[puppetlabs#1058] Add accessor for a module's cachedir

lib/r10k/module/base.rb

@@ -99,6 +99,14 @@ def properties
     raise NotImplementedError
   end
 
+  # Return the module's cachedir. Subclasses that implement a cache
+  # will override this to return a real directory location.
+  #
+  # @return [String, :none]
+  def cachedir
+    :none
+  end
+
   private
 
   def parse_title(title)

lib/r10k/module/git.rb

@@ -57,6 +57,10 @@ def status
     @repo.status(version)
   end
 
+  def cachedir
+    @repo.cache.sanitized_dirname
+  end
+
   private
 
   def validate_ref(desired, default)

lib/r10k/puppetfile.rb

@@ -143,7 +143,7 @@ def add_module(name, args)
     mod.origin = 'Puppetfile'
 
     @managed_content[install_path] << mod.name
-    cachedir = module_vcs_cachedir(mod)
+    cachedir = mod.cachedir
     @modules_by_vcs_cachedir[cachedir] ||= []
     @modules_by_vcs_cachedir[cachedir] << mod
     @modules << mod
@@ -189,19 +189,6 @@ def accept(visitor)
 
   private
 
-  def module_vcs_cachedir(mod)
-    if mod.respond_to? :repo
-      repo = mod.repo
-      if repo.respond_to? :cache
-        cache = repo.cache
-        if cache.respond_to? :sanitized_dirname
-          return cache.sanitized_dirname
-        end
-      end
-    end
-    :none
-  end
-
   def serial_accept(visitor)
     visitor.visit(:puppetfile, self) do
       modules.each do |mod|