# Copyright (c) 2015-2019 by Rocky Bernstein # Copyright (c) 2005 by Dan Pascu # Copyright (c) 2000-2002 by hartmut Goebel # Copyright (c) 1999 John Aycock # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . """Creates Python source code from an uncompyle6 parse tree. The terminal symbols are CPython bytecode instructions. (See the python documentation under module "dis" for a list of instructions and what they mean). Upper levels of the grammar is a more-or-less conventional grammar for Python. """ # The below is a bit long, but still it is somehwat abbreviated. # See https://github.com/rocky/python-uncompyle6/wiki/Table-driven-semantic-actions. # for a more complete explanation, nicely marked up and with examples. # # # Semantic action rules for nonterminal symbols can be specified here by # creating a method prefaced with "n_" for that nonterminal. For # example, "n_exec_stmt" handles the semantic actions for the # "exec_stmt" nonterminal symbol. Similarly if a method with the name # of the nonterminal is suffixed with "_exit" it will be called after # all of its children are called. # # After a while writing methods this way, you'll find many routines which do similar # sorts of things, and soon you'll find you want a short notation to # describe rules and not have to create methods at all. # # So another other way to specify a semantic rule for a nonterminal is via # one of the tables MAP_R0, MAP_R, or MAP_DIRECT where the key is the # nonterminal name. # # These dictionaries use a printf-like syntax to direct substitution # from attributes of the nonterminal and its children.. # # The rest of the below describes how table-driven semantic actions work # and gives a list of the format specifiers. The default() and # template_engine() methods implement most of the below. # # We allow for a couple of ways to interact with a node in a tree. So # step 1 after not seeing a custom method for a nonterminal is to # determine from what point of view tree-wise the rule is applied. # In the diagram below, N is a nonterminal name, and K also a nonterminal # name but the one used as a key in the table. # we show where those are with respect to each other in the # parse tree for N. # # # N&K N N # / | ... \ / | ... \ / | ... \ # O O O O O K O O O # | # K # TABLE_DIRECT TABLE_R TABLE_R0 # # The default table is TABLE_DIRECT mapping By far, most rules used work this way. # TABLE_R0 is rarely used. # # The key K is then extracted from the subtree and used to find one # of the tables, T listed above. The result after applying T[K] is # a format string and arguments (a la printf()) for the formatting # engine. # # Escapes in the format string are: # # %c evaluate the node recursively. Its argument is a single # integer or tuple representing a node index. # If a tuple is given, the first item is the node index while # the second item is a string giving the node/noterminal name. # This name will be checked at runtime against the node type. # # %p like %c but sets the operator precedence. # Its argument then is a tuple indicating the node # index and the precidence value, an integer. # # %C evaluate children recursively, with sibling children separated by the # given string. It needs a 3-tuple: a starting node, the maximimum # value of an end node, and a string to be inserted between sibling children # # %, Append ',' if last %C only printed one item. This is mostly for tuples # on the LHS of an assignment statement since BUILD_TUPLE_n pretty-prints # other tuples. The specifier takes no arguments # # %P same as %C but sets operator precedence. Its argument is a 4-tuple: # the node low and high indices, the separator, a string the precidence # value, an integer. # # %D Same as `%C` this is for left-recursive lists like kwargs where goes # to epsilon at the beginning. It needs a 3-tuple: a starting node, the # maximimum value of an end node, and a string to be inserted between # sibling children. If we were to use `%C` an extra separator with an # epsilon would appear at the beginning. # # %| Insert spaces to the current indentation level. Takes no arguments. # # %+ increase current indentation level. Takes no arguments. # # %- decrease current indentation level. Takes no arguments. # # %{...} evaluate ... in context of N # # %% literal '%'. Takes no arguments. # # # The '%' may optionally be followed by a number (C) in square # brackets, which makes the template_engine walk down to N[C] before # evaluating the escape code. import sys IS_PYPY = '__pypy__' in sys.builtin_module_names PYTHON3 = (sys.version_info >= (3, 0)) from xdis.code import iscode from xdis.util import COMPILER_FLAG_BIT from uncompyle6.parser import get_python_parser from uncompyle6.parsers.treenode import SyntaxTree from spark_parser import GenericASTTraversal, DEFAULT_DEBUG as PARSER_DEFAULT_DEBUG from uncompyle6.scanner import Code, get_scanner import uncompyle6.parser as python_parser from uncompyle6.semantics.make_function import ( make_function2, make_function3 ) from uncompyle6.semantics.parser_error import ParserError from uncompyle6.semantics.check_ast import checker from uncompyle6.semantics.customize import customize_for_version from uncompyle6.semantics.helper import ( print_docstring, find_globals_and_nonlocals, flatten_list) from uncompyle6.scanners.tok import Token from uncompyle6.semantics.consts import ( LINE_LENGTH, RETURN_LOCALS, NONE, RETURN_NONE, PASS, ASSIGN_DOC_STRING, NAME_MODULE, TAB, INDENT_PER_LEVEL, TABLE_R, MAP_DIRECT, MAP, PRECEDENCE, ASSIGN_TUPLE_PARAM, escape, minint) from uncompyle6.show import ( maybe_show_tree, ) if PYTHON3: from io import StringIO else: from StringIO import StringIO def is_docstring(node): try: return (node[0][0].kind == 'assign' and node[0][0][1][0].pattr == '__doc__') except: return False class SourceWalkerError(Exception): def __init__(self, errmsg): self.errmsg = errmsg def __str__(self): return self.errmsg class SourceWalker(GenericASTTraversal, object): stacked_params = ('f', 'indent', 'is_lambda', '_globals') def __init__(self, version, out, scanner, showast=False, debug_parser=PARSER_DEFAULT_DEBUG, compile_mode='exec', is_pypy=IS_PYPY, linestarts={}, tolerate_errors=False): """`version' is the Python version (a float) of the Python dialect of both the syntax tree and language we should produce. `out' is IO-like file pointer to where the output should go. It whould have a getvalue() method. `scanner' is a method to call when we need to scan tokens. Sometimes in producing output we will run across further tokens that need to be scaned. If `showast' is True, we print the syntax tree. `compile_mode' is is either 'exec' or 'single'. It isthe compile mode that was used to create the Syntax Tree and specifies a gramar variant within a Python version to use. `is_pypy' should be True if the Syntax Tree was generated for PyPy. `linestarts' is a dictionary of line number to bytecode offset. This can sometimes assist in determinte which kind of source-code construct to use when there is ambiguity. """ GenericASTTraversal.