From 806ea1f6ca2b1b50bb4634be6c39ad83d8af7e89 Mon Sep 17 00:00:00 2001
From: Paul Sokolovsky
Date: Thu, 22 May 2014 00:32:00 +0300
Subject: py: Initial attempts to actually allow implementing __new__ in
 Python.

Caveat is that __new__ should recurse to base class __new__, and ultimately,
object.__new__ is what handles instance allocation.
---
 tests/basics/class_new.py  | 21 +++++++++++++++++++++
 tests/basics/object_new.py | 20 ++++++++++++++++++++
 2 files changed, 41 insertions(+)
 create mode 100644 tests/basics/class_new.py
 create mode 100644 tests/basics/object_new.py

(limited to 'tests')

diff --git a/tests/basics/class_new.py b/tests/basics/class_new.py
new file mode 100644
index 000000000..7fedcab6c
--- /dev/null
+++ b/tests/basics/class_new.py
@@ -0,0 +1,21 @@
+class A:
+
+    @staticmethod
+    def __new__(cls):
+        print("A.__new__")
+        return super(cls, A).__new__(cls)
+
+    def __init__(self):
+        pass
+
+    def meth(self):
+        pass
+
+#print(A.__new__)
+#print(A.__init__)
+
+a = A()
+
+#print(a.meth)
+#print(a.__init__)
+#print(a.__new__)
diff --git a/tests/basics/object_new.py b/tests/basics/object_new.py
new file mode 100644
index 000000000..6131ed337
--- /dev/null
+++ b/tests/basics/object_new.py
@@ -0,0 +1,20 @@
+# object.__new__(cls) is the only way in Python to allocate empty
+# (non-initialized) instance of class.
+# See e.g. http://infohost.nmt.edu/tcc/help/pubs/python/web/new-new-method.html
+# TODO: Find reference in CPython docs
+
+class Foo:
+
+    def __init__(self):
+        print("in __init__")
+        self.attr = "something"
+
+
+o = object.__new__(Foo)
+#print(o)
+print(hasattr(o, "attr"))
+print(isinstance(o, Foo))
+o.__init__()
+#print(dir(o))
+print(hasattr(o, "attr"))
+print(o.attr)
-- 
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