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 elif isinstance(value, Module): 844 self.store_module_attr(attrname, value) 845 846 elif isinstance(value, Class): 847 self.store_class_attr(attrname, value) 848 849 # Note usage of the attribute where a local is involved. 850 851 else: 852 self._visitAttrUser(expr, attrname, node, self.expr) 853 854 else: 855 self.use_name(attrname, node) 856 857 def visitAssList(self, node): 858 859 # Declare names which will be used by generated code. 860 861 self.use_name("__getitem__", node) 862 863 # Process the assignment. 864 865 for i, n in enumerate(node.nodes): 866 self.dispatch(n) 867 self._visitConst(i) # for __getitem__(i) at run-time 868 869 def visitAssName(self, node): 870 if node.flags == "OP_DELETE": 871 print >>sys.stderr, "Warning: deletion of attribute %r in %r is not supported." % (node.name, self.full_name()) 872 #raise InspectError("Deletion of attribute %r is not supported." % node.name) 873 self._visitAssName(node) 874 875 def _visitAssName(self, node): 876 self.store(node.name, self.expr) 877 self.define_attribute_user(node) 878 879 # Ensure the presence of the given name in this namespace. 880 # NOTE: Consider not registering assignments involving methods, since 881 # NOTE: this is merely creating aliases for such methods. 882 883 if isinstance(self.get_namespace(), (Class, Module)): 884 if not isinstance(self.expr, Attr) or not isinstance(self.expr.get_value(), Function): 885 self.use_specific_attribute(None, node.name) 886 else: 887 fn = self.expr.get_value() 888 ns = self.get_namespace().full_name() 889 self.use_specific_attribute(fn.parent.full_name(), fn.name, "%s.%s" % (ns, node.name)) 890 891 visitAssTuple = visitAssList 892 893 def visitAugAssign(self, node): 894 895 # Accounting. 896 897 operator_fn = operator_functions.get(node.op) 898 operator_module = self._ensureOperators(node) 899 self.use_specific_attribute(operator_module.full_name(), operator_fn) 900 901 # Process the assignment. 902 903 self.expr = self.dispatch(node.expr) 904 905 # NOTE: Similar to micropython.ast handler code. 906 # NOTE: Slices and subscripts are supported by __setitem__(slice) and 907 # NOTE: not __setslice__. 908 909 if isinstance(node.node, compiler.ast.Name): 910 self._visitAssName(node.node) 911 elif isinstance(node.node, compiler.ast.Getattr): 912 self.visitAssAttr(node.node) 913 else: 914 self.dispatch(node.node) 915 self.use_specific_attribute("__builtins__", "slice") 916 self.use_name("__setitem__", node) 917 918 visitBackquote = OP 919 920 visitBitand = _visitOperator 921 922 visitBitor = _visitOperator 923 924 visitBitxor = _visitOperator 925 926 def visitBreak(self, node): 927 self.NOP(node) 928 self.suspend_broken_branch() 929 930 visitCallFunc = OP 931 932 def visitClass(self, node): 933 934 """ 935 Register the class at the given 'node' subject to the restrictions 936 mentioned in the module docstring. 937 """ 938 939 if self.namespaces: 940 print >>sys.stderr, "Warning: class %r in %r is not global: ignored." % (node.name, self.namespaces[-1].full_name()) 941 return 942 else: 943 if self.in_loop: 944 print >>sys.stderr, "Warning: class %r in %r defined in a loop." % (node.name, self.full_name()) 945 946 cls = get_class(node.name, self.get_namespace(), self, node) 947 948 # Make a back reference from the node for code generation. 949 950 node.unit = cls 951 952 # Process base classes in the context of the class's namespace. 953 # This confines references to such classes to the class instead of 954 # the namespace in which it is defined. 955 956 self.namespaces.append(cls) 957 958 # Visit the base class expressions, attempting to find concrete 959 # definitions of classes. 960 961 for base in node.bases: 962 expr = self.dispatch(base) 963 964 # Each base class must be constant and known at compile-time. 965 966 if isinstance(expr, Attr): 967 if expr.assignments != 1: 968 raise InspectError("Base class %r for %r is not constant: %r" % (base, cls.full_name(), expr)) 969 elif not isinstance(expr.get_value(), Class): 970 raise InspectError("Base class %r for %r is not a class: %r" % (base, cls.full_name(), expr.get_value())) 971 else: 972 cls.add_base(expr.get_value()) 973 974 # Where no expression value is available, the base class is 975 # not identifiable. 