__init__(self, ast=None) self.scanner = scanner params = { 'f': out, 'indent': '', } self.version = version self.p = get_python_parser(version, debug_parser=dict(debug_parser), compile_mode=compile_mode, is_pypy=is_pypy) self.debug_parser = dict(debug_parser) self.showast = showast self.params = params self.param_stack = [] self.ERROR = None self.prec = 100 self.return_none = False self.mod_globs = set() self.currentclass = None self.classes = [] self.pending_newlines = 0 self.linestarts = linestarts self.line_number = 1 self.ast_errors = [] # FIXME: have p.insts update in a better way # modularity is broken here self.p.insts = scanner.insts # This is in Python 2.6 on. It changes the way # strings get interpreted. See n_LOAD_CONST self.FUTURE_UNICODE_LITERALS = False # Sometimes we may want to continue decompiling when there are errors # and sometimes not self.tolerate_errors = tolerate_errors # hide_internal suppresses displaying the additional instructions that sometimes # exist in code but but were not written in the source code. # An example is: # __module__ = __name__ self.hide_internal = True self.name = None self.version = version self.is_pypy = is_pypy customize_for_version(self, is_pypy, version) return def str_with_template(self, ast): stream = sys.stdout stream.write(self.str_with_template1(ast, '', None)) stream.write('\n') def str_with_template1(self, ast, indent, sibNum=None): rv = str(ast.kind) if sibNum is not None: rv = "%2d. %s" % (sibNum, rv) enumerate_children = False if len(ast) > 1: rv += " (%d)" % (len(ast)) enumerate_children = True mapping = self._get_mapping(ast) table = mapping[0] key = ast for i in mapping[1:]: key = key[i] pass if key.kind in table: rv += ": %s" % str(table[key.kind]) rv = indent + rv indent += ' ' i = 0 for node in ast: if hasattr(node, '__repr1__'): if enumerate_children: child = self.str_with_template1(node, indent, i) else: child = self.str_with_template1(node, indent, None) else: inst = node.format(line_prefix='L.') if inst.startswith("\n"): # Nuke leading \n inst = inst[1:] if enumerate_children: child = indent + "%2d. %s" % (i, inst) else: child = indent + inst pass rv += "\n" + child i += 1 return rv def indent_if_source_nl(self, line_number, indent): if (line_number != self.line_number): self.write("\n" + self.indent + INDENT_PER_LEVEL[:-1]) return self.line_number f = property(lambda s: s.params['f'], lambda s, x: s.params.__setitem__('f', x), lambda s: s.params.__delitem__('f'), None) indent = property(lambda s: s.params['indent'], lambda s, x: s.params.__setitem__('indent', x), lambda s: s.params.__delitem__('indent'), None) is_lambda = property(lambda s: s.params['is_lambda'], lambda s, x: s.params.__setitem__('is_lambda', x), lambda s: s.params.__delitem__('is_lambda'), None) _globals = property(lambda s: s.params['_globals'], lambda s, x: s.params.__setitem__('_globals', x), lambda s: s.params.__delitem__('_globals'), None) def set_pos_info(self, node): if hasattr(node, 'linestart') and node.linestart: self.line_number = node.linestart def preorder(self, node=None): super(SourceWalker, self).preorder(node) self.set_pos_info(node) def indent_more(self, indent=TAB): self.indent += indent def indent_less(self, indent=TAB): self.indent = self.indent[:-len(indent)] def traverse(self, node, indent=None, is_lambda=False): self.param_stack.append(self.params) if indent is None: indent = self.indent p = self.pending_newlines self.pending_newlines = 0 self.params = { '_globals': {}, '_nonlocals': {}, # Python 3 has nonlocal 'f': StringIO(), 'indent': indent, 'is_lambda': is_lambda, } self.preorder(node) self.f.write('\n'*self.pending_newlines) result = self.f.getvalue() self.params = self.param_stack.pop() self.pending_newlines = p return result def write(self, *data): if (len(data) == 0) or (len(data) == 1 and data[0] == ''): return out = ''.join((str(j) for j in data)) n = 0 for i in out: if i == '\n': n += 1 if n == len(out): self.pending_newlines = max(self.pending_newlines, n) return elif n: self.pending_newlines = max(self.pending_newlines, n) out = out[n:] break else: break if self.pending_newlines > 0: self.f.write('\n'*self.pending_newlines) self.pending_newlines = 0 for i in out[::-1]: if i == '\n': self.pending_newlines += 1 else: break if self.pending_newlines: out = out[:-self.pending_newlines] if (isinstance(out, str) and not (PYTHON3 or self.FUTURE_UNICODE_LITERALS)): out = unicode(out, 'utf-8') self.f.write(out) def println(self, *data): if data and not(len(data) == 1 and data[0] == ''): self.write(*data) self.pending_newlines = max(self.pending_newlines, 1) def is_return_none(self, node): # Is there a better way? ret = (node[0] == 'ret_expr' and node[0][0] == 'expr' and node[0][0][0] == 'LOAD_CONST' and node[0][0][0].pattr is None) if self.version <= 2.6: return ret else: # FIXME: should the SyntaxTree expression be folded into # the global RETURN_NONE constant? return (ret or node == SyntaxTree('return', [SyntaxTree('ret_expr', [NONE]), Token('RETURN_VALUE')])) # Python 3.x can have be dead code as a result of its optimization? # So we'll add a # at the end of the return lambda so the rest is ignored def n_return_lambda(self, node): if 1 <= len(node) <= 2: self.preorder(node[0]) self.write(' # Avoid dead code: ') self.prune() else: # We can't comment out like above because there may be a trailing ')' # that needs to be written assert len(node) == 3 and node[2] == 'LAMBDA_MARKER' self.preorder(node[0]) self.prune() def n_return(self, node): if self.params['is_lambda']: self.preorder(node[0]) self.prune() else: self.write(self.indent, 'return') # One reason we worry over whether we use "return None" or "return" # is that inside a generator, "return None" is illegal. # Thank you, Python! if (self.return_none or not self.is_return_none(node)): self.write(' ') self.preorder(node[0]) self.println() self.prune() # stop recursing def n_return_if_stmt(self, node): if self.params['is_lambda']: self.write(' return ') self.preorder(node[0]) self.prune() else: self.write(self.indent, 'return') if self.return_none or not self.is_return_none(node): self.write(' ') self.preorder(node[0]) self.println() self.prune() # stop recursing def n_yield(self, node): if node != SyntaxTree('yield', [NONE, Token('YIELD_VALUE')]): self.template_engine(( 'yield %c', 0), node) elif self.version <= 2.4: # Early versions of Python don't allow a plain "yield" self.write('yield None') else: self.write('yield') self.prune() # stop recursing def n_build_slice3(self, node): p = self.prec self.prec = 100 if not node[0].isNone(): self.preorder(node[0]) self.write(':') if not node[1].isNone(): self.preorder(node[1]) self.write(':') if not node[2].isNone(): self.preorder(node[2]) self.prec = p self.prune() # stop recursing def n_build_slice2(self, node): p = self.prec self.prec = 100 if not node[0].isNone(): self.preorder(node[0]) self.write(':') if not node[1].isNone(): self.preorder(node[1]) self.prec = p self.prune() # stop recursing def n_expr(self, node): p = self.prec if node[0].kind.startswith('binary_expr'): n = node[0][-1][0] else: n = node[0] # if (hasattr(n, 'linestart') and n.linestart and # hasattr(self, 'current_line_number')): # self.source_linemap[self.current_line_number] = n.linestart self.prec = PRECEDENCE.get(n.kind, -2) if n == 'LOAD_CONST' and repr(n.pattr)[0] == '-': self.prec = 6 if p < self.prec: self.write('(') self.preorder(node[0]) self.write(')') else: self.preorder(node[0]) self.prec = p self.prune() def n_ret_expr(self, node): if len(node) == 1 and node[0] == 'expr': self.n_expr(node[0]) else: self.n_expr(node) n_ret_expr_or_cond = n_expr def n_binary_expr(self, node): self.preorder(node[0]) self.write(' ') self.preorder(node[-1]) self.write(' ') self.prec -= 1 