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 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 import compiler.ast 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, namespaces in self.functions: 201 self._visitFunctionBody(node, namespaces) 202 namespaces[-1].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 return self.OP(node) 669 670 def _visitAttr(self, expr, attrname, node): 671 672 """ 673 Process the attribute provided by the given 'expr' with the given 674 'attrname' and involving the given 'node'. 675 """ 676 677 # Attempt to identify the nature of the attribute. 678 679 if isinstance(expr, Attr): 680 value = expr.get_value() 681 682 # Get the attribute and record its usage. 683 # NOTE: Need to provide concrete values for things like base classes 684 # NOTE: while also handling module attribute modification. 685 686 # Only specific class attributes are detected here since class 687 # attribute finalisation has not yet occurred. 688 689 if isinstance(value, (Class, Module)): 690 691 # Check for class.__class__. 692 693 if attrname == "__class__" and isinstance(value, Class): 694 attr = get_constant_class("type") 695 else: 696 attr = value.get(attrname) or make_instance() 697 self.use_specific_attribute(value.full_name(), attrname) 698 699 elif isinstance(value, UnresolvedName): 700 attr = UnresolvedName(attrname, value.full_name(), self) 701 702 # The actual attribute is not readily identifiable and is assumed 703 # to be an instance. 704 705 else: 706 707 # Record any instance attributes. 708 709 if expr.name == "self": 710 self.store_instance_attr(attrname, tentative=True) 711 712 attr = make_instance() 713 714 # Note usage of the attribute where a local is involved. 715 716 self._visitAttrUser(expr, attrname, node) 717 718 # Constants provide specific kinds of expressions. 719 # NOTE: If attributes are accessed on a pre-made, but not yet defined 720 # NOTE: class, no useful attribute will be available. 721 722 elif isinstance(expr, Const): 723 attr = get_constant_class(expr.get_class_name()).all_attributes().get(attrname) or make_instance() 724 725 # No particular attribute has been identified, thus a general instance 726 # is assumed. 727 728 else: 729 attr = make_instance() 730 self.use_name(attrname, node) 731 732 return attr 733 734 def _visitAttrUser(self, expr, attrname, node, value=None): 735 736 """ 737 Note usage of the attribute provided by 'expr' with the given 'attrname' 738 where a local is involved, annotating the given 'node'. If the optional 739 'value' is given, note an assignment for future effects on attributes 740 where such attributes are inferred from the usage. 741 """ 742 743 # Access to attributes via a local in functions, classes or modules. 744 # Since module-level locals are globals that can be modified 745 # independently of the namespace, any attribute usage observations made 746 # here may be revoked later if such modification is thought to occur. 747 748 if expr.parent is self.get_namespace(): 749 self.define_attribute_accessor(expr.name, attrname, node, value) 750 else: 751 self.use_name(attrname, node.expr, value, ns=expr.parent) 752 753 def _visitConst(self, value): 754 755 """ 756 Register the constant given by 'value', if necessary, returning the 757 resulting object. The type name is noted as being used, thus preserving 758 the class in any generated program. 759 """ 760 761 self.use_specific_attribute("__builtins__", self.importer.get_constant_type_name(value)) 762 const = self.importer.make_constant(value) 763 self.use_constant(const) 764 return const 765 766 def _visitFunction(self, node, name): 767 768 """ 769 Return a function object for the function defined by 'node' with the 770 given 'name'. If a lambda expression is being visited, 'name' should be 771 None. 772 """ 773 774 # Define the function object. 