Merge pull request #262 from rocky/ifelif

reinstate some elif's

uncompyle6/parsers/parse26.py

@@ -102,6 +102,8 @@ class Python26Parser(Python2Parser):
 
     def p_stmt26(self, args):
         """
+        stmt ::= ifelsestmtr
+
         # We use filler as a placeholder to keep nonterminal positions
         # the same across different grammars so that the same semantic actions
         # can be used
@@ -173,6 +175,8 @@ class Python26Parser(Python2Parser):
         iflaststmt     ::= testexpr_then c_stmts_opt JUMP_ABSOLUTE come_froms POP_TOP
         iflaststmt     ::= testexpr      c_stmts_opt JUMP_ABSOLUTE come_froms POP_TOP
 
+        ifelsestmtr    ::= testexpr_then return_if_stmts returns
+
         testexpr_then  ::= testtrue_then
         testexpr_then  ::= testfalse_then
         testtrue_then  ::= expr jmp_true_then

uncompyle6/parsers/parse27.py

@@ -127,6 +127,8 @@ class Python27Parser(Python2Parser):
 
     def p_stmt27(self, args):
         """
+        stmt ::= ifelsestmtr
+
         # assert condition
         assert        ::= assert_expr jmp_true LOAD_ASSERT RAISE_VARARGS_1
 
@@ -178,6 +180,7 @@ class Python27Parser(Python2Parser):
         ifelsestmtc       ::= testexpr c_stmts_opt JUMP_ABSOLUTE else_suitec
         ifelsestmtl       ::= testexpr c_stmts_opt JUMP_BACK else_suitel
         ifelsestmtl       ::= testexpr c_stmts_opt CONTINUE else_suitel
+        ifelsestmtr       ::= testexpr return_if_stmts COME_FROM returns
 
         # Common with 2.6
         return_if_lambda   ::= RETURN_END_IF_LAMBDA COME_FROM

uncompyle6/parsers/parse3.py

@@ -95,7 +95,7 @@ class Python3Parser(PythonParser):
     def p_grammar(self, args):
         """
         sstmt ::= stmt
-        sstmt ::= ifelsestmtr
+        stmt  ::= ifelsestmtr
         sstmt ::= return RETURN_LAST
 
         return_if_stmts ::= return_if_stmt come_from_opt

uncompyle6/semantics/consts.py

@@ -353,12 +353,16 @@ TABLE_DIRECT = {
     'ifelsestmt':	( '%|if %c:\n%+%c%-%|else:\n%+%c%-', 0, 1, 3 ),
     'ifelsestmtc':	( '%|if %c:\n%+%c%-%|else:\n%+%c%-', 0, 1, 3 ),
     'ifelsestmtl':	( '%|if %c:\n%+%c%-%|else:\n%+%c%-', 0, 1, 3 ),
+    'ifelsestmtr':	( '%|if %c:\n%+%c%-%|else:\n%+%c%-', 0, 1, 2 ),
+    'ifelsestmtr2':	( '%|if %c:\n%+%c%-%|else:\n%+%c%-\n\n', 0, 1, 3 ), # has COME_FROM
+
+
+    # "elif" forms are not generated by the parser but are created through tree
+    # transformations. See "n_ifelsestmt".
     'ifelifstmt':	( '%|if %c:\n%+%c%-%c', 0, 1, 3 ),
     'elifelifstmt':	( '%|elif %c:\n%+%c%-%c', 0, 1, 3 ),
     'elifstmt':		( '%|elif %c:\n%+%c%-', 0, 1 ),
     'elifelsestmt':	( '%|elif %c:\n%+%c%-%|else:\n%+%c%-', 0, 1, 3 ),
-    'ifelsestmtr':	( '%|if %c:\n%+%c%-%|else:\n%+%c%-', 0, 1, 2 ),
-    'ifelsestmtr2':	( '%|if %c:\n%+%c%-%|else:\n%+%c%-\n\n', 0, 1, 3 ), # has COME_FROM
     'elifelsestmtr':	( '%|elif %c:\n%+%c%-%|else:\n%+%c%-\n\n', 0, 1, 2 ),
     'elifelsestmtr2':	( '%|elif %c:\n%+%c%-%|else:\n%+%c%-\n\n', 0, 1, 3 ), # has COME_FROM
 

uncompyle6/semantics/pysource.py

@@ -646,15 +646,31 @@ class SourceWalker(GenericASTTraversal, object):
         self.println()
         self.prune() # stop recursing
 
+    # preprocess is used for handling chains of
+    # if elif elif
     def n_ifelsestmt(self, node, preprocess=False):
+        """
+        Here we turn:
+
+          if ...
+          else
+             if ..
+
+        into:
+
+          if ..
+          elif ...
+
+        where appropriate
+        """
         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'):
+        if len(n) == 1 == len(n[0]) and n[0] == 'stmt':
             n = n[0][0]
+        elif n[0].kind in ('lastc_stmt', 'lastl_stmt'):
+            n = n[0]
         else:
             if not preprocess:
                 self.default(node)