self.preorder(node[1]) self.prec += 1 self.prune() def n_str(self, node): self.write(node[0].pattr) self.prune() def pp_tuple(self, tup): """Pretty print a tuple""" last_line = self.f.getvalue().split("\n")[-1] l = len(last_line)+1 indent = ' ' * l self.write('(') sep = '' for item in tup: self.write(sep) l += len(sep) s = repr(item) l += len(s) self.write(s) sep = ',' if l > LINE_LENGTH: l = 0 sep += '\n' + indent else: sep += ' ' pass pass if len(tup) == 1: self.write(", ") self.write(')') def n_LOAD_CONST(self, node): attr = node.attr data = node.pattr; datatype = type(data) if isinstance(data, float) and str(data) in frozenset(['nan', '-nan', 'inf', '-inf']): # float values 'nan' and 'inf' are not directly representable in Python at least # before 3.5 and even there it is via a library constant. # So we will canonicalize their representation as float('nan') and float('inf') self.write("float('%s')" % data) elif isinstance(datatype, int) and data == minint: # convert to hex, since decimal representation # would result in 'LOAD_CONST; UNARY_NEGATIVE' # change:hG/2002-02-07: this was done for all negative integers # todo: check whether this is necessary in Python 2.1 self.write( hex(data) ) elif datatype is type(Ellipsis): self.write('...') elif attr is None: # LOAD_CONST 'None' only occurs, when None is # implicit eg. in 'return' w/o params # pass self.write('None') elif isinstance(data, tuple): self.pp_tuple(data) elif isinstance(attr, bool): self.write(repr(attr)) elif self.FUTURE_UNICODE_LITERALS: # The FUTURE_UNICODE_LITERALS compiler flag # in 2.6 on change the way # strings are interpreted: # u'xxx' -> 'xxx' # xxx' -> b'xxx' if not PYTHON3 and isinstance(data, unicode): try: data = str(data) except UnicodeEncodeError: # Have to keep data as it is: in Unicode. pass self.write(repr(data)) elif isinstance(data, str): self.write('b'+repr(data)) else: self.write(repr(data)) else: self.write(repr(data)) # LOAD_CONST is a terminal, so stop processing/recursing early self.prune() def n_delete_subscr(self, node): if node[-2][0] == 'build_list' and node[-2][0][-1].kind.startswith('BUILD_TUPLE'): if node[-2][0][-1] != 'BUILD_TUPLE_0': node[-2][0].kind = 'build_tuple2' self.default(node) n_store_subscr = n_subscript = n_delete_subscr # Note: this node is only in Python 2.x # FIXME: figure out how to get this into customization # put so that we can get access via super from # the fragments routine. def n_exec_stmt(self, node): """ exec_stmt ::= expr exprlist DUP_TOP EXEC_STMT exec_stmt ::= expr exprlist EXEC_STMT """ self.write(self.indent, 'exec ') self.preorder(node[0]) if not node[1][0].isNone(): sep = ' in ' for subnode in node[1]: self.write(sep); sep = ", " self.preorder(subnode) self.println() self.prune() # stop recursing def n_ifelsestmt(self, node, preprocess=False): else_suite = node[3] n = else_suite[0] if len(n) == 1 == len(n[0]) and n[0] == '_stmts': n = n[0][0][0] elif n[0].kind in ('lastc_stmt', 'lastl_stmt'): n = n[0][0] else: if not preprocess: self.default(node) return if n.kind in ('ifstmt', 'iflaststmt', 'iflaststmtl'): node.kind = 'ifelifstmt' n.kind = 'elifstmt' elif n.kind in ('ifelsestmtr',): node.kind = 'ifelifstmt' n.kind = 'elifelsestmtr' elif n.kind in ('ifelsestmt', 'ifelsestmtc', 'ifelsestmtl'): node.kind = 'ifelifstmt' self.n_ifelsestmt(n, preprocess=True) if n == 'ifelifstmt': n.kind = 'elifelifstmt' elif n.kind in ('ifelsestmt', 'ifelsestmtc', 'ifelsestmtl'): n.kind = 'elifelsestmt' if not preprocess: self.default(node) n_ifelsestmtc = n_ifelsestmtl = n_ifelsestmt def n_ifelsestmtr(self, node): if node[2] == 'COME_FROM': return_stmts_node = node[3] node.kind = 'ifelsestmtr2' else: return_stmts_node = node[2] if len(return_stmts_node) != 2: self.default(node) if (not (return_stmts_node[0][0][0] == 'ifstmt' and return_stmts_node[0][0][0][1][0] == 'return_if_stmts') and not (return_stmts_node[0][-1][0] == 'ifstmt' and return_stmts_node[0][-1][0][1][0] == 'return_if_stmts')): self.default(node) return self.write(self.indent, 'if ') self.preorder(node[0]) self.println(':') self.indent_more() self.preorder(node[1]) self.indent_less() if_ret_at_end = False if len(return_stmts_node[0]) >= 3: if (return_stmts_node[0][-1][0] == 'ifstmt' and return_stmts_node[0][-1][0][1][0] == 'return_if_stmts'): if_ret_at_end = True past_else = False prev_stmt_is_if_ret = True for n in return_stmts_node[0]: if (n[0] == 'ifstmt' and n[0][1][0] == 'return_if_stmts'): if prev_stmt_is_if_ret: n[0].kind = 'elifstmt' prev_stmt_is_if_ret = True else: prev_stmt_is_if_ret = False if not past_else and not if_ret_at_end: self.println(self.indent, 'else:') self.indent_more() past_else = True self.preorder(n) if not past_else or if_ret_at_end: self.println(self.indent, 'else:') self.indent_more() self.preorder(return_stmts_node[1]) self.indent_less() self.prune() n_ifelsestmtr2 = n_ifelsestmtr def n_elifelsestmtr(self, node): if node[2] == 'COME_FROM': return_stmts_node = node[3] node.kind = 'elifelsestmtr2' else: return_stmts_node = node[2] if len(return_stmts_node) != 2: self.default(node) for n in return_stmts_node[0]: if not (n[0] == 'ifstmt' and n[0][1][0] == 'return_if_stmts'): self.default(node) return self.write(self.indent, 'elif ') self.preorder(node[0]) self.println(':') self.indent_more() self.preorder(node[1]) self.indent_less() for n in return_stmts_node[0]: n[0].kind = 'elifstmt' self.preorder(n) self.println(self.indent, 'else:') self.indent_more() self.preorder(return_stmts_node[1]) self.indent_less() self.prune() def n_alias(self, node): if self.version <= 2.1: if len(node) == 2: store = node[1] assert store == 'store' if store[0].pattr == node[0].pattr: self.write("import %s\n" % node[0].pattr) else: self.write("import %s as %s\n" % (node[0].pattr, store[0].pattr)) pass pass self.prune() # stop recursing store_node = node[-1][-1] assert store_node.kind.startswith('STORE_') iname = node[0].pattr # import name sname = store_node.pattr # store_name if iname and iname == sname or iname.startswith(sname + '.'): self.write(iname) else: self.write(iname, ' as ', sname) self.prune() # stop recursing def n_import_from(self, node): relative_path_index = 0 if self.version >= 2.5: if node[relative_path_index].pattr > 0: node[2].pattr = ('.' * node[relative_path_index].pattr) + node[2].pattr if self.version > 2.7: if isinstance(node[1].pattr, tuple): imports = node[1].pattr for pattr in imports: node[1].pattr = pattr self.default(node) return pass self.default(node) n_import_from_star = n_import_from def n_mkfunc(self, node): if self.version >= 3.3 or node[-2] in ('kwargs', 'no_kwargs'): # LOAD_CONST code object .. # LOAD_CONST 'x0' if >= 3.3 # MAKE_FUNCTION .. code_node = node[-3] elif node[-2] == 'expr': code_node = node[-2][0] else: # LOAD_CONST code object .. # MAKE_FUNCTION .. code_node = node[-2] func_name = code_node.attr.co_name self.write(func_name) self.indent_more() self.make_function(node, is_lambda=False, code_node=code_node) if len(self.param_stack) > 1: self.write('\n\n') else: self.write('\n\n\n') self.indent_less() self.prune() # stop recursing def make_function(self, node, is_lambda, nested=1, code_node=None, annotate=None): if self.version >= 3.0: make_function3(self, node, is_lambda, nested, code_node) else: make_function2(self, node, is_lambda, nested, code_node) def n_mklambda(self, node): self.make_function(node, is_lambda=True, code_node=node[-2]) self.prune() # stop