976 977 else: 978 raise InspectError("Base class %r for %r is not found: it may be hidden in some way." % (base, cls.full_name())) 979 980 # NOTE: Potentially dubious measure to permit __init__ availability. 981 # If no bases exist, adopt the 'object' class. 982 983 if not node.bases and not (self.name == "__builtins__" and node.name == "object"): 984 expr = self.dispatch(compiler.ast.Name("object")) 985 cls.add_base(expr.get_value()) 986 987 # Make an entry for the class in the parent namespace. 988 989 self.namespaces.pop() 990 self.store(node.name, cls) 991 self.add_object(cls) 992 993 # Process the class body in its own namespace. 994 # Add __name__ to the namespace. 995 996 self.namespaces.append(cls) 997 self.store("__name__", self._visitConst(node.name)) 998 self.dispatch(node.code) 999 self.namespaces.pop() 1000 1001 cls.finalise_attribute_usage() 1002 return cls 1003 1004 def visitCompare(self, node): 1005 1006 # Accounting. 1007 # NOTE: Replicates some code in micropython.ast.visitCompare. 1008 1009 self.use_name("__bool__", node) 1010 1011 this_node = node 1012 1013 for op in node.ops: 1014 op_name, next_node = op 1015 1016 # Define name/attribute usage. 1017 # Get the applicable operation. 1018 1019 operator_fn = operator_functions.get(op_name) 1020 1021 # For operators, reference the specific function involved. 1022 1023 if operator_fn is not None: 1024 operator_module = self._ensureOperators(node) 1025 self.use_specific_attribute(operator_module.full_name(), operator_fn) 1026 1027 # Define __contains__ usage on the next node. 1028 1029 elif op_name.endswith("in"): 1030 self.use_name("__contains__", next_node) 1031 1032 this_node = next_node 1033 1034 return self.OP(node) 1035 1036 def visitConst(self, node): 1037 return self._visitConst(node.value) 1038 1039 def visitContinue(self, node): 1040 self.NOP(node) 1041 self.suspend_continuing_branch() 1042 1043 visitDecorators = NOP 1044 1045 visitDict = OP 1046 1047 visitDiscard = NOP 1048 1049 visitDiv = _visitOperator 1050 1051 visitEllipsis = NOP 1052 1053 visitExec = NOP 1054 1055 visitExpression = OP 1056 1057 visitFloorDiv = _visitOperator 1058 1059 def visitFor(self, node): 1060 self.new_branchpoint(node) 1061 1062 # Declare names which will be used by generated code. 1063 1064 self.use_name("__iter__", node.list) 1065 self.use_name("next") 1066 self.use_name("StopIteration") 1067 1068 in_loop = self.in_loop 1069 self.in_loop = True 1070 self.dispatch(node.list) 1071 1072 # NOTE: Could generate AST nodes for the actual operations instead of 1073 # NOTE: manually generating code in micropython.ast. 1074 1075 self.expr = make_instance() # each element is a result of a function call 1076 self.dispatch(node.assign) 1077 1078 # Enter the loop. 1079 # Propagate attribute usage to branches. 1080 1081 self.new_branch(node) 1082 self.dispatch(node.body) 1083 1084 self.resume_continuing_branches() 1085 1086 self.shelve_branch() 1087 1088 self.in_loop = in_loop 1089 1090 # A null branch is used to record a path around the loop. 1091 1092 self.new_branch(node.else_ or NullBranch()) 1093 self.shelve_branch() 1094 1095 self.merge_branches() 1096 1097 # The else clause is evaluated outside any branch. 1098 1099 if node.else_ is not None: 1100 self.dispatch(node.else_) 1101 1102 # Any suspended branches from the loop can now be resumed. 1103 1104 self.resume_broken_branches() 1105 1106 def visitFrom(self, node): 1107 module = self.complete_import(node.modname, True) 1108 1109 for name, alias in node.names: 1110 1111 # For specific names, obtain and store referenced objects using 1112 # the name or any alias provided in the current namespace. 1113 1114 if name != "*": 1115 if module: 1116 1117 # Missing names may refer to submodules. 1118 1119 submodule = self.complete_import(node.modname + "." + name, True) 1120 if submodule: 1121 if not module.has_key(name): 1122 module.store(name, submodule) 1123 1124 # Complete the import if the name was found. 1125 1126 if module.has_key(name): 1127 attr = module[name] 1128 self.store(alias or name, attr) 1129 self.use_specific_attribute(module.full_name(), name) 1130 continue 1131 1132 # Support the import of names from missing modules. 