171 if node.else_ is not None: 1172 self.dispatch(node.else_) 1173 1174 # Any suspended branches from the loop can now be resumed. 1175 1176 self.resume_broken_branches() 1177 1178 def visitFrom(self, node): 1179 modname, names = get_module_name(node, self) 1180 1181 if not modname: 1182 return self._visitImport(names) 1183 1184 module = self.complete_import(modname, True) 1185 1186 for name, alias in node.names: 1187 1188 # For specific names, obtain and store referenced objects using 1189 # the name or any alias provided in the current namespace. 1190 1191 if name != "*": 1192 if module: 1193 1194 # Missing names may refer to submodules. 1195 1196 submodule = self.complete_import(modname + "." + name, True) 1197 if submodule: 1198 if not module.has_key(name): 1199 module.store(name, submodule) 1200 1201 # Complete the import if the name was found. 1202 1203 if module.has_key(name): 1204 attr = module[name] 1205 self.store(alias or name, attr) 1206 self.use_specific_attribute(module.full_name(), name) 1207 continue 1208 1209 # Support the import of names from missing modules. 1210 1211 self.store(alias or name, UnresolvedName(name, modname, self)) 1212 1213 # For wildcards, obtain and store all objects from a module in the 1214 # current namespace. 1215 1216 else: 1217 if module: 1218 for n in module.keys(): 1219 attr = module[n] 1220 self.store(n, attr) 1221 self.use_specific_attribute(module.full_name(), n) 1222 1223 def visitFunction(self, node): 1224 return self._visitFunction(node, node.name) 1225 1226 # NOTE: GenExpr support is very similar to ListComp support. 1227 1228 def visitGenExpr(self, node): 1229 self.dispatch(node.code) 1230 1231 def visitGenExprInner(self, node): 1232 1233 # Note that explicit dispatch is performed. 1234 1235 if node.quals: 1236 self.visitGenExprFor(node.quals[0], node.quals[1:], node.expr) 1237 return make_instance() 1238 1239 def visitGenExprFor(self, node, following_quals, expr): 1240 self.new_branchpoint() 1241 1242 # Declare names which will be used by generated code. 1243 1244 self.use_name("__iter__", node.iter) 1245 self.use_name("next") 1246 1247 in_loop = self.in_loop 1248 self.in_loop = True 1249 self.dispatch(node.iter) 1250 1251 # NOTE: Could generate AST nodes for the actual operations instead of 1252 # NOTE: manually generating code in micropython.ast. 1253 1254 self.expr = make_instance() # each element is a result of a function call 1255 self.dispatch(node.assign) 1256 1257 # Enter the loop. 1258 # Propagate attribute usage to branches. 1259 1260 self.new_branch(node) 1261 1262 # Note that explicit dispatch is performed. 1263 1264 if node.ifs: 1265 self.visitGenExprIf(node.ifs[0], node.ifs[1:], following_quals, expr) 1266 elif following_quals: 1267 self.visitGenExprFor(following_quals[0], following_quals[1:], expr) 1268 else: 1269 self.dispatch(expr) 1270 1271 self.shelve_branch() 1272 self.in_loop = in_loop 1273 1274 self.merge_branches() 1275 1276 def visitGenExprIf(self, node, following_ifs, following_quals, expr): 1277 self.use_name("__bool__", node) 1278 self.new_branchpoint() 1279 1280 # Propagate attribute usage to branches. 1281 1282 self.dispatch(node.test) 1283 1284 # Note that explicit dispatch is performed. 1285 1286 if following_ifs: 1287 self.visitGenExprIf(following_ifs[0], following_ifs[1:], following_quals, expr) 1288 elif following_quals: 1289 self.visitGenExprFor(following_quals[0], following_quals[1:], expr) 1290 else: 1291 self.new_branch(expr) 1292 self.dispatch(expr) 1293 self.shelve_branch() 1294 1295 # Maintain a branch for the else clause. 1296 1297 self.new_branch(NullBranch()) 1298 self.shelve_branch() 1299 1300 self.merge_branches() 1301 1302 def visitGetattr(self, node): 1303 node._expr = self.dispatch(node.expr) 1304 node._attr = self._visitAttr(node._expr, node.attrname, node) 1305 return node._attr 1306 1307 def visitGlobal(self, node): 1308 if self.namespaces: 1309 for name in node.names: 1310 ns = self.namespaces[-1] 1311 if not ns.make_global(name): 1312 raise InspectError("Name %r is global and local in %r" % (name, ns.full_name())) 1313 1314 # The name is recorded in an earlier process. 