recursing def n_list_comp(self, node): """List comprehensions""" p = self.prec self.prec = 100 if self.version >= 2.7: if self.is_pypy: self.n_list_comp_pypy27(node) return n = node[-1] elif node[-1] == 'del_stmt': if node[-2] == 'JUMP_BACK': n = node[-3] else: n = node[-2] assert n == 'list_iter' # Find the list comprehension body. It is the inner-most # node that is not list_.. . # FIXME: DRY with other use while n == 'list_iter': n = n[0] # iterate one nesting deeper if n == 'list_for': n = n[3] elif n == 'list_if': n = n[2] elif n == 'list_if_not': n = n[2] assert n == 'lc_body' self.write( '[ ') if self.version >= 2.7: expr = n[0] list_iter = node[-1] else: expr = n[1] if node[-2] == 'JUMP_BACK': list_iter = node[-3] else: list_iter = node[-2] assert expr == 'expr' assert list_iter == 'list_iter' # FIXME: use source line numbers for directing line breaks line_number = self.line_number last_line = self.f.getvalue().split("\n")[-1] l = len(last_line) indent = ' ' * (l-1) self.preorder(expr) line_number = self.indent_if_source_nl(line_number, indent) self.preorder(list_iter) l2 = self.indent_if_source_nl(line_number, indent) if l2 != line_number: self.write(' ' * (len(indent) - len(self.indent) - 1) + ']') else: self.write( ' ]') self.prec = p self.prune() # stop recursing def n_list_comp_pypy27(self, node): """List comprehensions in PYPY.""" p = self.prec self.prec = 27 if node[-1].kind == 'list_iter': n = node[-1] elif self.is_pypy and node[-1] == 'JUMP_BACK': n = node[-2] list_expr = node[1] if len(node) >= 3: store = node[3] elif self.is_pypy and n[0] == 'list_for': store = n[0][2] assert n == 'list_iter' assert store == 'store' # Find the list comprehension body. It is the inner-most # node. # FIXME: DRY with other use while n == 'list_iter': n = n[0] # iterate one nesting deeper if n == 'list_for': n = n[3] elif n == 'list_if': n = n[2] elif n == 'list_if_not': n = n[2] assert n == 'lc_body' self.write( '[ ') expr = n[0] if self.is_pypy and node[-1] == 'JUMP_BACK': list_iter = node[-2] else: list_iter = node[-1] assert expr == 'expr' assert list_iter == 'list_iter' # FIXME: use source line numbers for directing line breaks self.preorder(expr) self.preorder(list_expr) self.write( ' ]') self.prec = p self.prune() # stop recursing def comprehension_walk(self, node, iter_index, code_index=-5): p = self.prec self.prec = 27 # FIXME: clean this up if self.version >= 3.0 and node == 'dict_comp': cn = node[1] elif self.version <= 2.7 and node == 'generator_exp': if node[0] == 'LOAD_GENEXPR': cn = node[0] elif node[0] == 'load_closure': cn = node[1] elif self.version >= 3.0 and node == 'generator_exp': if node[0] == 'load_genexpr': load_genexpr = node[0] elif node[1] == 'load_genexpr': load_genexpr = node[1] cn = load_genexpr[0] elif hasattr(node[code_index], 'attr'): # Python 2.5+ (and earlier?) does this cn = node[code_index] else: if len(node[1]) > 1 and hasattr(node[1][1], 'attr'): # Python 3.3+ does this cn = node[1][1] elif hasattr(node[1][0], 'attr'): # Python 3.2 does this cn = node[1][0] else: assert False, "Can't find code for comprehension" assert iscode(cn.attr) code = Code(cn.attr, self.scanner, self.currentclass) ast = self.build_ast(code._tokens, code._customize) self.customize(code._customize) ast = ast[0][0][0] n = ast[iter_index] assert n == 'comp_iter', n # Find the comprehension body. It is the inner-most # node that is not list_.. . while n == 'comp_iter': # list_iter n = n[0] # recurse one step if n == 'comp_for': if n[0] == 'SETUP_LOOP': n = n[4] else: n = n[3] elif n == 'comp_if': n = n[2] elif n == 'comp_if_not': n = n[2] assert n == 'comp_body', n self.preorder(n[0]) self.write(' for ') self.preorder(ast[iter_index-1]) self.write(' in ') if node[2] == 'expr': iter_expr = node[2] else: iter_expr = node[-3] assert iter_expr == 'expr' self.preorder(iter_expr) self.preorder(ast[iter_index]) self.prec = p def n_generator_exp(self, node): self.write('(') if self.version > 3.2: code_index = -6 else: code_index = -5 self.comprehension_walk(node, iter_index=3, code_index=code_index) self.write(')') self.prune() def n_set_comp(self, node): self.write('{') if node[0] in ['LOAD_SETCOMP', 'LOAD_DICTCOMP']: self.comprehension_walk_newer(node, 1, 0) elif node[0].kind == 'load_closure' and self.version >= 3.0: self.setcomprehension_walk3(node, collection_index=4) else: self.comprehension_walk(node, iter_index=4) self.write('}') self.prune() n_dict_comp = n_set_comp def comprehension_walk_newer(self, node, iter_index, code_index=-5): """Non-closure-based comprehensions the way they are done in Python3 and some Python 2.7. Note: there are also other set comprehensions. """ p = self.prec self.prec = 27 code = node[code_index].attr assert iscode(code), node[code_index] code = Code(code, self.scanner, self.currentclass) ast = self.build_ast(code._tokens, code._customize) self.customize(code._customize) # skip over: sstmt, stmt, return, ret_expr # and other singleton derivations while (len(ast) == 1 or (ast in ('sstmt', 'return') and ast[-1] in ('RETURN_LAST', 'RETURN_VALUE'))): self.prec = 100 ast = ast[0] # Pick out important parts of the comprehension: # * the variable we interate over: "store" # * the results we accumulate: "n" is_30_dict_comp = False store = None n = ast[iter_index] if ast in ('set_comp_func', 'dict_comp_func', 'list_comp', 'set_comp_func_header'): for k in ast: if k == 'comp_iter': n = k elif k == 'store': store = k pass pass pass elif ast in ('dict_comp', 'set_comp'): assert self.version == 3.0 for k in ast: if k in ('dict_comp_header', 'set_comp_header'): n = k elif k == 'store': store = k elif k == 'dict_comp_iter': is_30_dict_comp = True n = (k[3], k[1]) pass elif k == 'comp_iter': n = k[1] pass pass else: assert n == 'list_iter', n # FIXME: I'm not totally sure this is right. # Find the list comprehension body. It is the inner-most # node that is not list_.. . if_node = None comp_for = None comp_store = None if n == 'comp_iter': comp_for = n comp_store = ast[3] have_not = False while n in ('list_iter', 'comp_iter'): # iterate one nesting deeper if self.version == 3.0 and len(n) == 3: assert n[0] == 'expr' and n[1] == 'expr' n = n[1] else: n = n[0] if n in ('list_for', 'comp_for'): if n[2] == 'store': store = n[2] n = n[3] elif n in ('list_if', 'list_if_not', 'comp_if', 'comp_if_not'): have_not = n in ('list_if_not', 'comp_if_not') if_node = n[0] if n[1] == 'store': store = n[1] n = n[2] pass pass # Python 2.7+ starts including set_comp_body # Python 3.5+ starts including set_comp_func # Python 3.0 is yet another snowflake if self.version != 3.0: assert n.kind in ('lc_body', 'comp_body', 'set_comp_func', 'set_comp_body'), ast assert store, "Couldn't find store in list/set comprehension" # A problem created with later Python code generation is that there # is a lamda set up with a dummy argument name that is then called # So we can't just translate that as is but need to replace the # dummy name. Below we are picking out the variable name as seen # in the code. And trying to generate code for the other parts # that don't have the dummy argument name in it. # Another approach might be to be able to pass in the source name # for the dummy argument. if is_30_dict_comp: self.preorder(n[0]) self.write(': ') self.preorder(n[1]) else: self.preorder(n[0]) self.write(' for ') if comp_store: self.preorder(comp_store) else: self.preorder(store) # FIXME