Registry keys and values were autorequiring all ancestors

Previously, registry keys and values were including all of their
ancestors in the array returned by the `autorequire` block. If the catalog
contained those resources, then puppet was creating one dependency edge
between the registry key/value and each ancestor. This is not desirable,
as we only need one dependency edges between the resource and its nearest
ancestor that we're managing.

Also, registry values were autorequiring themselves.

This commit changes the autorequire blocks using the same logic as is used
in the file type. We walk our ancestors, looking for the nearest
registry_key that we're managing.

It also changes the `ascend` method to exclude the current resource from
enumeration, since both registry_key and registry_value had to do extra
work to exclude itself from the autorequire.

Also removed a spurious downcase method. Currently, we only canonicalize
the root key (to handled mixed case). A future commit will resolve
case-insensitivity for registry key paths and value path and names.

lib/puppet/modules/registry/key_path.rb

@@ -49,8 +49,6 @@ def munge(path)
   def ascend(&block)
     p = self.value
 
-    yield p
-
     while idx = p.rindex('\\')
       p = p[0, idx]
       yield p

lib/puppet/modules/registry/value_path.rb

@@ -19,6 +19,6 @@ def munge(path)
     end
 
     canonical = subkey.empty? ?  "#{root}\\#{valuename}" : "#{root}\\#{subkey}\\#{valuename}"
-    canonical.downcase
+    canonical
   end
 end

lib/puppet/type/registry_key.rb

@@ -13,7 +13,12 @@ def self.title_patterns
   newparam(:path, :parent => Puppet::Modules::Registry::KeyPath, :namevar => true) do
   end
 
+  # Autorequire the nearest ancestor registry_key found in the catalog.
   autorequire(:registry_key) do
-    parameter(:path).enum_for(:ascend).select { |p| self[:path] != p }
+    req = []
+    if found = parameter(:path).enum_for(:ascend).find { |p| catalog.resource(:registry_key, p.to_s) }
+      req << found.to_s
+    end
+    req
   end
 end

lib/puppet/type/registry_value.rb

@@ -38,8 +38,13 @@ def self.title_patterns
     defaultto ''
   end
 
+  # Autorequire the nearest ancestor registry_key found in the catalog.
   autorequire(:registry_key) do
-    parameter(:path).enum_for(:ascend)
+    req = []
+    if found = parameter(:path).enum_for(:ascend).find { |p| catalog.resource(:registry_key, p.to_s) }
+      req << found.to_s
+    end
+    req
   end
 end