--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/rhodecode/lib/dbmigrate/migrate/versioning/pathed.py	Sat Dec 11 01:54:12 2010 +0100
@@ -0,0 +1,75 @@
+"""
+   A path/directory class.
+"""
+
+import os
+import shutil
+import logging
+
+from migrate import exceptions
+from migrate.versioning.config import *
+from migrate.versioning.util import KeyedInstance
+
+
+log = logging.getLogger(__name__)
+
+class Pathed(KeyedInstance):
+    """
+    A class associated with a path/directory tree.
+
+    Only one instance of this class may exist for a particular file;
+    __new__ will return an existing instance if possible
+    """
+    parent = None
+
+    @classmethod
+    def _key(cls, path):
+        return str(path)
+
+    def __init__(self, path):
+        self.path = path
+        if self.__class__.parent is not None:
+            self._init_parent(path)
+
+    def _init_parent(self, path):
+        """Try to initialize this object's parent, if it has one"""
+        parent_path = self.__class__._parent_path(path)
+        self.parent = self.__class__.parent(parent_path)
+        log.debug("Getting parent %r:%r" % (self.__class__.parent, parent_path))
+        self.parent._init_child(path, self)
+
+    def _init_child(self, child, path):
+        """Run when a child of this object is initialized.
+
+        Parameters: the child object; the path to this object (its
+        parent)
+        """
+
+    @classmethod
+    def _parent_path(cls, path):
+        """
+        Fetch the path of this object's parent from this object's path.
+        """
+        # os.path.dirname(), but strip directories like files (like
+        # unix basename)
+        #
+        # Treat directories like files...
+        if path[-1] == '/':
+            path = path[:-1]
+        ret = os.path.dirname(path)
+        return ret
+
+    @classmethod
+    def require_notfound(cls, path):
+        """Ensures a given path does not already exist"""
+        if os.path.exists(path):
+            raise exceptions.PathFoundError(path)
+
+    @classmethod
+    def require_found(cls, path):
+        """Ensures a given path already exists"""
+        if not os.path.exists(path):
+            raise exceptions.PathNotFoundError(path)
+
+    def __str__(self):
+        return self.path