avoid list building when in-testing against dir() result

Cython/Compiler/ParseTreeTransforms.py

@@ -2495,6 +2495,20 @@ class TransformBuiltinMethods(EnvTransform):
                       for var in local_names ]
             return ExprNodes.ListNode(pos, args=items)
 
+    def visit_PrimaryCmpNode(self, node):
+        # special case: for in/not-in test, we do not need to sort locals()
+        self.visitchildren(node)
+        if node.operator in 'not_in':  # in/not_in
+            if isinstance(node.operand2, ExprNodes.SortedDictKeysNode):
+                arg = node.operand2.arg
+                if isinstance(arg, ExprNodes.NoneCheckNode):
+                    arg = arg.arg
+                node.operand2 = arg
+        return node
+
+    def visit_CascadedCmpNode(self, node):
+        return self.visit_PrimaryCmpNode(node)
+
     def _inject_eval(self, node, func_name):
         lenv = self.current_env()
         entry = lenv.lookup_here(func_name)

tests/run/locals_T732.pyx

@@ -2,10 +2,13 @@
 # ticket: 731
 # tags: locals, vars, dir
 
+cimport cython
+
 LOCALS = locals()
 GLOBALS = globals()
 DIR_SAME = sorted(dir()) == sorted(globals().keys())
 
+
 def test_module_locals_and_dir():
     """
     >>> LOCALS is GLOBALS
@@ -14,6 +17,7 @@ def test_module_locals_and_dir():
     True
     """
 
+
 def test_class_locals_and_dir():
     """
     >>> klass = test_class_locals_and_dir()
@@ -28,3 +32,33 @@ def test_class_locals_and_dir():
         names = dir()
         locs = locals()
     return Foo
+
+
+@cython.test_fail_if_path_exists('//SortedDictKeysNode')
+def test_class_dir_contains():
+    """
+    >>> klass = test_class_dir_contains()
+    True
+    False
+    True
+    False
+    True
+    False
+    True
+    True
+    True
+    """
+    not_visible = 1234
+    class Foo:
+        visible = 4321
+        print('visible' in dir())
+        print('not_visible' in dir())
+        print('not_visible' not in dir())
+        print('locs' in dir())
+        print('visible' in locals())
+        print('locs' in locals())
+        locs = locals()
+        print('visible' in dir())
+        print('locs' in dir())
+        print('locs' in locals())
+    return Foo