Noargs exec()

Cython/Compiler/ParseTreeTransforms.py

@@ -2250,6 +2250,17 @@ class TransformBuiltinMethods(EnvTransform):
                 error(node.pos, u"'%s' not a valid cython attribute or is being used incorrectly" % attribute)
         return node
 
+    def visit_ExecStatNode(self, node):
+        lenv = self.current_env()
+        self.visitchildren(node)
+        if len(node.args) == 1:
+            node.args.append(ExprNodes.GlobalsExprNode(node.pos))
+            if not lenv.is_module_scope:
+                node.args.append(
+                    ExprNodes.LocalsExprNode(
+                        node.pos, self.current_scope_node(), lenv))
+        return node
+
     def _inject_locals(self, node, func_name):
         # locals()/dir()/vars() builtins
         lenv = self.current_env()

Cython/Compiler/Parsing.py

@@ -1124,8 +1124,6 @@ def p_exec_statement(s):
         if s.sy == ',':
             s.next()
             args.append(p_test(s))
-    else:
-        error(pos, "'exec' currently requires a target mapping (globals/locals)")
     return Nodes.ExecStatNode(pos, args = args)
 
 def p_del_statement(s):

tests/run/exec_noargs.pyx

+# mode: run
+# tags: exec
+
+exec "GLOBAL = 1234"
+
+def exec_module_scope():
+    """
+    >>> globals()['GLOBAL']
+    1234
+    """
+
+def exec_func_scope():
+    """
+    >>> exec_func_scope()
+    {'a': 'b', 'G': 1234}
+    """
+    d = {}
+    exec "d['a'] = 'b'; d['G'] = GLOBAL"
+    return d
+
+def exec_pyclass_scope():
+    """
+    >>> obj = exec_pyclass_scope()
+    >>> obj.a
+    'b'
+    >>> obj.G
+    1234
+    """
+    class TestExec:
+        exec "a = 'b'; G = GLOBAL"
+    return TestExec