1133 1134 self.store(alias or name, UnresolvedName(name, node.modname, self)) 1135 1136 # For wildcards, obtain and store all objects from a module in the 1137 # current namespace. 1138 1139 else: 1140 if module: 1141 for n in module.keys(): 1142 attr = module[n] 1143 self.store(n, attr) 1144 self.use_specific_attribute(module.full_name(), n) 1145 1146 def visitFunction(self, node): 1147 return self._visitFunction(node, node.name) 1148 1149 visitGenExpr = OP 1150 1151 visitGenExprFor = NOP 1152 1153 visitGenExprIf = NOP 1154 1155 visitGenExprInner = NOP 1156 1157 def visitGetattr(self, node): 1158 expr = self.dispatch(node.expr) 1159 attrname = node.attrname 1160 node._attr = self._visitAttr(expr, attrname, node) 1161 return node._attr 1162 1163 def visitGlobal(self, node): 1164 if self.namespaces: 1165 for name in node.names: 1166 ns = self.namespaces[-1] 1167 if not ns.make_global(name): 1168 raise InspectError("Name %r is global and local in %r" % (name, ns.full_name())) 1169 1170 # The name is recorded in an earlier process. 1171 1172 def visitIf(self, node): 1173 self.use_name("__bool__", node) 1174 self.new_branchpoint() 1175 1176 # Propagate attribute usage to branches. 1177 1178 for test, body in node.tests: 1179 self.dispatch(test) 1180 1181 self.new_branch(body) 1182 self.dispatch(body) 1183 self.shelve_branch() 1184 1185 # Maintain a branch for the else clause. 1186 1187 self.new_branch(node.else_ or NullBranch()) 1188 if node.else_ is not None: 1189 self.dispatch(node.else_) 1190 self.shelve_branch() 1191 1192 self.merge_branches() 1193 1194 def visitIfExp(self, node): 1195 self.use_name("__bool__", node) 1196 self.new_branchpoint() 1197 1198 # Propagate attribute usage to branches. 1199 1200 self.dispatch(node.test) 1201 1202 self.new_branch(node.then) 1203 self.dispatch(node.then) 1204 self.shelve_branch() 1205 1206 self.new_branch(node.else_) 1207 self.dispatch(node.else_) 1208 self.shelve_branch() 1209 1210 self.merge_branches() 1211 return make_instance() # either outcome is possible 1212 1213 def visitImport(self, node): 1214 for name, alias in node.names: 1215 module = self.complete_import(name, alias) 1216 if alias is not None: 1217 self.store(alias, module or UnresolvedName(None, name, self)) 1218 else: 1219 name_used = name.split(".")[0] 1220 self.store(name_used, module or UnresolvedName(None, name_used, self)) 1221 1222 visitInvert = _visitOperator 1223 1224 def visitKeyword(self, node): 1225 self.dispatch(node.expr) 1226 self._visitConst(node.name) 1227 self.keyword_names.add(node.name) 1228 1229 def visitLambda(self, node): 1230 fn = self._visitFunction(node, None) 1231 self.use_specific_attribute(None, fn.name) 1232 return fn 1233 1234 visitLeftShift = _visitOperator 1235 1236 def visitList(self, node): 1237 self.use_specific_attribute("__builtins__", "list") 1238 return self.OP(node) 1239 1240 def visitListComp(self, node): 1241 1242 # Note that explicit dispatch is performed. 1243 1244 if node.quals: 1245 self.visitListCompFor(node.quals[0], node.quals[1:], node.expr) 1246 return make_instance() 1247 1248 def visitListCompFor(self, node, following_quals, expr): 1249 self.new_branchpoint() 1250 1251 # Declare names which will be used by generated code. 1252 1253 self.use_name("__iter__", node.list) 1254 self.use_name("next") 1255 1256 in_loop = self.in_loop 1257 self.in_loop = True 1258 self.dispatch(node.list) 1259 1260 # NOTE: Could generate AST nodes for the actual operations instead of 1261 # NOTE: manually generating code in micropython.ast. 1262 1263 self.expr = make_instance() # each element is a result of a function call 1264 self.dispatch(node.assign) 1265 1266 # Enter the loop. 1267 # Propagate attribute usage to branches. 1268 1269 self.new_branch(node) 1270 1271 # Note that explicit dispatch is performed. 1272 1273 if node.ifs: 1274 self.visitListCompIf(node.ifs[0], node.ifs[1:], following_quals, expr) 1275 elif following_quals: 1276 self.visitListCompFor(following_quals[0], following_quals[1:], expr) 1277 else: 1278 self.dispatch(expr) 1279 1280 self.shelve_branch() 1281 self.in_loop = in_loop 1282 1283 self.merge_branches() 1284 1285 def visitListCompIf(self, node, following_ifs, following_quals, expr): 1286 self.use_name("__bool__", node) 1287 self.new_branchpoint() 1288 1289 # Propagate attribute usage to branches. 