this is all merely approximate self.write(' in ') self.preorder(node[-3]) if ast == 'list_comp' and self.version != 3.0: list_iter = ast[1] assert list_iter == 'list_iter' if list_iter == 'list_for': self.preorder(list_iter[3]) self.prec = p return pass if comp_store: self.preorder(comp_for) elif if_node: self.write(' if ') if have_not: self.write('not ') self.preorder(if_node) pass self.prec = p def listcomprehension_walk2(self, node): """List comprehensions the way they are done in Python 2 and sometimes in Python 3. They're more other comprehensions, e.g. set comprehensions See if we can combine code. """ p = self.prec self.prec = 27 code = Code(node[1].attr, self.scanner, self.currentclass) ast = self.build_ast(code._tokens, code._customize) self.customize(code._customize) # skip over: sstmt, stmt, return, ret_expr # and other singleton derivations while (len(ast) == 1 or (ast in ('sstmt', 'return') and ast[-1] in ('RETURN_LAST', 'RETURN_VALUE'))): self.prec = 100 ast = ast[0] n = ast[1] # collection = node[-3] collections = [node[-3]] list_ifs = [] if self.version == 3.0 and n != 'list_iter': # FIXME 3.0 is a snowflake here. We need # special code for this. Not sure if this is totally # correct. stores = [ast[3]] assert ast[4] == 'comp_iter' n = ast[4] # Find the list comprehension body. It is the inner-most # node that is not comp_.. . while n == 'comp_iter': if n[0] == 'comp_for': n = n[0] stores.append(n[2]) n = n[3] elif n[0] in ('comp_if', 'comp_if_not'): n = n[0] # FIXME: just a guess if n[0].kind == 'expr': list_ifs.append(n) else: list_ifs.append([1]) n = n[2] pass else: break pass # Skip over n[0] which is something like: _[1] self.preorder(n[1]) else: assert n == 'list_iter' stores = [] # Find the list comprehension body. It is the inner-most # node that is not list_.. . while n == 'list_iter': n = n[0] # recurse one step if n == 'list_for': stores.append(n[2]) n = n[3] if self.version >= 3.6 and n[0] == 'list_for': # Dog-paddle down largely singleton reductions # to find the collection (expr) c = n[0][0] if c == 'expr': c = c[0] # FIXME: grammar is wonky here? Is this really an attribute? if c == 'attribute': c = c[0] collections.append(c) pass elif n in ('list_if', 'list_if_not'): # FIXME: just a guess if n[0].kind == 'expr': list_ifs.append(n) else: list_ifs.append([1]) n = n[2] pass pass assert n == 'lc_body', ast self.preorder(n[0]) # FIXME: add indentation around "for"'s and "in"'s if self.version < 3.6: self.write(' for ') self.preorder(stores[0]) self.write(' in ') self.preorder(collections[0]) if list_ifs: self.preorder(list_ifs[0]) pass else: for i, store in enumerate(stores): self.write(' for ') self.preorder(store) self.write(' in ') self.preorder(collections[i]) if i < len(list_ifs): self.preorder(list_ifs[i]) pass pass self.prec = p def n_listcomp(self, node): self.write('[') if node[0].kind == 'load_closure': self.listcomprehension_walk2(node) else: self.comprehension_walk_newer(node, 1, 0) self.write(']') self.prune() def setcomprehension_walk3(self, node, collection_index): """Set comprehensions the way they are done in Python3. They're more other comprehensions, e.g. set comprehensions See if we can combine code. """ p = self.prec self.prec = 27 code = Code(node[1].attr, self.scanner, self.currentclass) ast = self.build_ast(code._tokens, code._customize) self.customize(code._customize) ast = ast[0][0][0] store = ast[3] collection = node[collection_index] n = ast[4] list_if = None assert n == 'comp_iter' # find innermost node while n == 'comp_iter': n = n[0] # recurse one step # FIXME: adjust for set comprehension if n == 'list_for': store = n[2] n = n[3] elif n in ('list_if', 'list_if_not', 'comp_if', 'comp_if_not'): # FIXME: just a guess if n[0].kind == 'expr': list_if = n else: list_if = n[1] n = n[2] pass pass assert n == 'comp_body', ast self.preorder(n[0]) self.write(' for ') self.preorder(store) self.write(' in ') self.preorder(collection) if list_if: self.preorder(list_if) self.prec = p def n_classdef(self, node): if self.version >= 3.0: self.n_classdef3(node) # class definition ('class X(A,B,C):') cclass = self.currentclass # Pick out various needed bits of information # * class_name - the name of the class # * subclass_info - the parameters to the class e.g. # class Foo(bar, baz) # ----------- # * subclass_code - the code for the subclass body if node == 'classdefdeco2': build_class = node else: build_class = node[0] build_list = build_class[1][0] if hasattr(build_class[-3][0], 'attr'): subclass_code = build_class[-3][0].attr class_name = build_class[0].pattr elif (build_class[-3] == 'mkfunc' and node == 'classdefdeco2' and build_class[-3][0] == 'load_closure'): subclass_code = build_class[-3][1].attr class_name = build_class[-3][0][0].pattr elif hasattr(node[0][0], 'pattr'): subclass_code = build_class[-3][1].attr class_name = node[0][0].pattr else: raise 'Internal Error n_classdef: cannot find class name' if (node == 'classdefdeco2'): self.write('\n') else: self.write('\n\n') self.currentclass = str(class_name) self.write(self.indent, 'class ', self.currentclass) self.print_super_classes(build_list) self.println(':') # class body self.indent_more() self.build_class(subclass_code) self.indent_less() self.currentclass = cclass if len(self.param_stack) > 1: self.write('\n\n') else: self.write('\n\n\n') self.prune() n_classdefdeco2 = n_classdef def print_super_classes(self, node): if not (node == 'tuple'): return n_subclasses = len(node[:-1]) if n_subclasses > 0 or self.version > 2.4: # Not an old-style pre-2.2 class self.write('(') line_separator = ', ' sep = '' for elem in node[:-1]: value = self.traverse(elem) self.write(sep, value) sep = line_separator if n_subclasses > 0 or self.version > 2.4: # Not an old-style pre-2.2 class self.write(')') def print_super_classes3(self, node): n = len(node) - 1 if node.kind != 'expr': if node == 'kwarg': self.write('(') self.template_engine(('%[0]{pattr}=%c', 1), node) self.write(')') return kwargs = None assert node[n].kind.startswith('CALL_FUNCTION') if node[n].kind.startswith('CALL_FUNCTION_KW'): # 3.6+ starts does this kwargs = node[n-1].attr assert isinstance(kwargs, tuple) i = n - (len(kwargs)+1) j = 1 + n - node[n].attr else: start = n-2 for i in range(start, 0, -1): if not node[i].kind in ['expr', 'call', 'LOAD_CLASSNAME']: break pass if i == start: return i += 2 line_separator = ', ' sep = '' self.write('(') if kwargs: # Last arg is tuple of keyword values: omit l = n - 1 else: l = n if kwargs: # 3.6+ does this while j < i: self.write(sep) value = self.traverse(node[j]) self.write("%s" % value) sep = line_separator j += 1 j = 0 while i < l: self.write(sep) value = self.traverse(node[i]) self.write("%s=%s" % (kwargs[j], value)) sep = line_separator j += 1 i += 1 else: while i < l: value = self.traverse(node[i]) i += 1 self.write(sep, value) sep = line_separator pass pass else: if self.version >= 3.6 and node[0] == 'LOAD_CONST': return value = self.traverse(node[0]) self.write('(') self.write(value) pass self.write(')') def n_dict(self, node): """ prettyprint a dict 'dict' is something like k = {'a': 1, 'b': 42}" We will source-code use line breaks to guide us when to break. """ p = self.prec self.prec = 100 self.indent_more(INDENT_PER_LEVEL) sep = INDENT_PER_LEVEL[:-1] if node[0] != 'dict_entry': self.write('{') line_number = self.line_number if self.version >= 3.0 and