Merge pull request #26962 from rails/fix-3-2-stable-on-ruby-2-3

Fix Rails 3-2-stable on Ruby 2.3.1

4 files changed, 18 insertions, 4 deletions

diff --git a/actionpack/lib/abstract_controller/helpers.rb b/actionpack/lib/abstract_controller/helpers.rb
index 77cc4c07d9..7a9055a679 100644
--- a/actionpack/lib/abstract_controller/helpers.rb
+++ b/actionpack/lib/abstract_controller/helpers.rb
@@ -12,6 +12,15 @@ module AbstractController
       self._helper_methods = Array.new
     end
 
+    class MissingHelperError < LoadError
+      def initialize(error, path)
+        @error = error
+        @path  = "helpers/#{path}.rb"
+        set_backtrace error.backtrace
+        super("Missing helper file helpers/%s.rb" % path)
+      end
+    end
+
     module ClassMethods
       # When a class is inherited, wrap its helper module in a new module.
       # This ensures that the parent class's module can be changed
@@ -132,7 +141,11 @@ module AbstractController
           case arg
           when String, Symbol
             file_name = "#{arg.to_s.underscore}_helper"
-            require_dependency(file_name, "Missing helper file helpers/%s.rb")
+            begin
+              require_dependency(file_name)
+            rescue LoadError => e
+              raise MissingHelperError.new(e, file_name)
+            end
             file_name.camelize.constantize
           when Module
             arg
diff --git a/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_include_tag.rb b/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_include_tag.rb
index 05d5f1870a..edfc374b3b 100644
--- a/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_include_tag.rb
+++ b/actionpack/lib/action_view/helpers/asset_tag_helpers/asset_include_tag.rb
@@ -47,7 +47,7 @@ module ActionView
           if concat || (config.perform_caching && cache)
             joined_name = (cache == true ? "all" : cache) + ".#{extension}"
             joined_path = File.join((joined_name[/^#{File::SEPARATOR}/] ? config.assets_dir : custom_dir), joined_name)
-            unless config.perform_caching && File.exists?(joined_path)
+            unless config.perform_caching && File.exist?(joined_path)
               write_asset_file_contents(joined_path, compute_paths(sources, recursive))
             end
             asset_tag(joined_name, options)
diff --git a/actionpack/lib/action_view/template.rb b/actionpack/lib/action_view/template.rb
index e67e52cc76..069ac4e761 100644
--- a/actionpack/lib/action_view/template.rb
+++ b/actionpack/lib/action_view/template.rb
@@ -323,7 +323,8 @@ module ActionView
       end
 
       def locals_code #:nodoc:
-        @locals.map { |key| "#{key} = local_assigns[:#{key}];" }.join
+        # Double assign to suppress the dreaded 'assigned but unused variable' warning
+        @locals.map { |key| "#{key} = #{key} = local_assigns[:#{key}];" }.join
       end
 
       def method_name #:nodoc:
diff --git a/actionpack/lib/sprockets/helpers/rails_helper.rb b/actionpack/lib/sprockets/helpers/rails_helper.rb
index 243c2e5e50..6712aefb2d 100644
--- a/actionpack/lib/sprockets/helpers/rails_helper.rb
+++ b/actionpack/lib/sprockets/helpers/rails_helper.rb
@@ -163,7 +163,7 @@ module Sprockets
             source
           elsif source_ext.blank?
             "#{source}.#{ext}"
-          elsif File.exists?(source) || exact_match_present?(source)
+          elsif File.exist?(source) || exact_match_present?(source)
             source
           else
             "#{source}.#{ext}"