src/third_party/cython/src/Cython/CodeWriter.py

   1 """
   2 Serializes a Cython code tree to Cython code. This is primarily useful for
   3 debugging and testing purposes.
   4
   5 The output is in a strict format, no whitespace or comments from the input
   6 is preserved (and it could not be as it is not present in the code tree).
   7 """
   8
   9 from Cython.Compiler.Visitor import TreeVisitor
  10 from Cython.Compiler.ExprNodes import *
  11
  12 class LinesResult(object):
  13     def __init__(self):
  14         self.lines = []
  15         self.s = u""
  16
  17     def put(self, s):
  18         self.s += s
  19
  20     def newline(self):
  21         self.lines.append(self.s)
  22         self.s = u""
  23
  24     def putline(self, s):
  25         self.put(s)
  26         self.newline()
  27
  28 class DeclarationWriter(TreeVisitor):
  29
  30     indent_string = u"    "
  31
  32     def __init__(self, result = None):
  33         super(DeclarationWriter, self).__init__()
  34         if result is None:
  35             result = LinesResult()
  36         self.result = result
  37         self.numindents = 0
  38         self.tempnames = {}
  39         self.tempblockindex = 0
  40
  41     def write(self, tree):
  42         self.visit(tree)
  43         return self.result
  44
  45     def indent(self):
  46         self.numindents += 1
  47
  48     def dedent(self):
  49         self.numindents -= 1
  50
  51     def startline(self, s = u""):
  52         self.result.put(self.indent_string * self.numindents + s)
  53
  54     def put(self, s):
  55         self.result.put(s)
  56
  57     def putline(self, s):
  58         self.result.putline(self.indent_string * self.numindents + s)
  59
  60     def endline(self, s = u""):
  61         self.result.putline(s)
  62
  63     def line(self, s):
  64         self.startline(s)
  65         self.endline()
  66
  67     def comma_separated_list(self, items, output_rhs=False):
  68         if len(items) > 0:
  69             for item in items[:-1]:
  70                 self.visit(item)
  71                 if output_rhs and item.default is not None:
  72                     self.put(u" = ")
  73                     self.visit(item.default)
  74                 self.put(u", ")
  75             self.visit(items[-1])
  76
  77     def visit_Node(self, node):
  78         raise AssertionError("Node not handled by serializer: %r" % node)
  79
  80     def visit_ModuleNode(self, node):
  81         self.visitchildren(node)
  82
  83     def visit_StatListNode(self, node):
  84         self.visitchildren(node)
  85
  86     def visit_CDefExternNode(self, node):
  87         if node.include_file is None:
  88             file = u'*'
  89         else:
  90             file = u'"%s"' % node.include_file
  91         self.putline(u"cdef extern from %s:" % file)
  92         self.indent()
  93         self.visit(node.body)
  94         self.dedent()
  95
  96     def visit_CPtrDeclaratorNode(self, node):
  97         self.put('*')
  98         self.visit(node.base)
  99
 100     def visit_CReferenceDeclaratorNode(self, node):
 101         self.put('&')
 102         self.visit(node.base)
 103
 104     def visit_CArrayDeclaratorNode(self, node):
 105         self.visit(node.base)
 106         self.put(u'[')
 107         if node.dimension is not None:
 108             self.visit(node.dimension)
 109         self.put(u']')
 110
 111     def visit_CArrayDeclaratorNode(self, node):
 112         self.visit(node.base)
 113         self.put(u'[')
 114         if node.dimension is not None:
 115             self.visit(node.dimension)
 116         self.put(u']')
 117
 118     def visit_CFuncDeclaratorNode(self, node):
 119         # TODO: except, gil, etc.