not self.is_pypy: if node[0].kind.startswith('kvlist'): # Python 3.5+ style key/value list in dict kv_node = node[0] l = list(kv_node) length = len(l) if kv_node[-1].kind.startswith("BUILD_MAP"): length -= 1 i = 0 # Respect line breaks from source while i < length: self.write(sep) name = self.traverse(l[i], indent='') if i > 0: line_number = self.indent_if_source_nl(line_number, self.indent + INDENT_PER_LEVEL[:-1]) line_number = self.line_number self.write(name, ': ') value = self.traverse(l[i+1], indent=self.indent+(len(name)+2)*' ') self.write(value) sep = ", " if line_number != self.line_number: sep += "\n" + self.indent + INDENT_PER_LEVEL[:-1] line_number = self.line_number i += 2 pass pass elif len(node) > 1 and node[1].kind.startswith('kvlist'): # Python 3.0..3.4 style key/value list in dict kv_node = node[1] l = list(kv_node) if len(l) > 0 and l[0].kind == 'kv3': # Python 3.2 does this kv_node = node[1][0] l = list(kv_node) i = 0 while i < len(l): self.write(sep) name = self.traverse(l[i+1], indent='') if i > 0: line_number = self.indent_if_source_nl(line_number, self.indent + INDENT_PER_LEVEL[:-1]) pass line_number = self.line_number self.write(name, ': ') value = self.traverse(l[i], indent=self.indent+(len(name)+2)*' ') self.write(value) sep = ", " if line_number != self.line_number: sep += "\n" + self.indent + INDENT_PER_LEVEL[:-1] line_number = self.line_number else: sep += " " i += 3 pass pass elif node[-1].kind.startswith('BUILD_CONST_KEY_MAP'): # Python 3.6+ style const map keys = node[-2].pattr values = node[:-2] # FIXME: Line numbers? for key, value in zip(keys, values): self.write(sep) self.write(repr(key)) line_number = self.line_number self.write(':') self.write(self.traverse(value[0])) sep = ", " if line_number != self.line_number: sep += "\n" + self.indent + INDENT_PER_LEVEL[:-1] line_number = self.line_number else: sep += " " pass pass if sep.startswith(",\n"): self.write(sep[1:]) pass elif node[0].kind.startswith('dict_entry'): assert self.version >= 3.5 template = ("%C", (0, len(node[0]), ", **")) self.template_engine(template, node[0]) sep = '' elif (node[-1].kind.startswith('BUILD_MAP_UNPACK') or node[-1].kind.startswith('dict_entry')): assert self.version >= 3.5 # FIXME: I think we can intermingle dict_comp's with other # dictionary kinds of things. The most common though is # a sequence of dict_comp's kwargs = node[-1].attr template = ("**%C", (0, kwargs, ", **")) self.template_engine(template, node) sep = '' pass else: # Python 2 style kvlist. Find beginning of kvlist. if node[0].kind.startswith("BUILD_MAP"): if len(node) > 1 and node[1].kind in ('kvlist', 'kvlist_n'): kv_node = node[1] else: kv_node = node[1:] else: assert node[-1].kind.startswith('kvlist') kv_node = node[-1] first_time = True for kv in kv_node: assert kv in ('kv', 'kv2', 'kv3') # kv ::= DUP_TOP expr ROT_TWO expr STORE_SUBSCR # kv2 ::= DUP_TOP expr expr ROT_THREE STORE_SUBSCR # kv3 ::= expr expr STORE_MAP # FIXME: DRY this and the above indent = self.indent + " " if kv == 'kv': self.write(sep) name = self.traverse(kv[-2], indent='') if first_time: line_number = self.indent_if_source_nl(line_number, indent) first_time = False pass line_number = self.line_number self.write(name, ': ') value = self.traverse(kv[1], indent=self.indent+(len(name)+2)*' ') elif kv == 'kv2': self.write(sep) name = self.traverse(kv[1], indent='') if first_time: line_number = self.indent_if_source_nl(line_number, indent) first_time = False pass line_number = self.line_number self.write(name, ': ') value = self.traverse(kv[-3], indent=self.indent+(len(name)+2)*' ') elif kv == 'kv3': self.write(sep) name = self.traverse(kv[-2], indent='') if first_time: line_number = self.indent_if_source_nl(line_number, indent) first_time = False pass line_number = self.line_number self.write(name, ': ') line_number = self.line_number value = self.traverse(kv[0], indent=self.indent+(len(name)+2)*' ') pass self.write(value) sep = ", " if line_number != self.line_number: sep += "\n" + self.indent + " " line_number = self.line_number pass pass pass if sep.startswith(",\n"): self.write(sep[1:]) if node[0] != 'dict_entry': self.write('}') self.indent_less(INDENT_PER_LEVEL) self.prec = p self.prune() def n_list(self, node): """ prettyprint a list or tuple """ p = self.prec self.prec = 100 lastnode = node.pop() lastnodetype = lastnode.kind # If this build list is inside a CALL_FUNCTION_VAR, # then the first * has already been printed. # Until I have a better way to check for CALL_FUNCTION_VAR, # will assume that if the text ends in *. last_was_star = self.f.getvalue().endswith('*') if lastnodetype.endswith('UNPACK'): # FIXME: need to handle range of BUILD_LIST_UNPACK have_star = True # endchar = '' else: have_star = False if lastnodetype.startswith('BUILD_LIST'): self.write('['); endchar = ']' elif lastnodetype.startswith('BUILD_TUPLE'): # Tuples can appear places that can NOT # have parenthesis around them, like array # subscripts. We check for that by seeing # if a tuple item is some sort of slice. no_parens = False for n in node: if n == 'expr' and n[0].kind.startswith('build_slice'): no_parens = True break pass if no_parens: endchar = '' else: self.write('('); endchar = ')' pass elif lastnodetype.startswith('BUILD_SET'): self.write('{'); endchar = '}' elif lastnodetype.startswith('BUILD_MAP_UNPACK'): self.write('{*'); endchar = '}' elif lastnodetype.startswith('ROT_TWO'): self.write('('); endchar = ')' else: raise TypeError('Internal Error: n_build_list expects list, tuple, set, or unpack') flat_elems = flatten_list(node) self.indent_more(INDENT_PER_LEVEL) sep = '' for elem in flat_elems: if elem in ('ROT_THREE', 'EXTENDED_ARG'): continue assert elem == 'expr' line_number = self.line_number value = self.traverse(elem) if line_number != self.line_number: sep += '\n' + self.indent + INDENT_PER_LEVEL[:-1] else: if sep != '': sep += ' ' if not last_was_star: if have_star: sep += '*' pass pass else: last_was_star = False self.write(sep, value) sep = ',' if lastnode.attr == 1 and lastnodetype.startswith('BUILD_TUPLE'): self.write(',') self.write(endchar) self.indent_less(INDENT_PER_LEVEL) self.prec = p self.prune() return n_set = n_tuple = n_build_set = n_list def n_unpack(self, node): if node[0].kind.startswith('UNPACK_EX'): # Python 3+ before_count, after_count = node[0].attr for i in range(before_count+1): self.preorder(node[i]) if i != 0: self.write(', ') self.write('*') for i in range(1, after_count+2): self.preorder(node[before_count+i]) if i != after_count + 1: self.write(', ') self.prune() return for n in node[1:]: if n[0].kind == 'unpack': n[0].kind = 'unpack_w_parens' self.default(node) n_unpack_w_parens = n_unpack def n_attribute(self, node): if (node[0] == 'LOAD_CONST' or node[0] == 'expr' and node[0][0] == 'LOAD_CONST'): # FIXME: I didn't record which constants parenthesis is # necessary. However, I suspect that we could further # refine this by looking at operator precedence and # eval'ing the constant value (pattr) and comparing with # the type of the constant. node.kind = 'attribute_w_parens' self.default(node) def n_assign(self, node): # A horrible hack for Python 3.0 .. 