1315 1316 def visitIf(self, node): 1317 self.use_name("__bool__", node) 1318 self.new_branchpoint() 1319 1320 # Propagate attribute usage to branches. 1321 1322 for test, body in node.tests: 1323 self.dispatch(test) 1324 1325 self.new_branch(body) 1326 self.dispatch(body) 1327 self.shelve_branch() 1328 1329 # Maintain a branch for the else clause. 1330 1331 self.new_branch(node.else_ or NullBranch()) 1332 if node.else_ is not None: 1333 self.dispatch(node.else_) 1334 self.shelve_branch() 1335 1336 self.merge_branches() 1337 1338 def visitIfExp(self, node): 1339 self.use_name("__bool__", node) 1340 self.new_branchpoint() 1341 1342 # Propagate attribute usage to branches. 1343 1344 self.dispatch(node.test) 1345 1346 self.new_branch(node.then) 1347 self.dispatch(node.then) 1348 self.shelve_branch() 1349 1350 self.new_branch(node.else_) 1351 self.dispatch(node.else_) 1352 self.shelve_branch() 1353 1354 self.merge_branches() 1355 return make_instance() # either outcome is possible 1356 1357 def visitImport(self, node): 1358 self._visitImport(node.names) 1359 1360 def _visitImport(self, names): 1361 for name, alias in names: 1362 module = self.complete_import(name, alias) 1363 if alias is not None: 1364 self.store(alias, module or UnresolvedName(None, name, self)) 1365 else: 1366 name_used = name.split(".")[0] 1367 self.store(name_used, module or UnresolvedName(None, name_used, self)) 1368 1369 visitInvert = _visitOperator 1370 1371 def visitKeyword(self, node): 1372 self.dispatch(node.expr) 1373 self._visitConst(node.name) 1374 self.keyword_names.add(node.name) 1375 1376 def visitLambda(self, node): 1377 fn = self._visitFunction(node, None) 1378 self.use_specific_attribute(None, fn.name) 1379 return fn 1380 1381 visitLeftShift = _visitOperator 1382 1383 def visitList(self, node): 1384 self.use_specific_attribute("__builtins__", "list") 1385 return self.OP(node) 1386 1387 def visitListComp(self, node): 1388 1389 # Note that explicit dispatch is performed. 1390 1391 if node.quals: 1392 self.visitListCompFor(node.quals[0], node.quals[1:], node.expr) 1393 return make_instance() 1394 1395 def visitListCompFor(self, node, following_quals, expr): 1396 self.new_branchpoint() 1397 1398 # Declare names which will be used by generated code. 1399 1400 self.use_name("__iter__", node.list) 1401 self.use_name("next") 1402 1403 in_loop = self.in_loop 1404 self.in_loop = True 1405 self.dispatch(node.list) 1406 1407 # NOTE: Could generate AST nodes for the actual operations instead of 1408 # NOTE: manually generating code in micropython.ast. 1409 1410 self.expr = make_instance() # each element is a result of a function call 1411 self.dispatch(node.assign) 1412 1413 # Enter the loop. 1414 # Propagate attribute usage to branches. 1415 1416 self.new_branch(node) 1417 1418 # Note that explicit dispatch is performed. 1419 1420 if node.ifs: 1421 self.visitListCompIf(node.ifs[0], node.ifs[1:], following_quals, expr) 1422 elif following_quals: 1423 self.visitListCompFor(following_quals[0], following_quals[1:], expr) 1424 else: 1425 self.dispatch(expr) 1426 1427 self.shelve_branch() 1428 self.in_loop = in_loop 1429 1430 self.merge_branches() 1431 1432 def visitListCompIf(self, node, following_ifs, following_quals, expr): 1433 self.use_name("__bool__", node) 1434 self.new_branchpoint() 1435 1436 # Propagate attribute usage to branches. 1437 1438 self.dispatch(node.test) 1439 1440 # Note that explicit dispatch is performed. 1441 1442 if following_ifs: 1443 self.visitListCompIf(following_ifs[0], following_ifs[1:], following_quals, expr) 1444 elif following_quals: 1445 self.visitListCompFor(following_quals[0], following_quals[1:], expr) 1446 else: 1447 self.new_branch(expr) 1448 self.dispatch(expr) 1449 self.shelve_branch() 1450 1451 # Maintain a branch for the else clause. 