 120         self.visit(node.base)
 121         self.put(u'(')
 122         self.comma_separated_list(node.args)
 123         self.endline(u')')
 124
 125     def visit_CNameDeclaratorNode(self, node):
 126         self.put(node.name)
 127
 128     def visit_CSimpleBaseTypeNode(self, node):
 129         # See Parsing.p_sign_and_longness
 130         if node.is_basic_c_type:
 131             self.put(("unsigned ", "", "signed ")[node.signed])
 132             if node.longness < 0:
 133                 self.put("short " * -node.longness)
 134             elif node.longness > 0:
 135                 self.put("long " * node.longness)
 136         self.put(node.name)
 137
 138     def visit_CComplexBaseTypeNode(self, node):
 139         self.put(u'(')
 140         self.visit(node.base_type)
 141         self.visit(node.declarator)
 142         self.put(u')')
 143
 144     def visit_CNestedBaseTypeNode(self, node):
 145         self.visit(node.base_type)
 146         self.put(u'.')
 147         self.put(node.name)
 148
 149     def visit_TemplatedTypeNode(self, node):
 150         self.visit(node.base_type_node)
 151         self.put(u'[')
 152         self.comma_separated_list(node.positional_args + node.keyword_args.key_value_pairs)
 153         self.put(u']')
 154
 155     def visit_CVarDefNode(self, node):
 156         self.startline(u"cdef ")
 157         self.visit(node.base_type)
 158         self.put(u" ")
 159         self.comma_separated_list(node.declarators, output_rhs=True)
 160         self.endline()
 161
 162     def visit_container_node(self, node, decl, extras, attributes):
 163         # TODO: visibility
 164         self.startline(decl)
 165         if node.name:
 166             self.put(u' ')
 167             self.put(node.name)
 168             if node.cname is not None:
 169                 self.put(u' "%s"' % node.cname)
 170         if extras:
 171             self.put(extras)
 172         self.endline(':')
 173         self.indent()
 174         if not attributes:
 175             self.putline('pass')
 176         else:
 177             for attribute in attributes:
 178                 self.visit(attribute)
 179         self.dedent()
 180
 181     def visit_CStructOrUnionDefNode(self, node):
 182         if node.typedef_flag:
 183             decl = u'ctypedef '
 184         else:
 185             decl = u'cdef '
 186         if node.visibility == 'public':
 187             decl += u'public '
 188         if node.packed:
 189             decl += u'packed '
 190         decl += node.kind
 191         self.visit_container_node(node, decl, None, node.attributes)
 192
 193     def visit_CppClassNode(self, node):
 194         extras = ""
 195         if node.templates:
 196             extras = u"[%s]" % ", ".join(node.templates)
 197         if node.base_classes:
 198             extras += "(%s)" % ", ".join(node.base_classes)
 199         self.visit_container_node(node, u"cdef cppclass", extras, node.attributes)
 200
 201     def visit_CEnumDefNode(self, node):
 202         self.visit_container_node(node, u"cdef enum", None, node.items)
 203
 204     def visit_CEnumDefItemNode(self, node):
 205         self.startline(node.name)
 206         if node.cname:
 207             self.put(u' "%s"' % node.cname)
 208         if node.value:
 209             self.put(u" = ")
 210             self.visit(node.value)
 211         self.endline()
 212
 213     def visit_CClassDefNode(self, node):
 214         assert not node.module_name
 215         if node.decorators:
 216             for decorator in node.decorators:
 217                 self.visit(decorator)
 218         self.startline(u"cdef class ")
 219         self.put(node.class_name)
 220         if node.base_class_name:
 221             self.put(u"(")
 222             if node.base_class_module:
 223                 self.put(node.base_class_module)
 224                 self.put(u".")
