Fix if return boundary in 3.6+

Fixes #209

__pkginfo__.py

@@ -57,7 +57,7 @@ entry_points       = {
     ]}
 ftp_url            = None
 install_requires   = ['spark-parser >= 1.8.7, < 1.9.0',
-                      'xdis >= 3.8.9, < 3.9.0']
+                      'xdis >= 3.8.10, < 3.9.0']
 
 license            = 'GPL3'
 mailing_list       = 'python-debugger@googlegroups.com'

test/simple_source/bug36/00_return_return_bug.py

@@ -0,0 +1,10 @@
+# Bug in 3.6 and above.
+#Not detecting 2nd return is outside of
+# if/then. Fix was to ensure COME_FROM
+def return_return_bug(foo):
+    if foo =='say_hello':
+        return "hello"
+    return "world"
+
+assert return_return_bug('say_hello') == 'hello'
+assert return_return_bug('world') == 'world'

tox.ini

@@ -3,7 +3,7 @@
 [flake8]
 exclude = .tox,./build,./trepan/processor/command/tmp
 filename = *.py
-ignore = C901,E113,E121,E122,E123,E124,E125,E126,E127,E128,E129,E201,E202,E203,E221,E222,E225,E226,E241,E242,E251,E261,E271,E272,E302,E401,E501,F401,E701,E702
+ignore = C901,E113,E121,E122,E123,E124,E125,E126,E127,E128,E129,E201,E202,E203,E221,E222,E225,E226,E241,E242,E251,E261,E271,E272,E302,E401,E402,E501,F401,E701,E702
 
 [tox]
 envlist = py27, py34, pypy

uncompyle6/disas.py

@@ -1,4 +1,4 @@
-#  Copyright (c) 2015-2016, 2818 by Rocky Bernstein
+#  Copyright (c) 2015-2016, 2818-2019 by Rocky Bernstein
 #  Copyright (c) 2005 by Dan Pascu <dan@windowmaker.org>
 #  Copyright (c) 2000-2002 by hartmut Goebel <h.goebel@crazy-compilers.com>
 #  Copyright (c) 1999 John Aycock
@@ -77,18 +77,18 @@ def disco_loop(disasm, queue, real_out):
             pass
         pass
 
-def disassemble_fp(fp, outstream=None):
-    """
-    disassemble Python byte-code from an open file
-    """
-    (version, timestamp, magic_int, co, is_pypy,
-     source_size) = load_from_fp(fp)
-    if type(co) == list:
-        for con in co:
-            disco(version, con, outstream)
-    else:
-        disco(version, co, outstream, is_pypy=is_pypy)
-    co = None
+# def disassemble_fp(fp, outstream=None):
+#     """
+#     disassemble Python byte-code from an open file
+#     """
+#     (version, timestamp, magic_int, co, is_pypy,
+#      source_size) = load_from_fp(fp)
+#     if type(co) == list:
+#         for con in co:
+#             disco(version, con, outstream)
+#     else:
+#         disco(version, co, outstream, is_pypy=is_pypy)
+#     co = None
 
 def disassemble_file(filename, outstream=None):
     """
@@ -120,5 +120,6 @@ def _test():
         fn = sys.argv[1]
     disassemble_file(fn)
 
+
 if __name__ == "__main__":
     _test()

uncompyle6/parser.py

@@ -37,7 +37,9 @@ class ParserError(Exception):
         return "Parse error at or near `%r' instruction at offset %s\n" % \
                (self.token, self.offset)
 
-nop_func = lambda self, args: None
+
+def nop_func(self, args):
+    return None
 
 class PythonParser(GenericASTBuilder):
 
@@ -792,6 +794,7 @@ def python_parser(version, co, out=sys.stdout, showasm=False,
     p = get_python_parser(version, parser_debug)
     return parse(p, tokens, customize)
 
+
 if __name__ == '__main__':
     def parse_test(co):
         from uncompyle6 import PYTHON_VERSION, IS_PYPY

uncompyle6/parsers/parse3.py

@@ -309,7 +309,7 @@ class Python3Parser(PythonParser):
         # FIXME: Common with 2.7
         ret_and  ::= expr JUMP_IF_FALSE_OR_POP ret_expr_or_cond COME_FROM
         ret_or   ::= expr JUMP_IF_TRUE_OR_POP ret_expr_or_cond COME_FROM
-        ret_cond ::= expr POP_JUMP_IF_FALSE expr RETURN_END_IF ret_expr_or_cond
+        ret_cond ::= expr POP_JUMP_IF_FALSE expr RETURN_END_IF COME_FROM ret_expr_or_cond
 
         or   ::= expr JUMP_IF_TRUE_OR_POP expr COME_FROM
         and  ::= expr JUMP_IF_FALSE_OR_POP expr COME_FROM
@@ -583,7 +583,6 @@ class Python3Parser(PythonParser):
               stmt ::= assign2_pypy
               assign3_pypy       ::= expr expr expr store store store
               assign2_pypy       ::= expr expr store store
-              return_if_lambda   ::= RETURN_END_IF_LAMBDA
               stmt               ::= conditional_lambda
               stmt               ::= conditional_not_lambda
               conditional_lambda ::= expr jmp_false expr return_if_lambda

uncompyle6/parsers/parse36.py

@@ -46,6 +46,10 @@ class Python36Parser(Python35Parser):
         # RETURN_VALUE is meant. Specifcally this can happen in
         # ifelsestmt -> ...else_suite _. suite_stmts... (last) stmt
         return ::= ret_expr RETURN_END_IF
+        return ::= ret_expr RETURN_VALUE COME_FROM
+        return_stmt_lambda ::= ret_expr RETURN_VALUE_LAMBDA COME_FROM
+        return_if_lambda   ::= RETURN_END_IF_LAMBDA COME_FROM
+
 
         # A COME_FROM is dropped off because of JUMP-to-JUMP optimization
         and  ::= expr jmp_false expr

uncompyle6/scanner.py

@@ -351,9 +351,9 @@ class Scanner(object):
 
         return result
 
-
     # FIXME: this is broken on 3.6+. Replace remaining (2.x-based) calls
     # with inst_matches
+
     def all_instr(self, start, end, instr, target=None, include_beyond_target=False):
         """
         Find all `instr` in the block from start to end.
@@ -423,8 +423,8 @@ class Scanner(object):
         last_was_extarg = False
         n = len(instructions)
         for i, inst in enumerate(instructions):
-            if (inst.opname == 'EXTENDED_ARG' and
-                i+1 < n and instructions[i+1].opname != 'MAKE_FUNCTION'):
+            if (inst.opname == 'EXTENDED_ARG'
+                and i+1 < n and instructions[i+1].opname != 'MAKE_FUNCTION'):
                 last_was_extarg = True
                 starts_line = inst.starts_line
                 is_jump_target = inst.is_jump_target
@@ -527,6 +527,7 @@ def get_scanner(version, is_pypy=False, show_asm=None):
         raise RuntimeError("Unsupported Python version %s" % version)
     return scanner
 
+
 if __name__ == "__main__":
     import inspect, uncompyle6
     co = inspect.currentframe().f_code

uncompyle6/scanners/scanner3.py

@@ -920,6 +920,10 @@ class Scanner3(Scanner):
                                 return
                             pass
                     pass
+
+                if self.version >= 3.4:
+                    self.fixed_jumps[offset] = rtarget
+
                 if code[pre_rtarget] == self.opc.RETURN_VALUE:
                     # If we are at some sort of POP_JUMP_IF and the instruction before was
                     # COMPARE_OP exception-match, then pre_rtarget is not an end_if