775 776 function = get_function( 777 name, 778 self.get_namespace(), 779 node.argnames, 780 node.defaults, 781 (node.flags & 4 != 0), 782 (node.flags & 8 != 0), 783 self.in_loop or self.in_function, 784 self, 785 node 786 ) 787 788 self.add_object(function, any_scope=1) 789 790 # Make a back reference from the node for code generation. 791 792 node.unit = function 793 794 # Process the defaults. 795 796 for n in node.defaults: 797 self.expr = self.dispatch(n) 798 function.store_default(self.expr) 799 800 # Note attribute usage where tuple parameters are involved. 801 802 if function.tuple_parameters(): 803 self.use_name("__getitem__", node) 804 805 # Record the namespace context of the function for later processing. 806 807 self.functions.append((node, self.namespaces + [function])) 808 809 # Store the function. 810 811 if name is not None: 812 self.store(name, function, static_def=True) 813 else: 814 self.store_lambda(function) 815 816 # Test the defaults and assess whether an dynamic object will result. 817 818 function.make_dynamic() 819 return function 820 821 def _visitFunctionBody(self, node, namespaces): 822 823 "Enter the function." 824 825 # Current namespace is the function. 826 # Previous namespace is the class. 827 828 if self.in_class(namespaces): 829 self.in_method = True 830 831 in_function = self.in_function 832 in_loop = self.in_loop 833 self.in_function = True 834 self.in_loop = False 835 836 self.namespaces = namespaces 837 self.dispatch(node.code) 838 839 self.in_loop = in_loop 840 self.in_function = in_function 841 self.in_method = False 842 843 # Specific handler methods. 844 845 visitAdd = _visitOperator 846 847 visitAnd = TEST_OP 848 849 visitAssert = NOP 850 851 def visitAssign(self, node): 852 self.expr = self.dispatch(node.expr) 853 self.in_assignment = True 854 for n in node.nodes: 855 self.dispatch(n) 856 self.in_assignment = False 857 858 def visitAssAttr(self, node): 859 expr = self.dispatch(node.expr) 860 attrname = node.attrname 861 862 # Record the attribute on the presumed target. 863 864 if isinstance(expr, Attr): 865 value = expr.get_value() 866 867 if expr.name == "self": 868 self.store_instance_attr(attrname) 869 self.use_attribute(expr.name, attrname, value) 870 self._visitAttrUser(expr, attrname, node, self.expr) 871 872 # No definite attribute can be identified, since the instance 873 # being accessed may be a subclass of the method's class. 874 875 attr = make_instance() 876 877 elif isinstance(value, Module): 878 self.store_module_attr(attrname, value) 879 attr = value.get(attrname) 880 881 elif isinstance(value, Class): 882 self.store_class_attr(attrname, value) 883 attr = value.get(attrname) 884 885 # Note usage of the attribute where a local is involved. 886 887 else: 888 self._visitAttrUser(expr, attrname, node, self.expr) 889 attr = make_instance() 890 891 else: 892 self.use_name(attrname, node) 893 attr = make_instance() 894 895 node._expr = expr 896 node._attr = attr 897 898 def visitAssList(self, node): 899 900 # Declare names which will be used by generated code. 901 902 self.use_name("__getitem__", node) 903 904 # Process the assignment. 905 906 expr = self.expr 907 self.expr = make_instance() # each element is a result of an item access 908 909 for i, n in enumerate(node.nodes): 910 self.dispatch(n) 911 self._visitConst(i) # for __getitem__(i) at run-time 912 913 self.expr = expr 914 915 def visitAssName(self, node): 916 if node.flags == "OP_DELETE": 917 print >>sys.stderr, "Warning: deletion of attribute %r in %r is not supported." % (node.name, self.full_name()) 918 #raise InspectError("Deletion of attribute %r is not supported." % node.name) 919 self._visitAssName(node) 920 921 def _visitAssName(self, node): 922 self.define_attribute_user(node) 923 self.store(node.name, self.expr) 924 925 # Ensure the presence of the given name in this namespace. 926 # NOTE: Consider not registering assignments involving methods, since 927 # NOTE: this is merely creating aliases for such methods. 