Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/lldb/examples/summaries/cocoa/attrib_fromdict.py

@@ -0,0 +1,42 @@
+"""
+Objective-C runtime wrapper for use by LLDB Python formatters
+
+part of The LLVM Compiler Infrastructure
+This file is distributed under the University of Illinois Open Source
+License. See LICENSE.TXT for details.
+"""
+
+
+class AttributesDictionary:
+
+    def __init__(self, allow_reset=True):
+        # need to do it this way to prevent endless recursion
+        self.__dict__['_dictionary'] = {}
+        self.__dict__['_allow_reset'] = allow_reset
+
+    def __getattr__(self, name):
+        if not self._check_exists(name):
+            return None
+        value = self._dictionary[name]
+        return value
+
+    def _set_impl(self, name, value):
+        self._dictionary[name] = value
+
+    def _check_exists(self, name):
+        return name in self._dictionary
+
+    def __setattr__(self, name, value):
+        if self._allow_reset:
+            self._set_impl(name, value)
+        else:
+            self.set_if_necessary(name, value)
+
+    def set_if_necessary(self, name, value):
+        if not self._check_exists(name):
+            self._set_impl(name, value)
+            return True
+        return False
+
+    def __len__(self):
+        return len(self._dictionary)