bin/errors in flows-0.5.1 vs bin/errors in flows-0.6.0

@@ -15,10 +15,11 @@
 require_relative 'errors_cli/oc_error_demo'
 require_relative 'errors_cli/railway_error_demo'
 require_relative 'errors_cli/result_error_demo'
 require_relative 'errors_cli/scp_error_demo'
 require_relative 'errors_cli/flow_error_demo'
+require_relative 'errors_cli/interface_error_demo'
 
 class ErrorsCLI
   extend GLI::App
 
   program_desc 'Error reporting demo'
@@ -28,15 +29,15 @@
   def self.make_cmd(ctx, title, name) # rubocop:disable Metrics/AbcSize, Metrics/MethodLength
     ctx.desc title
     ctx.command name do |cmd|
       cmd.action do |_, _, _|
         puts title.green
-        puts(('BEGIN' + '-' * (title.length - 5)).color(:darkgray))
+        puts("BEGIN#{'-' * (title.length - 5)}".color(:darkgray))
         yield
       rescue StandardError => err
         puts err.message
-        puts(('END' + '-' * (title.length - 3)).color(:darkgray))
+        puts("END#{'-' * (title.length - 3)}".color(:darkgray))
         puts
       end
     end
   end
 
@@ -121,9 +122,16 @@
       FlowErrorDemo.no_first_node
     end
 
     make_cmd cmd, 'Invalid Node route', :invalid_node_route do
       FlowErrorDemo.invalid_node_route
+    end
+  end
+
+  desc 'Interface errors'
+  command :interface do |cmd|
+    make_cmd cmd, 'Missing Implementation', :missing_implementation do
+      InterfaceErrorDemo.missing_implementation
     end
   end
 end
 
 exit ErrorsCLI.run(ARGV)