3.2 if 3.0 <= self.version <= 3.2 and len(node) == 2: if (node[0][0] == 'LOAD_FAST' and node[0][0].pattr == '__locals__' and node[1][0].kind == 'STORE_LOCALS'): self.prune() self.default(node) def n_assign2(self, node): for n in node[-2:]: if n[0] == 'unpack': n[0].kind = 'unpack_w_parens' self.default(node) def n_assign3(self, node): for n in node[-3:]: if n[0] == 'unpack': n[0].kind = 'unpack_w_parens' self.default(node) def n_except_cond2(self, node): if node[-2][0] == 'unpack': node[-2][0].kind = 'unpack_w_parens' self.default(node) # except_cond3 is only in Python <= 2.6 n_except_cond3 = n_except_cond2 def template_engine(self, entry, startnode): """The format template interpetation engine. See the comment at the beginning of this module for the how we interpret format specifications such as %c, %C, and so on. """ # print("-----") # print(startnode) # print(entry[0]) # print('======') fmt = entry[0] arg = 1 i = 0 m = escape.search(fmt) while m: i = m.end() self.write(m.group('prefix')) typ = m.group('type') or '{' node = startnode if m.group('child'): node = node[int(m.group('child'))] if typ == '%': self.write('%') elif typ == '+': self.line_number += 1 self.indent_more() elif typ == '-': self.line_number += 1 self.indent_less() elif typ == '|': self.line_number += 1 self.write(self.indent) # Used mostly on the LHS of an assignment # BUILD_TUPLE_n is pretty printed and may take care of other uses. elif typ == ',': if (node.kind in ('unpack', 'unpack_w_parens') and node[0].attr == 1): self.write(',') elif typ == 'c': index = entry[arg] if isinstance(index, tuple): assert node[index[0]] == index[1], ( "at %s[%d], expected '%s' node; got '%s'" % ( node.kind, arg, index[1], node[index[0]].kind) ) index = index[0] assert isinstance(index, int), ( "at %s[%d], %s should be int or tuple" % ( node.kind, arg, type(index))) self.preorder(node[index]) arg += 1 elif typ == 'p': p = self.prec (index, self.prec) = entry[arg] self.preorder(node[index]) self.prec = p arg += 1 elif typ == 'C': low, high, sep = entry[arg] remaining = len(node[low:high]) for subnode in node[low:high]: self.preorder(subnode) remaining -= 1 if remaining > 0: self.write(sep) pass pass arg += 1 elif typ == 'D': low, high, sep = entry[arg] remaining = len(node[low:high]) for subnode in node[low:high]: remaining -= 1 if len(subnode) > 0: self.preorder(subnode) if remaining > 0: self.write(sep) pass pass pass arg += 1 elif typ == 'x': # This code is only used in fragments assert isinstance(entry[arg], tuple) arg += 1 elif typ == 'P': p = self.prec low, high, sep, self.prec = entry[arg] remaining = len(node[low:high]) # remaining = len(node[low:high]) for subnode in node[low:high]: self.preorder(subnode) remaining -= 1 if remaining > 0: self.write(sep) self.prec = p arg += 1 elif typ == '{': d = node.__dict__ expr = m.group('expr') # Line mapping stuff if (hasattr(node, 'linestart') and node.linestart and hasattr(node, 'current_line_number')): self.source_linemap[self.current_line_number] = node.linestart try: self.write(eval(expr, d, d)) except: raise m = escape.search(fmt, i) self.write(fmt[i:]) def default(self, node): mapping = self._get_mapping(node) table = mapping[0] key = node for i in mapping[1:]: key = key[i] pass if key.kind in table: self.template_engine(table[key.kind], node) self.prune() def customize(self, customize): """ Special handling for opcodes, such as those that take a variable number of arguments -- we add a new entry for each in TABLE_R. """ for k, v in list(customize.items()): if k in TABLE_R: continue op = k[ :k.rfind('_') ] if k.startswith('CALL_METHOD'): # This happens in PyPy only TABLE_R[k] = ('%c(%P)', 0, (1, -1, ', ', 100)) elif self.version >= 3.6 and k.startswith('CALL_FUNCTION_KW'): TABLE_R[k] = ('%c(%P)', 0, (1, -1, ', ', 100)) elif op == 'CALL_FUNCTION': TABLE_R[k] = ('%c(%P)', 0, (1, -1, ', ', 100)) elif op in ('CALL_FUNCTION_VAR', 'CALL_FUNCTION_VAR_KW', 'CALL_FUNCTION_KW'): # FIXME: handle everything in customize. # Right now, some of this is here, and some in that. if v == 0: str = '%c(%C' # '%C' is a dummy here ... p2 = (0, 0, None) # .. because of the None in this else: str = '%c(%C, ' p2 = (1, -2, ', ') if op == 'CALL_FUNCTION_VAR': # Python 3.5 only puts optional args (the VAR part) # lowest down the stack if self.version == 3.5: if str == '%c(%C, ': entry = ('%c(*%C, %c)', 0, p2, -2) elif str == '%c(%C': entry = ('%c(*%C)', 0, (1, 100, '')) elif self.version == 3.4: # CALL_FUNCTION_VAR's top element of the stack contains # the variable argument list if v == 0: str = '%c(*%c)' entry = (str, 0, -2) else: str = '%c(%C, *%c)' entry = (str, 0, p2, -2) else: str += '*%c)' entry = (str, 0, p2, -2) elif op == 'CALL_FUNCTION_KW': str += '**%c)' entry = (str, 0, p2, -2) elif op == 'CALL_FUNCTION_VAR_KW': str += '*%c, **%c)' # Python 3.5 only puts optional args (the VAR part) # lowest down the stack na = (v & 0xff) # positional parameters if self.version == 3.5 and na == 0: if p2[2]: p2 = (2, -2, ', ') entry = (str, 0, p2, 1, -2) else: if p2[2]: p2 = (1, -3, ', ') entry = (str, 0, p2, -3, -2) pass else: assert False, "Unhandled CALL_FUNCTION %s" % op TABLE_R[k] = entry pass # handled by n_dict: # if op == 'BUILD_SLICE': TABLE_R[k] = ('%C' , (0,-1,':')) # handled by n_list: # if op == 'BUILD_LIST': TABLE_R[k] = ('[%C]' , (0,-1,', ')) # elif op == 'BUILD_TUPLE': TABLE_R[k] = ('(%C%,)', (0,-1,', ')) pass return def get_tuple_parameter(self, ast, name): """ If the name of the formal parameter starts with dot, it's a tuple parameter, like this: # def MyFunc(xx, (a,b,c), yy): # print a, b*2, c*42 In byte-code, the whole tuple is assigned to parameter '.1' and then the tuple gets unpacked to 'a', 'b' and 'c'. Since identifiers starting with a dot are illegal in Python, we can search for the byte-code equivalent to '(a,b,c) = .1' """ assert ast == 'stmts' for i in range(len(ast)): # search for an assign-statement assert ast[i][0] == 'stmt' node = ast[i][0][0] if (node == 'assign' and node[0] == ASSIGN_TUPLE_PARAM(name)): # okay, this assigns '.n' to something del ast[i] # walk lhs; this # returns a tuple of identifiers as used # within the function definition assert node[1] == 'store' # if lhs is not a UNPACK_TUPLE (or equiv.), # add parenteses to make this a tuple # if node[1][0] not in ('unpack', 'unpack_list'): return '(' + self.traverse(node[1]) + ')' # return self.traverse(node[1]) raise Exception("Can't find tuple parameter " + name) def build_class(self, code): """Dump class definition, doc string and class body.""" assert iscode(code) self.classes.append(self.currentclass) code = Code(code, self.scanner, self.currentclass) indent = self.indent # self.println(indent, '#flags:\t', int(code.co_flags)) ast = self.build_ast(code._tokens, code._customize) code._tokens = None # save memory assert ast == 'stmts' first_stmt = ast[0][0] if 3.0 <= self.version <= 3.3: try: if first_stmt[0] == 'store_locals': if self.hide_internal: del ast[0] first_stmt = ast[0][0] except: pass try: if first_stmt == NAME_MODULE: if self.hide_internal: del ast[0] first_stmt = ast[0][0] pass except: pass have_qualname = False if self.version < 3.0: # Should we ditch this in favor of the "else" case? qualname = '.'