 225             self.put(node.base_class_name)
 226             self.put(u")")
 227         self.endline(u":")
 228         self.indent()
 229         self.visit(node.body)
 230         self.dedent()
 231
 232     def visit_CTypeDefNode(self, node):
 233         self.startline(u"ctypedef ")
 234         self.visit(node.base_type)
 235         self.put(u" ")
 236         self.visit(node.declarator)
 237         self.endline()
 238
 239     def visit_FuncDefNode(self, node):
 240         self.startline(u"def %s(" % node.name)
 241         self.comma_separated_list(node.args)
 242         self.endline(u"):")
 243         self.indent()
 244         self.visit(node.body)
 245         self.dedent()
 246
 247     def visit_CArgDeclNode(self, node):
 248         if node.base_type.name is not None:
 249             self.visit(node.base_type)
 250             self.put(u" ")
 251         self.visit(node.declarator)
 252         if node.default is not None:
 253             self.put(u" = ")
 254             self.visit(node.default)
 255
 256     def visit_CImportStatNode(self, node):
 257         self.startline(u"cimport ")
 258         self.put(node.module_name)
 259         if node.as_name:
 260             self.put(u" as ")
 261             self.put(node.as_name)
 262         self.endline()
 263
 264     def visit_FromCImportStatNode(self, node):
 265         self.startline(u"from ")
 266         self.put(node.module_name)
 267         self.put(u" cimport ")
 268         first = True
 269         for pos, name, as_name, kind in node.imported_names:
 270             assert kind is None
 271             if first:
 272                 first = False
 273             else:
 274                 self.put(u", ")
 275             self.put(name)
 276             if as_name:
 277                 self.put(u" as ")
 278                 self.put(as_name)
 279         self.endline()
 280
 281     def visit_NameNode(self, node):
 282         self.put(node.name)
 283
 284     def visit_IntNode(self, node):
 285         self.put(node.value)
 286
 287     def visit_NoneNode(self, node):
 288         self.put(u"None")
 289
 290     def visit_NotNode(self, node):
 291         self.put(u"(not ")
 292         self.visit(node.operand)
 293         self.put(u")")
 294
 295     def visit_DecoratorNode(self, node):
 296         self.startline("@")
 297         self.visit(node.decorator)
 298         self.endline()
 299
 300     def visit_BinopNode(self, node):
 301         self.visit(node.operand1)
 302         self.put(u" %s " % node.operator)
 303         self.visit(node.operand2)
 304
 305     def visit_AttributeNode(self, node):
 306         self.visit(node.obj)
 307         self.put(u".%s" % node.attribute)
 308
 309     def visit_BoolNode(self, node):
 310         self.put(str(node.value))
 311
 312     # FIXME: represent string nodes correctly
 313     def visit_StringNode(self, node):
 314         value = node.value
 315         if value.encoding is not None:
 316             value = value.encode(value.encoding)
 317         self.put(repr(value))
 318
 319     def visit_PassStatNode(self, node):
 320         self.startline(u"pass")
 321         self.endline()
 322
 323 class CodeWriter(DeclarationWriter):
 324
 325     def visit_SingleAssignmentNode(self, node):
 326         self.startline()
 327         self.visit(node.lhs)
 328         self.put(u" = ")
 329         self.visit(node.rhs)
 330         self.endline()
 331
 332     def visit_CascadedAssignmentNode(self, node):
 333         self.startline()
 334         for lhs in node.lhs_list:
 335             self.visit(lhs)
 336             self.put(u" = ")
 337         self.visit(node.rhs)
 338         self.endline()
 339
 340     def visit_PrintStatNode(self, node):
 341         self.startline(u"print ")
 342         self.comma_separated_list(node.arg_tuple.args)
 343         if not node.append_newline:
 344             self.put(u",")
 345         self.endline()
 346
 347     def visit_ForInStatNode(self, node):
 348         self.startline(u"for ")
 349         self.visit(node.target)
 350         self.put(u" in ")
 351         self.visit(node.iterator.sequence)
 352         self.endline(u":")
 353         self.indent()
 354         self.visit(node.body)
 355         self.dedent()
 356         if node.else_clause is not None:
 357             self.line(u"else:")
 358             self.indent()
 359             self.visit(node.else_clause)
 360             self.dedent()
 361
 362     def visit_IfStatNode(self, node):
 363         # The IfClauseNode is handled directly without a seperate match
 364         # for clariy.
 365         self.startline(u"if ")
 366         self.visit(node.if_clauses[0].condition)
 367         self.endline(":")
 368         self.indent()
 369         self.visit(node.if_clauses[0].body)
 370         self.dedent()
 371         for clause in node.if_clauses[1:]:
 372             self.startline("elif ")
 373             self.visit(clause.condition)
 374             self.endline(":")
 375             self.indent()
 376             self.visit(clause.body)
 377             self.dedent()
 378         if node.else_clause is not None:
 379             self.line("else:")
 380             self.indent()
 381             self.visit(node.else_clause)
 382             self.dedent()
 383
 384     def visit_SequenceNode(self, node):
 385         self.comma_separated_list(node.args) # Might need to discover whether we need () around tuples...hmm...
