Start going over Python 2.5 bytecode

Fix 2.6 with bug

test/add-test.py

@@ -9,4 +9,5 @@ version = sys.version[0:3]
 cfile =  "bytecode_%s/%s" % (version, short) + 'c'
 print("byte-compiling %s to %s" % (path, cfile))
 py_compile.compile(path, cfile)
-os.system("../bin/uncompyle6 -a -t %s" % cfile)
+if sys.version >= (2, 6, 0):
+    os.system("../bin/uncompyle6 -a -t %s" % cfile)

test/simple_source/stmts/05_with.py

@@ -1,2 +1,3 @@
+from __future__ import with_statement
 with (sys) as f:
     print(f)

uncompyle6/parser.py

@@ -592,12 +592,11 @@ def get_python_parser(version, debug_parser, compile_mode='exec'):
             else:
                 p = parse23.Python23ParserSingle(debug_parser)
         elif version == 2.5:
-            # For now, we'll consider 2.5 exactly like 2.6
-            import uncompyle6.parsers.parse26 as parse25
+            import uncompyle6.parsers.parse25 as parse25
             if compile_mode == 'exec':
-                p = parse25.Python26Parser(debug_parser)
+                p = parse25.Python25Parser(debug_parser)
             else:
-                p = parse25.Python26ParserSingle(debug_parser)
+                p = parse25.Python25ParserSingle(debug_parser)
         elif version == 2.6:
             import uncompyle6.parsers.parse26 as parse26
             if compile_mode == 'exec':

uncompyle6/parsers/parse25.py

@@ -0,0 +1,42 @@
+#  Copyright (c) 2016 Rocky Bernstein
+"""
+spark grammar differences over Python2.6 for Python 2.6.
+"""
+
+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_misc(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
+
+        # Pyython 2.6 uses ROT_TWO instead of the STORE_FAST
+        setupwithas ::= DUP_TOP LOAD_ATTR STORE_FAST LOAD_ATTR CALL_FUNCTION_0 STORE_FAST
+                        SETUP_FINALLY LOAD_FAST DELETE_FAST
+
+        # Python 2.6 omits ths LOAD_FAST DELETE_FAST below
+        withasstmt ::= expr setupwithas designator suite_stmts_opt
+                       POP_BLOCK LOAD_CONST COME_FROM
+                       LOAD_FAST DELETE_FAST
+                       WITH_CLEANUP END_FINALLY
+
+
+        '''
+
+class Python25ParserSingle(Python26Parser, PythonParserSingle):
+    pass
+
+if __name__ == '__main__':
+    # Check grammar
+    p = Python26Parser()
+    p.checkGrammar()

uncompyle6/parsers/parse26.py

@@ -128,6 +128,7 @@ class Python26Parser(Python2Parser):
                      POP_BLOCK LOAD_CONST COME_FROM WITH_CLEANUP END_FINALLY
 
         # Semantic actions want designator to be at index 2
+        # Rule is possibly 2.6 only
         withasstmt ::= expr setupwithas designator suite_stmts_opt
                        POP_BLOCK LOAD_CONST COME_FROM WITH_CLEANUP END_FINALLY
 
@@ -135,8 +136,12 @@ class Python26Parser(Python2Parser):
         # opcode SETUP_WITH
         setupwith ::= DUP_TOP LOAD_ATTR ROT_TWO LOAD_ATTR CALL_FUNCTION_0 POP_TOP
 
-        setupwithas ::= DUP_TOP LOAD_ATTR ROT_TWO LOAD_ATTR CALL_FUNCTION_0 STORE_FAST
-                        SETUP_FINALLY LOAD_FAST DELETE_FAST
+        # Possibly 2.6 only
+        setupwithas ::= DUP_TOP LOAD_ATTR ROT_TWO LOAD_ATTR CALL_FUNCTION_0 setup_finally
+
+        setup_finally ::= STORE_FAST SETUP_FINALLY LOAD_FAST DELETE_FAST
+        setup_finally ::= STORE_NAME SETUP_FINALLY LOAD_NAME DELETE_NAME
+
 
         whilestmt ::= SETUP_LOOP testexpr l_stmts_opt jb_pop POP_BLOCK _come_from
         whilestmt ::= SETUP_LOOP testexpr l_stmts_opt jb_cf_pop bp_come_from