.join(self.classes) QUAL_NAME = SyntaxTree('stmt', [ SyntaxTree('assign', [ SyntaxTree('expr', [Token('LOAD_CONST', pattr=qualname)]), SyntaxTree('store', [ Token('STORE_NAME', pattr='__qualname__')]) ])]) have_qualname = (ast[0][0] == QUAL_NAME) else: # Python 3.4+ has constants like 'cmp_to_key..K' # which are not simple classes like the < 3 case. try: if (first_stmt[0] == 'assign' and first_stmt[0][0][0] == 'LOAD_CONST' and first_stmt[0][1] == 'store' and first_stmt[0][1][0] == Token('STORE_NAME', pattr='__qualname__')): have_qualname = True except: pass if have_qualname: if self.hide_internal: del ast[0] pass # if docstring exists, dump it if (code.co_consts and code.co_consts[0] is not None and len(ast) > 0): do_doc = False if is_docstring(ast[0]): i = 0 do_doc = True elif (len(ast) > 1 and is_docstring(ast[1])): i = 1 do_doc = True if do_doc and self.hide_internal: try: docstring = ast[i][0][0][0][0].pattr except: docstring = code.co_consts[0] if print_docstring(self, indent, docstring): self.println() del ast[i] # the function defining a class normally returns locals(); we # don't want this to show up in the source, thus remove the node if len(ast) > 0 and ast[-1][0] == RETURN_LOCALS: if self.hide_internal: del ast[-1] # remove last node # else: # print ast[-1][-1] globals, nonlocals = find_globals_and_nonlocals(ast, set(), set(), code, self.version) # Add "global" declaration statements at the top # of the function for g in sorted(globals): self.println(indent, 'global ', g) for nl in sorted(nonlocals): self.println(indent, 'nonlocal ', nl) old_name = self.name self.gen_source(ast, code.co_name, code._customize) self.name = old_name code._tokens = None; code._customize = None # save memory self.classes.pop(-1) def gen_source(self, ast, name, customize, is_lambda=False, returnNone=False): """convert SyntaxTree to Python source code""" rn = self.return_none self.return_none = returnNone old_name = self.name self.name = name # if code would be empty, append 'pass' if len(ast) == 0: self.println(self.indent, 'pass') else: self.customize(customize) if is_lambda: self.write(self.traverse(ast, is_lambda=is_lambda)) else: self.text = self.traverse(ast, is_lambda=is_lambda) self.println(self.text) self.name = old_name self.return_none = rn def build_ast(self, tokens, customize, is_lambda=False, noneInNames=False, isTopLevel=False): # FIXME: DRY with fragments.py # assert isinstance(tokens[0], Token) if is_lambda: for t in tokens: if t.kind == 'RETURN_END_IF': t.kind = 'RETURN_END_IF_LAMBDA' elif t.kind == 'RETURN_VALUE': t.kind = 'RETURN_VALUE_LAMBDA' tokens.append(Token('LAMBDA_MARKER')) try: # FIXME: have p.insts update in a better way # modularity is broken here p_insts = self.p.insts self.p.insts = self.scanner.insts ast = python_parser.parse(self.p, tokens, customize) self.p.insts = p_insts except (python_parser.ParserError, AssertionError) as e: raise ParserError(e, tokens) maybe_show_tree(self, ast) return ast # The bytecode for the end of the main routine has a # "return None". However you can't issue a "return" statement in # main. So as the old cigarette slogan goes: I'd rather switch (the token stream) # than fight (with the grammar to not emit "return None"). if self.hide_internal: if len(tokens) >= 2 and not noneInNames: if tokens[-1].kind in ('RETURN_VALUE', 'RETURN_VALUE_LAMBDA'): # Python 3.4's classes can add a "return None" which is # invalid syntax. if tokens[-2].kind == 'LOAD_CONST': if isTopLevel or tokens[-2].pattr is None: del tokens[-2:] else: tokens.append(Token('RETURN_LAST')) else: tokens.append(Token('RETURN_LAST')) if len(tokens) == 0: return PASS # Build a parse tree from a tokenized and massaged disassembly. try: # FIXME: have p.insts update in a better way # modularity is broken here p_insts = self.p.insts self.p.insts = self.scanner.insts ast = python_parser.parse(self.p, tokens, customize) self.p.insts = p_insts except (python_parser.ParserError, AssertionError) as e: raise ParserError(e, tokens) maybe_show_tree(self, ast) checker(ast, False, self.ast_errors) return ast @classmethod def _get_mapping(cls, node): return MAP.get(node, MAP_DIRECT) # DEFAULT_DEBUG_OPTS = { 'asm': False, 'tree': False, 'grammar': False } # This interface is deprecated. Use simpler code_deparse. def deparse_code(version, co, out=sys.stdout, showasm=None, showast=False, showgrammar=False, code_objects={}, compile_mode='exec', is_pypy=IS_PYPY, walker=SourceWalker): debug_opts = { 'asm': showasm, 'ast': showast, 'grammar': showgrammar } return code_deparse(co, out, version=version, debug_opts=debug_opts, code_objects=code_objects, compile_mode=compile_mode, is_pypy=is_pypy, walker=walker) def code_deparse(co, out=sys.stdout, version=None, debug_opts=DEFAULT_DEBUG_OPTS, code_objects={}, compile_mode='exec', is_pypy=IS_PYPY, walker=SourceWalker): """ ingests and deparses a given code block 'co'. If version is None, we will use the current Python interpreter version. """ assert iscode(co) if version is None: version = float(sys.version[0:3]) # store final output stream for case of error scanner = get_scanner(version, is_pypy=is_pypy) tokens, customize = scanner.ingest(co, code_objects=code_objects, show_asm=debug_opts['asm']) debug_parser = dict(PARSER_DEFAULT_DEBUG) if debug_opts.get('grammar', None): debug_parser['reduce'] = debug_opts['grammar'] debug_parser['errorstack'] = 'full' # Build Syntax Tree from disassembly. linestarts = dict(scanner.opc.findlinestarts(co)) deparsed = walker(version, out, scanner, showast=debug_opts.get('ast', None), debug_parser=debug_parser, compile_mode=compile_mode, is_pypy=is_pypy, linestarts=linestarts) isTopLevel = co.co_name == '' deparsed.ast = deparsed.build_ast(tokens, customize, isTopLevel=isTopLevel) #### XXX workaround for profiling if deparsed.ast is None: return None assert deparsed.ast == 'stmts', 'Should have parsed grammar start' # save memory del tokens deparsed.mod_globs, nonlocals = find_globals_and_nonlocals(deparsed.ast, set(), set(), co, version) assert not nonlocals # convert leading '__doc__ = "..." into doc string try: if deparsed.ast[0][0] == ASSIGN_DOC_STRING(co.co_consts[0]): print_docstring(deparsed, '', co.co_consts[0]) del deparsed.ast[0] if deparsed.ast[-1] == RETURN_NONE: deparsed.ast.pop() # remove last node # todo: if empty, add 'pass' except: pass deparsed.FUTURE_UNICODE_LITERALS = ( COMPILER_FLAG_BIT['FUTURE_UNICODE_LITERALS'] & co.co_flags != 0) # What we've been waiting for: Generate source from Syntax Tree! deparsed.gen_source(deparsed.ast, co.co_name, customize) for g in sorted(deparsed.mod_globs): deparsed.write('# global %s ## Warning: Unused global\n' % g) if deparsed.ast_errors: deparsed.write("# NOTE: have internal decompilation grammar errors.\n") deparsed.write("# Use -t option to show full context.") for err in deparsed.ast_errors: deparsed.write(err) raise SourceWalkerError("Deparsing hit an internal grammar-rule bug") if deparsed.ERROR: raise SourceWalkerError("Deparsing stopped due to parse error") return deparsed def deparse_code2str(code, out=sys.stdout, version=None, debug_opts=DEFAULT_DEBUG_OPTS, code_objects={}, compile_mode='exec', is_pypy=IS_PYPY, walker=SourceWalker): """Return the deparsed text for a Python code object. `out` is where any intermediate output for assembly or tree output will be sent. """ return deparse_code(version, code, out, showasm=debug_opts.get('asm', None), showast=debug_opts.get('tree', None), showgrammar=debug_opts.get('grammar', None), code_objects=code_objects, compile_mode=compile_mode, is_pypy=is_pypy, walker=walker).text if __name__ == '__main__': def deparse_test(co): "This is a docstring" s = deparse_code2str(co, debug_opts={'asm':'after', 'tree':True}) # s = deparse_code2str(co, showasm=None, showast=False, # showgrammar=True) print(s) return deparse_test(deparse_test.__code__)