928 929 if isinstance(self.get_namespace(), (Class, Module)): 930 if not isinstance(self.expr, Attr) or not isinstance(self.expr.get_value(), Function): 931 self.use_specific_attribute(None, node.name) 932 else: 933 fn = self.expr.get_value() 934 ns = self.get_namespace().full_name() 935 self.use_specific_attribute(fn.parent.full_name(), fn.name, "%s.%s" % (ns, node.name)) 936 937 visitAssTuple = visitAssList 938 939 def visitAugAssign(self, node): 940 941 # Accounting. 942 943 operator_fn = operator_functions.get(node.op) 944 operator_module = self._ensureOperators(node) 945 self.use_specific_attribute(operator_module.full_name(), operator_fn) 946 947 # Process the assignment. 948 949 self.expr = self.dispatch(node.expr) 950 951 # NOTE: Similar to micropython.ast handler code. 952 # NOTE: Slices and subscripts are supported by __setitem__(slice) and 953 # NOTE: not __setslice__. 954 955 if isinstance(node.node, compiler.ast.Name): 956 self._visitAssName(node.node) 957 elif isinstance(node.node, compiler.ast.Getattr): 958 self.visitAssAttr(node.node) 959 else: 960 self.dispatch(node.node) 961 self.use_specific_attribute("__builtins__", "slice") 962 self.use_name("__setitem__", node) 963 964 visitBackquote = OP 965 966 visitBitand = _visitOperator 967 968 visitBitor = _visitOperator 969 970 visitBitxor = _visitOperator 971 972 def visitBreak(self, node): 973 self.NOP(node) 974 self.suspend_broken_branch() 975 976 visitCallFunc = OP 977 978 def visitClass(self, node): 979 980 """ 981 Register the class at the given 'node' subject to the restrictions 982 mentioned in the module docstring. 983 """ 984 985 if self.namespaces: 986 print >>sys.stderr, "Warning: class %r in %r is not global: ignored." % (node.name, self.namespaces[-1].full_name()) 987 return 988 else: 989 if self.in_loop: 990 print >>sys.stderr, "Warning: class %r in %r defined in a loop." % (node.name, self.full_name()) 991 992 cls = get_class(node.name, self.get_namespace(), self, node) 993 994 # Make a back reference from the node for code generation. 995 996 node.unit = cls 997 998 # Process base classes in the context of the class's namespace. 999 # This confines references to such classes to the class instead of 1000 # the namespace in which it is defined. 1001 1002 self.namespaces.append(cls) 1003 1004 # Visit the base class expressions, attempting to find concrete 1005 # definitions of classes. 1006 1007 for base in node.bases: 1008 expr = self.dispatch(base) 1009 1010 # Each base class must be constant and known at compile-time. 1011 1012 if isinstance(expr, Attr): 1013 if expr.assignments != 1: 1014 raise InspectError("Base class %r for %r is not constant: %r" % (base, cls.full_name(), expr)) 1015 elif not isinstance(expr.get_value(), Class): 1016 raise InspectError("Base class %r for %r is not a class: %r" % (base, cls.full_name(), expr.get_value())) 1017 else: 1018 cls.add_base(expr.get_value()) 1019 1020 # Where no expression value is available, the base class is 1021 # not identifiable. 1022 1023 else: 1024 raise InspectError("Base class %r for %r is not found: it may be hidden in some way." % (base, cls.full_name())) 1025 1026 # NOTE: Potentially dubious measure to permit __init__ availability. 1027 # If no bases exist, adopt the 'object' class. 1028 1029 if not node.bases and not (self.name == "__builtins__" and node.name == "object"): 1030 expr = self.dispatch(compiler.ast.Name("object")) 1031 cls.add_base(expr.get_value()) 1032 1033 # Make an entry for the class in the parent namespace. 1034 1035 self.namespaces.pop() 1036 self.store(node.name, cls, static_def=True) 1037 self.define_attribute_user(node) 1038 self.add_object(cls) 1039 1040 # Process the class body in its own namespace. 1041 # Add __name__ to the namespace. 1042 1043 self.namespaces.append(cls) 1044 self.store("__name__", self._visitConst(node.name)) 1045 self.dispatch(node.code) 1046 self.namespaces.pop() 1047 1048 cls.finalise_attribute_usage() 1049 return cls 1050 1051 def visitCompare(self, node): 1052 1053 # Accounting. 1054 # NOTE: Replicates some code in micropython.ast.visitCompare. 