 386
 387     def visit_SimpleCallNode(self, node):
 388         self.visit(node.function)
 389         self.put(u"(")
 390         self.comma_separated_list(node.args)
 391         self.put(")")
 392
 393     def visit_GeneralCallNode(self, node):
 394         self.visit(node.function)
 395         self.put(u"(")
 396         posarg = node.positional_args
 397         if isinstance(posarg, AsTupleNode):
 398             self.visit(posarg.arg)
 399         else:
 400             self.comma_separated_list(posarg)
 401         if node.keyword_args is not None or node.starstar_arg is not None:
 402             raise Exception("Not implemented yet")
 403         self.put(u")")
 404
 405     def visit_ExprStatNode(self, node):
 406         self.startline()
 407         self.visit(node.expr)
 408         self.endline()
 409
 410     def visit_InPlaceAssignmentNode(self, node):
 411         self.startline()
 412         self.visit(node.lhs)
 413         self.put(u" %s= " % node.operator)
 414         self.visit(node.rhs)
 415         self.endline()
 416
 417     def visit_WithStatNode(self, node):
 418         self.startline()
 419         self.put(u"with ")
 420         self.visit(node.manager)
 421         if node.target is not None:
 422             self.put(u" as ")
 423             self.visit(node.target)
 424         self.endline(u":")
 425         self.indent()
 426         self.visit(node.body)
 427         self.dedent()
 428
 429     def visit_TryFinallyStatNode(self, node):
 430         self.line(u"try:")
 431         self.indent()
 432         self.visit(node.body)
 433         self.dedent()
 434         self.line(u"finally:")
 435         self.indent()
 436         self.visit(node.finally_clause)
 437         self.dedent()
 438
 439     def visit_TryExceptStatNode(self, node):
 440         self.line(u"try:")
 441         self.indent()
 442         self.visit(node.body)
 443         self.dedent()
 444         for x in node.except_clauses:
 445             self.visit(x)
 446         if node.else_clause is not None:
 447             self.visit(node.else_clause)
 448
 449     def visit_ExceptClauseNode(self, node):
 450         self.startline(u"except")
 451         if node.pattern is not None:
 452             self.put(u" ")
 453             self.visit(node.pattern)
 454         if node.target is not None:
 455             self.put(u", ")
 456             self.visit(node.target)
 457         self.endline(":")
 458         self.indent()
 459         self.visit(node.body)
 460         self.dedent()
 461
 462     def visit_ReturnStatNode(self, node):
 463         self.startline("return ")
 464         self.visit(node.value)
 465         self.endline()
 466
 467     def visit_ReraiseStatNode(self, node):
 468         self.line("raise")
 469
 470     def visit_ImportNode(self, node):
 471         self.put(u"(import %s)" % node.module_name.value)
 472
 473     def visit_TempsBlockNode(self, node):
 474         """
 475         Temporaries are output like $1_1', where the first number is
 476         an index of the TempsBlockNode and the second number is an index
 477         of the temporary which that block allocates.
 478         """
 479         idx = 0
 480         for handle in node.temps:
 481             self.tempnames[handle] = "$%d_%d" % (self.tempblockindex, idx)
 482             idx += 1
 483         self.tempblockindex += 1
 484         self.visit(node.body)
 485
 486     def visit_TempRefNode(self, node):
 487         self.put(self.tempnames[node.handle])
 488
 489
 490 class PxdWriter(DeclarationWriter):
 491     def __call__(self, node):
 492         print u'\n'.join(self.write(node).lines)
 493         return node
 494
 495     def visit_CFuncDefNode(self, node):
 496         if 'inline' in node.modifiers:
 497             return
 498         if node.overridable:
 499             self.startline(u'cpdef ')
 500         else:
 501             self.startline(u'cdef ')
 502         if node.visibility != 'private':
 503             self.put(node.visibility)
 504             self.put(u' ')
 505         if node.api:
 506             self.put(u'api ')
 507         self.visit(node.declarator)
 508
 509     def visit_StatNode(self, node):
 510         pass
 511
 512