prevent assignment to set literals

3 files changed, 9 insertions, 0 deletions

diff --git a/Lib/test/test_syntax.py b/Lib/test/test_syntax.py
index 899db61d17..4992a32a8e 100644
--- a/Lib/test/test_syntax.py
+++ b/Lib/test/test_syntax.py
@@ -468,6 +468,12 @@ Traceback (most recent call last):
   File "<doctest test.test_syntax[50]>", line 1
 SyntaxError: can't delete ()
 
+>>> {1, 2, 3} = 42
+Traceback (most recent call last):
+   ...
+   File "<doctest test.test_syntax[50]>", line 1
+SyntaxError: can't assign to literal
+
 """
 
 import re
diff --git a/Misc/NEWS b/Misc/NEWS
index cb60239138..70ce171577 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,8 @@ What's New in Python 2.7?
 Core and Builtins
 -----------------
 
+- Prevent assignment to set literals.
+
 Library
 -------
 
diff --git a/Python/ast.c b/Python/ast.c
index 41c0d28e1b..f8c83d934c 100644
--- a/Python/ast.c
+++ b/Python/ast.c
@@ -440,6 +440,7 @@ set_context(struct compiling *c, expr_ty e, expr_context_ty ctx, const node *n)
             expr_name = "dict comprehension";
             break;
         case Dict_kind:
+        case Set_kind:
         case Num_kind:
         case Str_kind:
             expr_name = "literal";