From e94416704d70d64b21afb44569039f2b50db966f Mon Sep 17 00:00:00 2001
From: Armin Ronacher <armin.ronacher@active-4.com>
Date: Sun, 18 Sep 2011 15:03:35 +0200
Subject: [PATCH] Added the flaskext_compat module to support flask.ext in 0.7
 and earlier.

---
 scripts/flaskext_compat.py | 73 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 73 insertions(+)
 create mode 100644 scripts/flaskext_compat.py

diff --git a/scripts/flaskext_compat.py b/scripts/flaskext_compat.py
new file mode 100644
index 00000000..ddc7e097
--- /dev/null
+++ b/scripts/flaskext_compat.py
@@ -0,0 +1,73 @@
+# -*- coding: utf-8 -*-
+"""
+    flaskext_compat
+    ~~~~~~~~~~~~~~~
+
+    Implements the ``flask.ext`` virtual package for versions of Flask
+    older than 0.7.  This module is a noop if Flask 0.8 was detected.
+
+    Usage::
+
+        import flaskext_compat
+        from flask.ext import foo
+
+    :copyright: (c) 2011 by Armin Ronacher.
+    :license: BSD, see LICENSE for more details.
+"""
+
+
+class _ExtensionImporter(object):
+    """This importer redirects imports from this submodule to other locations.
+    This makes it possible to transition from the old flaskext.name to the
+    newer flask_name without people having a hard time.
+    """
+    _module_choices = ['flask_%s', 'flaskext.%s']
+
+    def __init__(self):
+        from sys import meta_path
+        self.prefix = __name__ + '.'
+        self.prefix_cutoff = __name__.count('.') + 1
+
+        # since people might reload the flask.ext module (by accident or
+        # intentionally) we have to make sure to not add more than one
+        # import hook.  We can't check class types here either since a new
+        # class will be created on reload.  As a result of that we check
+        # the name of the class and remove stale instances.
+        def _name(x):
+            cls = type(x)
+            return cls.__module__ + '.' + cls.__name__
+        this = _name(self)
+        meta_path[:] = [x for x in meta_path if _name(x) != this] + [self]
+
+    def find_module(self, fullname, path=None):
+        if fullname.startswith(self.prefix):
+            return self
+
+    def load_module(self, fullname):
+        from sys import modules
+        if fullname in modules:
+            return modules[fullname]
+        modname = fullname.split('.', self.prefix_cutoff)[self.prefix_cutoff]
+        for path in self._module_choices:
+            realname = path % modname
+            try:
+                __import__(realname)
+            except ImportError:
+                continue
+            module = modules[fullname] = modules[realname]
+            if '.' not in modname:
+                setattr(modules[__name__], modname, module)
+            return module
+        raise ImportError(fullname)
+
+
+import sys
+import flask
+try:
+    __import__('flask.ext')
+except ImportError:
+    sys.modules['flask.ext'] = flask.ext = sys.modules[__name__]
+    __name__ = __package__ = 'flask.ext'
+    __path__ = []
+    _ExtensionImporter()
+del _ExtensionImporter, sys, flask