1 files changed, 50 insertions, 25 deletions

diff --git a/actionpack/lib/action_dispatch/middleware/flash.rb b/actionpack/lib/action_dispatch/middleware/flash.rb
index 89003e7a5e..59639a010e 100644
--- a/actionpack/lib/action_dispatch/middleware/flash.rb
+++ b/actionpack/lib/action_dispatch/middleware/flash.rb
@@ -1,3 +1,5 @@
+require 'active_support/core_ext/hash/keys'
+
 module ActionDispatch
   class Request < Rack::Request
     # Access the contents of the flash. Use <tt>flash["notice"]</tt> to
@@ -8,7 +10,7 @@ module ActionDispatch
     end
   end
 
-  # The flash provides a way to pass temporary objects between actions. Anything you place in the flash will be exposed
+  # The flash provides a way to pass temporary primitive-types (String, Array, Hash) between actions. Anything you place in the flash will be exposed
   # to the very next action and then cleared out. This is a great way of doing notices and alerts, such as a create
   # action that sets <tt>flash[:notice] = "Post successfully created"</tt> before redirecting to a display action that can
   # then expose the flash to its template. Actually, that exposure is automatically done.
@@ -35,8 +37,11 @@ module ActionDispatch
   #   flash.alert = "You must be logged in"
   #   flash.notice = "Post successfully created"
   #
-  # This example just places a string in the flash, but you can put any object in there. And of course, you can put as
-  # many as you like at a time too. Just remember: They'll be gone by the time the next action has been performed.
+  # This example places a string in the flash. And of course, you can put as many as you like at a time too. If you want to pass
+  # non-primitive types, you will have to handle that in your application. Example: To show messages with links, you will have to
+  # use sanitize helper.
+  #
+  # Just remember: They'll be gone by the time the next action has been performed.
   #
   # See docs on the FlashHash class for more details about the flash.
   class Flash
@@ -50,13 +55,14 @@ module ActionDispatch
       end
 
       def []=(k, v)
+        k = k.to_s
         @flash[k] = v
         @flash.discard(k)
         v
       end
 
       def [](k)
-        @flash[k]
+        @flash[k.to_s]
       end
 
       # Convenience accessor for <tt>flash.now[:alert]=</tt>.
@@ -73,27 +79,36 @@ module ActionDispatch
     class FlashHash
       include Enumerable
 
-      def self.from_session_value(value)
-        flash = case value
-                when FlashHash # Rails 3.1, 3.2
-                  new(value.instance_variable_get(:@flashes), value.instance_variable_get(:@used))
-                when Hash # Rails 4.0
-                  new(value['flashes'], value['discard'])
-                else
-                  new
-                end
-
-        flash.tap(&:sweep)
+      def self.from_session_value(value) #:nodoc:
+        case value
+        when FlashHash # Rails 3.1, 3.2
+          flashes = value.instance_variable_get(:@flashes)
+          if discard = value.instance_variable_get(:@used)
+            flashes.except!(*discard)
+          end
+          new(flashes, flashes.keys)
+        when Hash # Rails 4.0
+          flashes = value['flashes']
+          if discard = value['discard']
+            flashes.except!(*discard)
+          end
+          new(flashes, flashes.keys)
+        else
+          new
+        end
       end
 
-      def to_session_value
-        return nil if empty?
-        {'discard' => @discard.to_a, 'flashes' => @flashes}
+      # Builds a hash containing the flashes to keep for the next request.
+      # If there are none to keep, returns nil.
+      def to_session_value #:nodoc:
+        flashes_to_keep = @flashes.except(*@discard)
+        return nil if flashes_to_keep.empty?
+        {'flashes' => flashes_to_keep}
       end
 
       def initialize(flashes = {}, discard = []) #:nodoc:
-        @discard = Set.new(discard)
-        @flashes = flashes
+        @discard = Set.new(stringify_array(discard))
+        @flashes = flashes.stringify_keys
         @now     = nil
       end
 
@@ -106,17 +121,18 @@ module ActionDispatch
       end
 
       def []=(k, v)
+        k = k.to_s
         @discard.delete k
         @flashes[k] = v
       end
 
       def [](k)
-        @flashes[k]
+        @flashes[k.to_s]
       end
 
       def update(h) #:nodoc:
-        @discard.subtract h.keys
-        @flashes.update h
+        @discard.subtract stringify_array(h.keys)
+        @flashes.update h.stringify_keys
         self
       end
 
@@ -125,10 +141,11 @@ module ActionDispatch
       end
 
       def key?(name)
-        @flashes.key? name
+        @flashes.key? name.to_s
       end
 
       def delete(key)
+        key = key.to_s
         @discard.delete key
         @flashes.delete key
         self
@@ -155,7 +172,7 @@ module ActionDispatch
 
       def replace(h) #:nodoc:
         @discard.clear
-        @flashes.replace h
+        @flashes.replace h.stringify_keys
         self
       end
 
@@ -186,6 +203,7 @@ module ActionDispatch
       #    flash.keep            # keeps the entire flash
       #    flash.keep(:notice)   # keeps only the "notice" entry, the rest of the flash is discarded
       def keep(k = nil)
+        k = k.to_s if k
         @discard.subtract Array(k || keys)
         k ? self[k] : self
       end
@@ -195,6 +213,7 @@ module ActionDispatch
       #     flash.discard              # discard the entire flash at the end of the current action
       #     flash.discard(:warning)    # discard only the "warning" entry at the end of the current action
       def discard(k = nil)
+        k = k.to_s if k
         @discard.merge Array(k || keys)
         k ? self[k] : self
       end
@@ -231,6 +250,12 @@ module ActionDispatch
       def now_is_loaded?
         @now
       end
+
+      def stringify_array(array)
+        array.map do |item|
+          item.kind_of?(Symbol) ? item.to_s : item
+        end
+      end
     end
 
     def initialize(app)