1290 1291 self.dispatch(node.test) 1292 1293 # Note that explicit dispatch is performed. 1294 1295 if following_ifs: 1296 self.visitListCompIf(following_ifs[0], following_ifs[1:], following_quals, expr) 1297 elif following_quals: 1298 self.visitListCompFor(following_quals[0], following_quals[1:], expr) 1299 else: 1300 self.new_branch(expr) 1301 self.dispatch(expr) 1302 self.shelve_branch() 1303 1304 # Maintain a branch for the else clause. 1305 1306 self.new_branch(NullBranch()) 1307 self.shelve_branch() 1308 1309 self.merge_branches() 1310 1311 visitMod = _visitOperator 1312 1313 def visitModule(self, node): 1314 1315 # Make a back reference from the node for code generation. 1316 1317 node.unit = self 1318 return self.dispatch(node.node) 1319 1320 visitMul = _visitOperator 1321 1322 def visitName(self, node): 1323 attr = self.get_namespace().get_using_node(node.name, node) or make_instance() 1324 node._attr = attr 1325 return attr 1326 1327 def visitNot(self, node): 1328 self.use_name("__bool__", node) 1329 self.dispatch(node.expr) 1330 return make_instance() 1331 1332 visitOr = TEST_OP 1333 1334 visitPass = NOP 1335 1336 visitPower = _visitOperator 1337 1338 def _visitPrint(self, node, function_name): 1339 self.NOP(node) 1340 self.use_specific_attribute("__builtins__", function_name) 1341 1342 def visitPrint(self, node): 1343 self._visitPrint(node, "_print") 1344 1345 def visitPrintnl(self, node): 1346 self._visitPrint(node, "_printnl") 1347 1348 visitRaise = NOP_ABANDON 1349 1350 visitReturn = NOP_ABANDON 1351 1352 visitRightShift = _visitOperator 1353 1354 def visitSlice(self, node): 1355 return self._visitOperator(node, self.in_assignment and "AssSlice" or "Slice") 1356 1357 visitSliceobj = OP 1358 1359 def visitStmt(self, node): 1360 for n in node.nodes: 1361 self.dispatch(n) 1362 1363 visitSub = _visitOperator 1364 1365 def visitSubscript(self, node): 1366 return self._visitOperator(node, self.in_assignment and "AssSubscript" or "Subscript") 1367 1368 def visitTryExcept(self, node): 1369 self.new_branchpoint() 1370 self.dispatch(node.body) 1371 1372 for name, var, n in node.handlers: 1373 if name is not None: 1374 self.dispatch(name) 1375 1376 self.new_branch(n) 1377 1378 # Any abandoned branches from the body can now be resumed. 1379 1380 self.resume_abandoned_branches() 1381 1382 # Establish the local for the handler. 1383 1384 if var is not None: 1385 self.dispatch(var) 1386 if n is not None: 1387 self.dispatch(n) 1388 1389 self.shelve_branch() 1390 1391 # The else clause maintains the usage from the body but without the 1392 # abandoned branches since they would never lead to the else clause 1393 # being executed. 1394 1395 self.new_branch(node.else_ or NullBranch()) 1396 if node.else_ is not None: 1397 self.dispatch(node.else_) 1398 self.shelve_branch() 1399 1400 self.merge_branches() 1401 1402 visitTryFinally = NOP 1403 1404 visitTuple = OP 1405 1406 visitUnaryAdd = _visitOperator 1407 1408 visitUnarySub = _visitOperator 1409 1410 def visitWhile(self, node): 1411 self.use_name("__bool__", node) 1412 self.new_branchpoint(node) 1413 1414 # Propagate attribute usage to branches. 1415 1416 in_loop = self.in_loop 1417 self.in_loop = True 1418 1419 # The test is evaluated initially and again in the loop. 1420 1421 self.dispatch(node.test) 1422 1423 self.new_branch(node) 1424 self.dispatch(node.body) 1425 1426 self.resume_continuing_branches() 1427 1428 self.dispatch(node.test) 1429 self.shelve_branch() 1430 1431 self.in_loop = in_loop 1432 1433 # A null branch is used to record a path around the loop. 1434 1435 self.new_branch(node.else_ or NullBranch()) 1436 self.shelve_branch() 1437 1438 self.merge_branches() 1439 1440 # The else clause is evaluated outside any branch. 1441 1442 if node.else_ is not None: 1443 self.dispatch(node.else_) 1444 1445 # Any suspended branches from the loop can now be resumed. 1446 1447 self.resume_broken_branches() 1448 1449 visitWith = NOP 1450 1451 visitYield = NOP 1452 1453 # vim: tabstop=4 expandtab shiftwidth=4