[Python-checkins] r73405 - in python/trunk: Lib/test/test_compile.py Misc/NEWS Python/ast.c

Sat Jun 13 05:46:31 CEST 2009

Author: benjamin.peterson
Date: Sat Jun 13 05:46:30 2009
New Revision: 73405
Log:
prevent import statements from assigning to None
Modified:
 python/trunk/Lib/test/test_compile.py
 python/trunk/Misc/NEWS
 python/trunk/Python/ast.c
Modified: python/trunk/Lib/test/test_compile.py
==============================================================================

--- python/trunk/Lib/test/test_compile.py	(original)
+++ python/trunk/Lib/test/test_compile.py	Sat Jun 13 05:46:30 2009
@@ -270,11 +270,17 @@
 '(a, None) = 0, 0',
 'for None in range(10): pass',
 'def f(None): pass',
+ 'import None',
+ 'import x as None',
+ 'from x import None',
+ 'from x import y as None'
 ]
 for stmt in stmts:
 stmt += "\n"
 self.assertRaises(SyntaxError, compile, stmt, 'tmp', 'single')
 self.assertRaises(SyntaxError, compile, stmt, 'tmp', 'exec')
+ # This is ok.
+ compile("from None import x", "tmp", "exec")
 
 def test_import(self):
 succeed = [
Modified: python/trunk/Misc/NEWS
==============================================================================
--- python/trunk/Misc/NEWS	(original)
+++ python/trunk/Misc/NEWS	Sat Jun 13 05:46:30 2009
@@ -12,6 +12,8 @@
 Core and Builtins
 -----------------
 
+- Assignment to None using import statements now raises a SyntaxError.
+
 - In the slice AST type, the step field will always be None if a step expression
 is not specified.
 
Modified: python/trunk/Python/ast.c
==============================================================================
--- python/trunk/Python/ast.c	(original)
+++ python/trunk/Python/ast.c	Sat Jun 13 05:46:30 2009
@@ -2294,7 +2294,7 @@
 }
 
 static alias_ty
-alias_for_import_name(struct compiling *c, const node *n)
+alias_for_import_name(struct compiling *c, const node *n, int store)
 {
 /*
 import_as_name: NAME ['as' NAME]
@@ -2305,28 +2305,38 @@
 
 loop:
 switch (TYPE(n)) {
- case import_as_name:
+ case import_as_name: {
+ node *name_node = CHILD(n, 0);
 str = NULL;
 if (NCH(n) == 3) {
- str = NEW_IDENTIFIER(CHILD(n, 2));
+ node *str_node = CHILD(n, 2);
+ if (store && !forbidden_check(c, str_node, STR(str_node)))
+ return NULL;
+ str = NEW_IDENTIFIER(str_node);
 if (!str)
 return NULL;
 }
- name = NEW_IDENTIFIER(CHILD(n, 0));
+ if (!forbidden_check(c, name_node, STR(name_node)))
+ return NULL;
+ name = NEW_IDENTIFIER(name_node);
 if (!name)
 return NULL;
 return alias(name, str, c->c_arena);
+ }
 case dotted_as_name:
 if (NCH(n) == 1) {
 n = CHILD(n, 0);
 goto loop;
 }
 else {
- alias_ty a = alias_for_import_name(c, CHILD(n, 0));
+ node *asname_node = CHILD(n, 2);
+ alias_ty a = alias_for_import_name(c, CHILD(n, 0), store);
 if (!a)
 return NULL;
 assert(!a->asname);
- a->asname = NEW_IDENTIFIER(CHILD(n, 2));
+ if (store && !forbidden_check(c, asname_node, STR(asname_node)))
+ return NULL;
+ a->asname = NEW_IDENTIFIER(asname_node);
 if (!a->asname)
 return NULL;
 return a;
@@ -2334,7 +2344,10 @@
 break;
 case dotted_name:
 if (NCH(n) == 1) {
- name = NEW_IDENTIFIER(CHILD(n, 0));
+ node *name_node = CHILD(n, 0);
+ if (store && !forbidden_check(c, name_node, STR(name_node)))
+ return NULL;
+ name = NEW_IDENTIFIER(name_node);
 if (!name)
 return NULL;
 return alias(name, NULL, c->c_arena);
@@ -2408,7 +2421,7 @@
 if (!aliases)
 return NULL;
 for (i = 0; i < NCH(n); i += 2) {
- alias_ty import_alias = alias_for_import_name(c, CHILD(n, i));
+ alias_ty import_alias = alias_for_import_name(c, CHILD(n, i), 1);
 if (!import_alias)
 return NULL;
 asdl_seq_SET(aliases, i / 2, import_alias);
@@ -2425,7 +2438,9 @@
 optional module name */
 for (idx = 1; idx < NCH(n); idx++) {
 if (TYPE(CHILD(n, idx)) == dotted_name) {
- mod = alias_for_import_name(c, CHILD(n, idx));
+ mod = alias_for_import_name(c, CHILD(n, idx), 0);
+ if (!mod)
+ return NULL;
 idx++;
 break;
 } else if (TYPE(CHILD(n, idx)) != DOT) {
@@ -2466,14 +2481,14 @@
 
 /* handle "from ... import *" special b/c there's no children */
 if (TYPE(n) == STAR) {
- alias_ty import_alias = alias_for_import_name(c, n);
+ alias_ty import_alias = alias_for_import_name(c, n, 1);
 if (!import_alias)
 return NULL;
 asdl_seq_SET(aliases, 0, import_alias);
 }
 else {
 for (i = 0; i < NCH(n); i += 2) {
- alias_ty import_alias = alias_for_import_name(c, CHILD(n, i));
+ alias_ty import_alias = alias_for_import_name(c, CHILD(n, i), 1);
 if (!import_alias)
 return NULL;
 asdl_seq_SET(aliases, i / 2, import_alias);
