1 files changed, 19 insertions, 9 deletions
diff --git a/railties/lib/rails/command.rb b/railties/lib/rails/command.rb
index 13f3b90b6d..0d4e6dc5a1 100644
--- a/railties/lib/rails/command.rb
+++ b/railties/lib/rails/command.rb
@@ -27,15 +27,23 @@ module Rails
       end
 
       # Receives a namespace, arguments and the behavior to invoke the command.
-      def invoke(namespace, args = [], **config)
-        namespace = namespace.to_s
-        namespace = "help" if namespace.blank? || HELP_MAPPINGS.include?(namespace)
-        namespace = "version" if %w( -v --version ).include? namespace
+      def invoke(full_namespace, args = [], **config)
+        namespace = full_namespace = full_namespace.to_s
 
-        if command = find_by_namespace(namespace)
-          command.perform(namespace, args, config)
+        if char = namespace =~ /:(\w+)$/
+          command_name, namespace = $1, namespace.slice(0, char)
         else
-          find_by_namespace("rake").perform(namespace, args, config)
+          command_name = namespace
+        end
+
+        command_name, namespace = "help", "help" if command_name.blank? || HELP_MAPPINGS.include?(command_name)
+        command_name, namespace = "version", "version" if %w( -v --version ).include?(command_name)
+
+        command = find_by_namespace(namespace, command_name)
+        if command && command.all_commands[command_name]
+          command.perform(command_name, args, config)
+        else
+          find_by_namespace("rake").perform(full_namespace, args, config)
         end
       end
 
@@ -52,8 +60,10 @@ module Rails
       #
       # Notice that "rails:commands:webrat" could be loaded as well, what
       # Rails looks for is the first and last parts of the namespace.
-      def find_by_namespace(name) # :nodoc:
-        lookups = [ name, "rails:#{name}" ]
+      def find_by_namespace(namespace, command_name = nil) # :nodoc:
+        lookups = [ namespace ]
+        lookups << "#{namespace}:#{command_name}" if command_name
+        lookups.concat lookups.map { |lookup| "rails:#{lookup}" }
 
         lookup(lookups)