Merge pull request #42230 from ricardotk002/correct-null-flash-api

Use a regular flash object if session store is disabled

actionpack/lib/action_controller/metal/request_forgery_protection.rb

@@ -199,6 +199,10 @@ module ActionController #:nodoc:
             def exists?
               true
             end
+
+            def enabled?
+              false
+            end
           end
 
           class NullCookieJar < ActionDispatch::Cookies::CookieJar #:nodoc:

actionpack/lib/action_controller/test_case.rb

@@ -211,6 +211,10 @@ module ActionController
       @data.fetch(key.to_s, *args, &block)
     end
 
+    def enabled?
+      true
+    end
+
     private
       def load!
         @id

actionpack/lib/action_dispatch/middleware/flash.rb

@@ -45,7 +45,6 @@ module ActionDispatch
       # read a notice you put there or <tt>flash["notice"] = "hello"</tt>
       # to put a new one.
       def flash
-        return Flash::NullFlash unless session.respond_to?(:loaded?)
         flash = flash_hash
         return flash if flash
         self.flash = Flash::FlashHash.from_session_value(session["flash"])
@@ -60,16 +59,14 @@ module ActionDispatch
       end
 
       def commit_flash # :nodoc:
-        session    = self.session || {}
-        flash_hash = self.flash_hash
+        return unless session.enabled?
 
         if flash_hash && (flash_hash.present? || session.key?("flash"))
           session["flash"] = flash_hash.to_session_value
           self.flash = flash_hash.dup
         end
 
-        if (!session.respond_to?(:loaded?) || session.loaded?) && # reset_session uses {}, which doesn't implement #loaded?
-            session.key?("flash") && session["flash"].nil?
+        if session.loaded? && session.key?("flash") && session["flash"].nil?
           session.delete("flash")
         end
       end
@@ -80,20 +77,6 @@ module ActionDispatch
       end
     end
 
-    module NullFlash #:nodoc:
-      class << self
-        def []=(k, v); end
-
-        def [](k); end
-
-        def alert=(message); end
-
-        def notice=(message); end
-
-        def empty?; end
-      end
-    end
-
     class FlashNow #:nodoc:
       attr_accessor :flash
 

actionpack/test/controller/flash_test.rb

@@ -244,7 +244,7 @@ class FlashIntegrationTest < ActionDispatch::IntegrationTest
   SessionKey = "_myapp_session"
   Generator = ActiveSupport::CachingKeyGenerator.new(
     ActiveSupport::KeyGenerator.new("b3c631c314c0bbca50c1b2843150fe33", iterations: 1000)
- )
+  )
   Rotations = ActiveSupport::Messages::RotationConfiguration.new
   SIGNED_COOKIE_SALT = "signed cookie"