1055 1056 self.use_name("__bool__", node) 1057 1058 this_node = node 1059 1060 for op in node.ops: 1061 op_name, next_node = op 1062 1063 # Define name/attribute usage. 1064 # Get the applicable operation. 1065 1066 operator_fn = operator_functions.get(op_name) 1067 1068 # For operators, reference the specific function involved. 1069 1070 if operator_fn is not None: 1071 operator_module = self._ensureOperators(node) 1072 self.use_specific_attribute(operator_module.full_name(), operator_fn) 1073 1074 # Define __contains__ usage on the next node. 1075 1076 elif op_name.endswith("in"): 1077 self.use_name("__contains__", next_node) 1078 1079 this_node = next_node 1080 1081 return self.OP(node) 1082 1083 def visitConst(self, node): 1084 return self._visitConst(node.value) 1085 1086 def visitContinue(self, node): 1087 self.NOP(node) 1088 self.suspend_continuing_branch() 1089 1090 visitDecorators = NOP 1091 1092 def visitDict(self, node): 1093 self.use_specific_attribute("__builtins__", "dict") 1094 return self.OP(node) 1095 1096 visitDiscard = NOP 1097 1098 visitDiv = _visitOperator 1099 1100 visitEllipsis = NOP 1101 1102 visitExec = NOP 1103 1104 visitExpression = OP 1105 1106 visitFloorDiv = _visitOperator 1107 1108 def visitFor(self, node): 1109 self.new_branchpoint(node) 1110 1111 # Declare names which will be used by generated code. 1112 1113 self.use_name("__iter__", node.list) 1114 self.use_name("next") 1115 self.use_name("StopIteration") 1116 1117 in_loop = self.in_loop 1118 self.in_loop = True 1119 self.dispatch(node.list) 1120 1121 # NOTE: Could generate AST nodes for the actual operations instead of 1122 # NOTE: manually generating code in micropython.ast. 1123 1124 self.expr = make_instance() # each element is a result of a function call 1125 self.dispatch(node.assign) 1126 1127 # Enter the loop. 1128 # Propagate attribute usage to branches. 1129 1130 self.new_branch(node) 1131 self.dispatch(node.body) 1132 1133 self.resume_continuing_branches() 1134 1135 self.shelve_branch() 1136 1137 self.in_loop = in_loop 1138 1139 # A null branch is used to record a path around the loop. 1140 1141 self.new_branch(node.else_ or NullBranch()) 1142 self.shelve_branch() 1143 1144 self.merge_branches() 1145 1146 # The else clause is evaluated outside any branch. 1147 1148 if node.else_ is not None: 1149 self.dispatch(node.else_) 1150 1151 # Any suspended branches from the loop can now be resumed. 1152 1153 self.resume_broken_branches() 1154 1155 def visitFrom(self, node): 1156 modname, names = get_module_name(node, self) 1157 1158 if not modname: 1159 return self._visitImport(names) 1160 1161 module = self.complete_import(modname, True) 1162 1163 for name, alias in node.names: 1164 1165 # For specific names, obtain and store referenced objects using 1166 # the name or any alias provided in the current namespace. 1167 1168 if name != "*": 1169 if module: 1170 1171 # Missing names may refer to submodules. 1172 1173 submodule = self.complete_import(modname + "." + name, True) 1174 if submodule: 1175 if not module.has_key(name): 1176 module.store(name, submodule) 1177 1178 # Complete the import if the name was found. 1179 1180 if module.has_key(name): 1181 attr = module[name] 1182 self.store(alias or name, attr) 1183 self.use_specific_attribute(module.full_name(), name) 1184 continue 1185 1186 # Support the import of names from missing modules. 1187 1188 self.store(alias or name, UnresolvedName(name, modname, self)) 1189 1190 # For wildcards, obtain and store all objects from a module in the 1191 # current namespace. 