1452 1453 self.new_branch(NullBranch()) 1454 self.shelve_branch() 1455 1456 self.merge_branches() 1457 1458 visitMod = _visitOperator 1459 1460 def visitModule(self, node): 1461 1462 # Make a back reference from the node for code generation. 1463 1464 node.unit = self 1465 return self.dispatch(node.node) 1466 1467 visitMul = _visitOperator 1468 1469 def visitName(self, node): 1470 attr = self.get_namespace().get_using_node(node.name, node) or make_instance() 1471 node._attr = self.get_namespace().get_for_local(node.name) or attr 1472 return node._attr 1473 1474 def visitNot(self, node): 1475 self.use_name("__bool__", node) 1476 self.dispatch(node.expr) 1477 return make_instance() 1478 1479 visitOr = TEST_OP 1480 1481 visitPass = NOP 1482 1483 visitPower = _visitOperator 1484 1485 def _visitPrint(self, node, function_name): 1486 self.NOP(node) 1487 self.use_specific_attribute("__builtins__", function_name) 1488 1489 def visitPrint(self, node): 1490 self._visitPrint(node, "_print") 1491 1492 def visitPrintnl(self, node): 1493 self._visitPrint(node, "_printnl") 1494 1495 visitRaise = NOP_ABANDON 1496 1497 visitReturn = NOP_ABANDON 1498 1499 visitRightShift = _visitOperator 1500 1501 def visitSet(self, node): 1502 self.use_specific_attribute("__builtins__", "set") 1503 return self.OP(node) 1504 1505 def visitSlice(self, node): 1506 return self._visitOperator(node, self.in_assignment and "AssSlice" or "Slice") 1507 1508 visitSliceobj = OP 1509 1510 def visitStmt(self, node): 1511 for n in node.nodes: 1512 self.dispatch(n) 1513 1514 visitSub = _visitOperator 1515 1516 def visitSubscript(self, node): 1517 return self._visitOperator(node, self.in_assignment and "AssSubscript" or "Subscript") 1518 1519 def visitTryExcept(self, node): 1520 self.new_branchpoint() 1521 self.dispatch(node.body) 1522 1523 for name, var, n in node.handlers: 1524 if name is not None: 1525 self.dispatch(name) 1526 1527 self.new_branch(n) 1528 1529 # Any abandoned branches from the body can now be resumed. 1530 1531 self.resume_abandoned_branches() 1532 1533 # Establish the local for the handler. 1534 1535 if var is not None: 1536 self.dispatch(var) 1537 if n is not None: 1538 self.dispatch(n) 1539 1540 self.shelve_branch() 1541 1542 # The else clause maintains the usage from the body but without the 1543 # abandoned branches since they would never lead to the else clause 1544 # being executed. 1545 1546 self.new_branch(node.else_ or NullBranch()) 1547 if node.else_ is not None: 1548 self.dispatch(node.else_) 1549 self.shelve_branch() 1550 1551 self.merge_branches() 1552 1553 visitTryFinally = NOP 1554 1555 visitTuple = OP 1556 1557 visitUnaryAdd = _visitOperator 1558 1559 visitUnarySub = _visitOperator 1560 1561 def visitWhile(self, node): 1562 self.use_name("__bool__", node) 1563 self.new_branchpoint(node) 1564 1565 # Propagate attribute usage to branches. 1566 1567 in_loop = self.in_loop 1568 self.in_loop = True 1569 1570 # The test is evaluated initially and again in the loop. 1571 1572 self.dispatch(node.test) 1573 1574 self.new_branch(node) 1575 self.dispatch(node.body) 1576 1577 self.resume_continuing_branches() 1578 1579 self.dispatch(node.test) 1580 self.shelve_branch() 1581 1582 self.in_loop = in_loop 1583 1584 # A null branch is used to record a path around the loop. 1585 1586 self.new_branch(node.else_ or NullBranch()) 1587 self.shelve_branch() 1588 1589 self.merge_branches() 1590 1591 # The else clause is evaluated outside any branch. 1592 1593 if node.else_ is not None: 1594 self.dispatch(node.else_) 1595 1596 # Any suspended branches from the loop can now be resumed. 1597 1598 self.resume_broken_branches() 1599 1600 visitWith = NOP 1601 1602 visitYield = NOP 1603 1604 # vim: tabstop=4 expandtab shiftwidth=4