Merge pull request #13341 from carlosantoniodasilva/ca-i18n

Default I18n.enforce_available_locales to true

We will default this option to true from now on to ensure users properly handle their list of available locales whenever necessary. This option was added as a security measure and thus Rails will follow it defaulting to secure option.

Also improve the handling of I18n config options in its railtie, taking the new enforce_available_locales option into account, by setting it as the last one in the process. This ensures no other configuration will trigger a deprecation warning due to that setting.

4 files changed, 27 insertions, 10 deletions

diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index 6a13db346d..c830ee61e6 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,3 +1,16 @@
+*   Default the new `I18n.enforce_available_locales` config to `true`, meaning
+    `I18n` will make sure that all locales passed to it must be declared in the
+    `available_locales` list.
+
+    To disable it add the following configuration to your application:
+
+        config.i18n.enforce_available_locales = false
+
+    This also ensures I18n configuration is properly initialized taking the new
+    option into account, to avoid their deprecations while booting up the app.
+
+    *Carlos Antonio da Silva*, *Yves Senn*
+
 *   Introduce Module#concerning: a natural, low-ceremony way to separate
     responsibilities within a class.
 
@@ -49,11 +62,6 @@
 
     *Mario Visic*
 
-*   Ensure `config.i18n.enforce_available_locales` is set before any other
-    configuration option.
-
-    *Yves Senn*
-
 *   Added `Date#all_week/month/quarter/year` for generating date ranges.
 
     *Dmitriy Meremyanin*
diff --git a/activesupport/activesupport.gemspec b/activesupport/activesupport.gemspec
index 0427022dc6..f3625e8b79 100644
--- a/activesupport/activesupport.gemspec
+++ b/activesupport/activesupport.gemspec
@@ -20,7 +20,7 @@ Gem::Specification.new do |s|
 
   s.rdoc_options.concat ['--encoding',  'UTF-8']
 
-  s.add_dependency 'i18n',       '~> 0.6', '>= 0.6.4'
+  s.add_dependency 'i18n',       '~> 0.6', '>= 0.6.9'
   s.add_dependency 'json',       '~> 1.7', '>= 1.7.7'
   s.add_dependency 'tzinfo',     '~> 1.1'
   s.add_dependency 'minitest',   '~> 5.1'
diff --git a/activesupport/lib/active_support/i18n_railtie.rb b/activesupport/lib/active_support/i18n_railtie.rb
index dcdea70443..ac9bca44b6 100644
--- a/activesupport/lib/active_support/i18n_railtie.rb
+++ b/activesupport/lib/active_support/i18n_railtie.rb
@@ -8,6 +8,8 @@ module I18n
     config.i18n.railties_load_path = []
     config.i18n.load_path = []
     config.i18n.fallbacks = ActiveSupport::OrderedOptions.new
+    # Enforce I18n to check the available locales when setting a locale.
+    config.i18n.enforce_available_locales = true
 
     # Set the i18n configuration after initialization since a lot of
     # configuration is still usually done in application initializers.
@@ -31,10 +33,11 @@ module I18n
 
       fallbacks = app.config.i18n.delete(:fallbacks)
 
-      if app.config.i18n.has_key?(:enforce_available_locales)
-        # this option needs to be set before `default_locale=` to work properly.
-        I18n.enforce_available_locales = app.config.i18n.delete(:enforce_available_locales)
-      end
+      # Avoid issues with setting the default_locale by disabling available locales
+      # check while configuring.
+      enforce_available_locales = app.config.i18n.delete(:enforce_available_locales)
+      enforce_available_locales = I18n.enforce_available_locales unless I18n.enforce_available_locales.nil?
+      I18n.enforce_available_locales = false
 
       app.config.i18n.each do |setting, value|
         case setting
@@ -49,6 +52,9 @@ module I18n
 
       init_fallbacks(fallbacks) if fallbacks && validate_fallbacks(fallbacks)
 
+      # Restore avalable locales check so it will take place from now on.
+      I18n.enforce_available_locales = enforce_available_locales
+
       reloader = ActiveSupport::FileUpdateChecker.new(I18n.load_path.dup){ I18n.reload! }
       app.reloaders << reloader
       ActionDispatch::Reloader.to_prepare { reloader.execute_if_updated }
diff --git a/activesupport/test/abstract_unit.rb b/activesupport/test/abstract_unit.rb
index 4600855998..1dfa3833f0 100644
--- a/activesupport/test/abstract_unit.rb
+++ b/activesupport/test/abstract_unit.rb
@@ -24,6 +24,9 @@ Thread.abort_on_exception = true
 # Show backtraces for deprecated behavior for quicker cleanup.
 ActiveSupport::Deprecation.debug = true
 
+# Disable available locale checks to avoid warnings running the test suite.
+I18n.enforce_available_locales = false
+
 # Skips the current run on Rubinius using Minitest::Assertions#skip
 def rubinius_skip(message = '')
   skip message if RUBY_ENGINE == 'rbx'