1192 1193 else: 1194 if module: 1195 for n in module.keys(): 1196 attr = module[n] 1197 self.store(n, attr) 1198 self.use_specific_attribute(module.full_name(), n) 1199 1200 def visitFunction(self, node): 1201 return self._visitFunction(node, node.name) 1202 1203 visitGenExpr = OP 1204 1205 visitGenExprFor = NOP 1206 1207 visitGenExprIf = NOP 1208 1209 visitGenExprInner = NOP 1210 1211 def visitGetattr(self, node): 1212 node._expr = self.dispatch(node.expr) 1213 node._attr = self._visitAttr(node._expr, node.attrname, node) 1214 return node._attr 1215 1216 def visitGlobal(self, node): 1217 if self.namespaces: 1218 for name in node.names: 1219 ns = self.namespaces[-1] 1220 if not ns.make_global(name): 1221 raise InspectError("Name %r is global and local in %r" % (name, ns.full_name())) 1222 1223 # The name is recorded in an earlier process. 1224 1225 def visitIf(self, node): 1226 self.use_name("__bool__", node) 1227 self.new_branchpoint() 1228 1229 # Propagate attribute usage to branches. 1230 1231 for test, body in node.tests: 1232 self.dispatch(test) 1233 1234 self.new_branch(body) 1235 self.dispatch(body) 1236 self.shelve_branch() 1237 1238 # Maintain a branch for the else clause. 1239 1240 self.new_branch(node.else_ or NullBranch()) 1241 if node.else_ is not None: 1242 self.dispatch(node.else_) 1243 self.shelve_branch() 1244 1245 self.merge_branches() 1246 1247 def visitIfExp(self, node): 1248 self.use_name("__bool__", node) 1249 self.new_branchpoint() 1250 1251 # Propagate attribute usage to branches. 1252 1253 self.dispatch(node.test) 1254 1255 self.new_branch(node.then) 1256 self.dispatch(node.then) 1257 self.shelve_branch() 1258 1259 self.new_branch(node.else_) 1260 self.dispatch(node.else_) 1261 self.shelve_branch() 1262 1263 self.merge_branches() 1264 return make_instance() # either outcome is possible 1265 1266 def visitImport(self, node): 1267 self._visitImport(node.names) 1268 1269 def _visitImport(self, names): 1270 for name, alias in names: 1271 module = self.complete_import(name, alias) 1272 if alias is not None: 1273 self.store(alias, module or UnresolvedName(None, name, self)) 1274 else: 1275 name_used = name.split(".")[0] 1276 self.store(name_used, module or UnresolvedName(None, name_used, self)) 1277 1278 visitInvert = _visitOperator 1279 1280 def visitKeyword(self, node): 1281 self.dispatch(node.expr) 1282 self._visitConst(node.name) 1283 self.keyword_names.add(node.name) 1284 1285 def visitLambda(self, node): 1286 fn = self._visitFunction(node, None) 1287 self.use_specific_attribute(None, fn.name) 1288 return fn 1289 1290 visitLeftShift = _visitOperator 1291 1292 def visitList(self, node): 1293 self.use_specific_attribute("__builtins__", "list") 1294 return self.OP(node) 1295 1296 def visitListComp(self, node): 1297 1298 # Note that explicit dispatch is performed. 1299 1300 if node.quals: 1301 self.visitListCompFor(node.quals[0], node.quals[1:], node.expr) 1302 return make_instance() 1303 1304 def visitListCompFor(self, node, following_quals, expr): 1305 self.new_branchpoint() 1306 1307 # Declare names which will be used by generated code. 1308 1309 self.use_name("__iter__", node.list) 1310 self.use_name("next") 1311 1312 in_loop = self.in_loop 1313 self.in_loop = True 1314 self.dispatch(node.list) 1315 1316 # NOTE: Could generate AST nodes for the actual operations instead of 1317 # NOTE: manually generating code in micropython.ast. 1318 1319 self.expr = make_instance() # each element is a result of a function call 1320 self.dispatch(node.assign) 1321 1322 # Enter the loop. 1323 # Propagate attribute usage to branches. 1324 1325 self.new_branch(node) 1326 1327 # Note that explicit dispatch is performed. 1328 1329 if node.ifs: 1330 self.visitListCompIf(node.ifs[0], node.ifs[1:], following_quals, expr) 1331 elif following_quals: 1332 self.visitListCompFor(following_quals[0], following_quals[1:], expr) 1333 else: 1334 self.dispatch(expr) 1335 1336 self.shelve_branch() 1337 self.in_loop = in_loop 1338 1339 self.merge_branches() 1340 1341 def visitListCompIf(self, node, following_ifs, following_quals, expr): 1342 self.use_name("__bool__", node) 1343 self.new_branchpoint() 1344 1345 # Propagate attribute usage to branches. 1346 1347 self.dispatch(node.test) 1348 1349 # Note that explicit dispatch is performed. 