From c1668ded37cbbe54be5a63a87954932d7bf74db8 Mon Sep 17 00:00:00 2001
From: Ivan Malison <IvanMalison@gmail.com>
Date: Thu, 20 Aug 2015 02:11:55 -0700
Subject: [PATCH] singleton with metaclass

---
 dotfiles/lib/python/singleton.py      | 24 ++++++++++++++++++++++++
 dotfiles/lib/python/singleton_test.py | 15 +++++++++++++++
 2 files changed, 39 insertions(+)
 create mode 100644 dotfiles/lib/python/singleton.py
 create mode 100644 dotfiles/lib/python/singleton_test.py

diff --git a/dotfiles/lib/python/singleton.py b/dotfiles/lib/python/singleton.py
new file mode 100644
index 00000000..6d9e28e8
--- /dev/null
+++ b/dotfiles/lib/python/singleton.py
@@ -0,0 +1,24 @@
+def singleton(klass):
+    original_init = klass.__dict__.get('__init__')
+    class klassMeta(type, klass):
+
+        def __init__(self, *args):
+            original_init(self)
+            super(klass, self).__init__(*args)
+
+    class Temp(object):
+        __metaclass__ = klassMeta
+    Temp.__name__ = klass.__name__
+    klassMeta.__name__ = "{}Meta".format(klass.__name__)
+    return Temp
+
+
+@singleton
+class TestSingleton(object):
+
+    def __init__(self):
+        self.a = 22
+        self.b = 44
+
+    def hey(self):
+        return self.a + self.b
diff --git a/dotfiles/lib/python/singleton_test.py b/dotfiles/lib/python/singleton_test.py
new file mode 100644
index 00000000..404ecf37
--- /dev/null
+++ b/dotfiles/lib/python/singleton_test.py
@@ -0,0 +1,15 @@
+from . import singleton
+
+
+def test_singleton():
+    @singleton.singleton
+    class TestSingleton(object):
+
+        def __init__(self):
+            self.a = 22
+            self.b = 44
+
+        def hey(self):
+            return self.a + self.b
+    assert TestSingleton.a == 22
+    assert TestSingleton.hey() == 66