Remove more warnings on AP.

actionpack/lib/action_dispatch/middleware/session/abstract_store.rb

@@ -102,8 +102,8 @@ def loaded?
 
         def destroy
           clear
-          @by.send(:destroy, @env) if @by
-          @env[ENV_SESSION_OPTIONS_KEY][:id] = nil if @env && @env[ENV_SESSION_OPTIONS_KEY]
+          @by.send(:destroy, @env) if defined?(@by) && @by
+          @env[ENV_SESSION_OPTIONS_KEY][:id] = nil if defined?(@env) && @env && @env[ENV_SESSION_OPTIONS_KEY]
           @loaded = false
         end
 

actionpack/lib/action_dispatch/testing/assertions/selector.rb

@@ -67,7 +67,7 @@ def css_select(*args)
           arg = args.shift
         elsif arg == nil
           raise ArgumentError, "First argument is either selector or element to select, but nil found. Perhaps you called assert_select with an element that does not exist?"
-        elsif @selected
+        elsif defined?(@selected) && @selected
           matches = []
 
           @selected.each do |selected|
@@ -443,6 +443,7 @@ def assert_select_rjs(*args, &block)
           assert_block("") { true } # to count the assertion
           if block_given? && !([:remove, :show, :hide, :toggle].include? rjs_type)
             begin
+              @selected ||= nil
               in_scope, @selected = @selected, matches
               yield matches
             ensure

actionpack/test/controller/filters_test.rb

@@ -669,7 +669,7 @@ def test_conditional_skipping_of_filters
     assert_equal %w( ensure_login find_user ), assigns["ran_filter"]
 
     test_process(ConditionalSkippingController, "login")
-    assert_nil @controller.instance_variable_get("@ran_after_filter")
+    assert !@controller.instance_variable_defined?("@ran_after_filter")
     test_process(ConditionalSkippingController, "change_password")
     assert_equal %w( clean_up ), @controller.instance_variable_get("@ran_after_filter")
   end