1350 1351 if following_ifs: 1352 self.visitListCompIf(following_ifs[0], following_ifs[1:], following_quals, expr) 1353 elif following_quals: 1354 self.visitListCompFor(following_quals[0], following_quals[1:], expr) 1355 else: 1356 self.new_branch(expr) 1357 self.dispatch(expr) 1358 self.shelve_branch() 1359 1360 # Maintain a branch for the else clause. 1361 1362 self.new_branch(NullBranch()) 1363 self.shelve_branch() 1364 1365 self.merge_branches() 1366 1367 visitMod = _visitOperator 1368 1369 def visitModule(self, node): 1370 1371 # Make a back reference from the node for code generation. 1372 1373 node.unit = self 1374 return self.dispatch(node.node) 1375 1376 visitMul = _visitOperator 1377 1378 def visitName(self, node): 1379 attr = self.get_namespace().get_using_node(node.name, node) or make_instance() 1380 node._attr = attr 1381 return attr 1382 1383 def visitNot(self, node): 1384 self.use_name("__bool__", node) 1385 self.dispatch(node.expr) 1386 return make_instance() 1387 1388 visitOr = TEST_OP 1389 1390 visitPass = NOP 1391 1392 visitPower = _visitOperator 1393 1394 def _visitPrint(self, node, function_name): 1395 self.NOP(node) 1396 self.use_specific_attribute("__builtins__", function_name) 1397 1398 def visitPrint(self, node): 1399 self._visitPrint(node, "_print") 1400 1401 def visitPrintnl(self, node): 1402 self._visitPrint(node, "_printnl") 1403 1404 visitRaise = NOP_ABANDON 1405 1406 visitReturn = NOP_ABANDON 1407 1408 visitRightShift = _visitOperator 1409 1410 def visitSet(self, node): 1411 self.use_specific_attribute("__builtins__", "set") 1412 return self.OP(node) 1413 1414 def visitSlice(self, node): 1415 return self._visitOperator(node, self.in_assignment and "AssSlice" or "Slice") 1416 1417 visitSliceobj = OP 1418 1419 def visitStmt(self, node): 1420 for n in node.nodes: 1421 self.dispatch(n) 1422 1423 visitSub = _visitOperator 1424 1425 def visitSubscript(self, node): 1426 return self._visitOperator(node, self.in_assignment and "AssSubscript" or "Subscript") 1427 1428 def visitTryExcept(self, node): 1429 self.new_branchpoint() 1430 self.dispatch(node.body) 1431 1432 for name, var, n in node.handlers: 1433 if name is not None: 1434 self.dispatch(name) 1435 1436 self.new_branch(n) 1437 1438 # Any abandoned branches from the body can now be resumed. 1439 1440 self.resume_abandoned_branches() 1441 1442 # Establish the local for the handler. 1443 1444 if var is not None: 1445 self.dispatch(var) 1446 if n is not None: 1447 self.dispatch(n) 1448 1449 self.shelve_branch() 1450 1451 # The else clause maintains the usage from the body but without the 1452 # abandoned branches since they would never lead to the else clause 1453 # being executed. 1454 1455 self.new_branch(node.else_ or NullBranch()) 1456 if node.else_ is not None: 1457 self.dispatch(node.else_) 1458 self.shelve_branch() 1459 1460 self.merge_branches() 1461 1462 visitTryFinally = NOP 1463 1464 visitTuple = OP 1465 1466 visitUnaryAdd = _visitOperator 1467 1468 visitUnarySub = _visitOperator 1469 1470 def visitWhile(self, node): 1471 self.use_name("__bool__", node) 1472 self.new_branchpoint(node) 1473 1474 # Propagate attribute usage to branches. 1475 1476 in_loop = self.in_loop 1477 self.in_loop = True 1478 1479 # The test is evaluated initially and again in the loop. 1480 1481 self.dispatch(node.test) 1482 1483 self.new_branch(node) 1484 self.dispatch(node.body) 1485 1486 self.resume_continuing_branches() 1487 1488 self.dispatch(node.test) 1489 self.shelve_branch() 1490 1491 self.in_loop = in_loop 1492 1493 # A null branch is used to record a path around the loop. 1494 1495 self.new_branch(node.else_ or NullBranch()) 1496 self.shelve_branch() 1497 1498 self.merge_branches() 1499 1500 # The else clause is evaluated outside any branch. 1501 1502 if node.else_ is not None: 1503 self.dispatch(node.else_) 1504 1505 # Any suspended branches from the loop can now be resumed. 1506 1507 self.resume_broken_branches() 1508 1509 visitWith = NOP 1510 1511 visitYield = NOP 1512 1513 # vim: tabstop=4 expandtab shiftwidth=4