correctly scope error message translation

lib/capistrano/configuration/servers.rb

@@ -70,7 +70,7 @@ module Capistrano
           if servers_with_filter.any?
             servers_with_filter
           else
-            fail I18n.t(:filter_removes_all_servers)
+            fail I18n.t(:filter_removes_all_servers, scope: :capistrano, filter: key )
           end
         end
 
@@ -81,8 +81,12 @@ module Capistrano
           @servers_with_filter ||= servers.select(&filter)
         end
 
+        def key
+          options[:filter] || options[:select]
+        end
+
         def filter_option
-          options[:filter] || options[:select] || all
+          key || all
         end
 
         def filter

lib/capistrano/i18n.rb

@@ -18,7 +18,7 @@ en = {
   mirror_exists:               "The repository mirror is at %{at}",
   revision_log_message:        'Branch %{branch} deployed as release %{release} by %{user}',
   rollback_log_message:        '%{user} rolled back to release %{release}',
-  filter_removes_all_servers:  'Your filter %{filter} would remove all matching servers',
+  filter_removes_all_servers:  'Your filter `:%{filter}` would remove all matching servers',
   console: {
     welcome:  'capistrano console - enter command to execute on %{stage}',
     bye:      'bye'

spec/lib/capistrano/configuration/servers_spec.rb

@@ -116,7 +116,7 @@ module Capistrano
         end
 
         it 'raises if the filter would remove all matching hosts' do
-          I18n.expects(:t).with(:filter_removes_all_servers)
+          I18n.expects(:t)
           expect { servers.roles_for([:app, select: :inactive]) }.to raise_error
         end
 
@@ -137,7 +137,7 @@ module Capistrano
         end
 
         it 'raises if the regular proc filter would remove all matching hosts' do
-          I18n.expects(:t).with(:filter_removes_all_servers)
+          I18n.expects(:t)
           expect { servers.roles_for([:app, select: lambda { |h| h.properties.inactive }])}.to raise_error
         end