Files
python-uncompyle6/uncompyle6/parsers/parse25.py
2016-12-18 00:56:07 -05:00

69 lines
2.4 KiB
Python

# Copyright (c) 2016 Rocky Bernstein
"""
spark grammar differences over Python2.6 for Python 2.5.
"""
from uncompyle6.parser import PythonParserSingle
from spark_parser import DEFAULT_DEBUG as PARSER_DEFAULT_DEBUG
from uncompyle6.parsers.parse26 import Python26Parser
class Python25Parser(Python26Parser):
def __init__(self, debug_parser=PARSER_DEFAULT_DEBUG):
super(Python25Parser, self).__init__(debug_parser)
self.customized = {}
def p_misc25(self, args):
"""
# If "return_if_stmt" is in a loop, a JUMP_BACK can be emitted. In 2.6 the
# JUMP_BACK doesn't appear
return_if_stmt ::= ret_expr RETURN_END_IF JUMP_BACK
# Python 2.6 uses ROT_TWO instead of the STORE_xxx
setupwithas ::= DUP_TOP LOAD_ATTR store LOAD_ATTR CALL_FUNCTION_0
setup_finally
store ::= STORE_FAST
store ::= STORE_NAME
# Python 2.6 omits ths LOAD_FAST DELETE_FAST below
withasstmt ::= expr setupwithas designator suite_stmts_opt
POP_BLOCK LOAD_CONST COME_FROM
with_cleanup
with_cleanup ::= LOAD_FAST DELETE_FAST WITH_CLEANUP END_FINALLY
with_cleanup ::= LOAD_NAME DELETE_NAME WITH_CLEANUP END_FINALLY
"""
def add_custom_rules(self, tokens, customize):
super(Python25Parser, self).add_custom_rules(tokens, customize)
if self.version == 2.5:
self.check_reduce['tryelsestmt'] = 'tokens'
def reduce_is_invalid(self, rule, ast, tokens, first, last):
super(Python25Parser, self).reduce_is_invalid(rule, ast, tokens, first, last)
lhs = rule[0]
if lhs in ('tryelsestmt', ):
# The end of the else part of try/else come_from has to come
# from an END_FINALLY statement
if tokens[last-1].type.startswith('COME_FROM'):
end_finally_offset = int(tokens[last-1].pattr)
current = first
while current < last:
offset = tokens[current].offset
if offset == end_finally_offset:
return tokens[current].type != 'END_FINALLY'
current += 1
return False
class Python25ParserSingle(Python26Parser, PythonParserSingle):
pass
if __name__ == '__main__':
# Check grammar
p = Python25Parser()
p.checkGrammar()