Bug #1588287: fix invalid assertion for `1,2` in debug builds.

Will backport

Lib/test/test_grammar.py

@@ -747,6 +747,8 @@ hello world
 
         x = `x`
         x = `1 or 2 or 3`
+        self.assertEqual(`1,2`, '(1, 2)')
+
         x = x
         x = 'x'
         x = 123

Misc/NEWS

@@ -12,6 +12,8 @@ What's New in Python 2.6 alpha 1?
 Core and builtins
 -----------------
 
+- Bug #1588287: fix invalid assertion for `1,2` in debug builds.
+
 - Bug #1576657: when setting a KeyError for a tuple key, make sure that
   the tuple isn't used as the "exception arguments tuple".
 

Python/ast.c

@@ -532,6 +532,7 @@ seq_for_testlist(struct compiling *c, const node *n)
            || TYPE(n) == listmaker
            || TYPE(n) == testlist_gexp
            || TYPE(n) == testlist_safe
+           || TYPE(n) == testlist1
            );
 
     seq = asdl_seq_new((NCH(n) + 1) / 2, c->c_arena);