Add both HTTP Response Code and Type to assertion messages

Also, refactor logic to convert between symbol and response code,
via the AssertionResponse class

3 files changed, 64 insertions, 14 deletions

diff --git a/actionpack/lib/action_dispatch.rb b/actionpack/lib/action_dispatch.rb
index 7bc6575ccd..1e4df07d6e 100644
--- a/actionpack/lib/action_dispatch.rb
+++ b/actionpack/lib/action_dispatch.rb
@@ -95,6 +95,7 @@ module ActionDispatch
     autoload :TestProcess
     autoload :TestRequest
     autoload :TestResponse
+    autoload :AssertionResponse
   end
 end
 
diff --git a/actionpack/lib/action_dispatch/testing/assertion_response.rb b/actionpack/lib/action_dispatch/testing/assertion_response.rb
new file mode 100644
index 0000000000..3fb81ff083
--- /dev/null
+++ b/actionpack/lib/action_dispatch/testing/assertion_response.rb
@@ -0,0 +1,49 @@
+module ActionDispatch
+  # This is a class that abstracts away an asserted response.
+  # It purposely does not inherit from Response, because it doesn't need it.
+  # That means it does not have headers or a body.
+  #
+  # As an input to the initializer, we take a Fixnum, a String, or a Symbol.
+  # If it's a Fixnum or String, we figure out what its symbolized name.
+  # If it's a Symbol, we figure out what its corresponding code is.
+  # The resulting code will be a Fixnum, for real HTTP codes, and it will
+  # be a String for the pseudo-HTTP codes, such as:
+  #   :success, :missing, :redirect and :error
+  class AssertionResponse
+    attr_reader :code, :name
+
+    GENERIC_RESPONSE_CODES = { # :nodoc:
+      success: "2XX",
+      missing: "404",
+      redirect: "3XX",
+      error: "5XX"
+    }
+
+    def initialize(code_or_name)
+      if code_or_name.is_a?(Symbol)
+        @name = code_or_name
+        @code = code_from_name(code_or_name)
+      else
+        @name = name_from_code(code_or_name)
+        @code = code_or_name
+      end
+
+      raise ArgumentError, "Invalid response name: #{name}" if @code.nil?
+      raise ArgumentError, "Invalid response code: #{code}" if @name.nil?
+    end
+
+    def code_and_name
+      "#{code}: #{name}"
+    end
+
+    private
+
+    def code_from_name(name)
+      GENERIC_RESPONSE_CODES[name] || Rack::Utils::SYMBOL_TO_STATUS_CODE[name]
+    end
+
+    def name_from_code(code)
+      GENERIC_RESPONSE_CODES.invert[code] || Rack::Utils::HTTP_STATUS_CODES[code]
+    end
+  end
+end
diff --git a/actionpack/lib/action_dispatch/testing/assertions/response.rb b/actionpack/lib/action_dispatch/testing/assertions/response.rb
index c138660a21..cd55b7d975 100644
--- a/actionpack/lib/action_dispatch/testing/assertions/response.rb
+++ b/actionpack/lib/action_dispatch/testing/assertions/response.rb
@@ -1,4 +1,3 @@
-
 module ActionDispatch
   module Assertions
     # A small suite of assertions that test responses from \Rails applications.
@@ -29,18 +28,10 @@ module ActionDispatch
       def assert_response(type, message = nil)
         message ||= generate_response_message(type)
 
-        if Symbol === type
-          if [:success, :missing, :redirect, :error].include?(type)
-            assert @response.send(RESPONSE_PREDICATES[type]), message
-          else
-            code = Rack::Utils::SYMBOL_TO_STATUS_CODE[type]
-            if code.nil?
-              raise ArgumentError, "Invalid response type :#{type}"
-            end
-            assert_equal code, @response.response_code, message
-          end
+        if RESPONSE_PREDICATES.keys.include?(type)
+          assert @response.send(RESPONSE_PREDICATES[type]), message
         else
-          assert_equal type, @response.response_code, message
+          assert_equal AssertionResponse.new(type).code, @response.response_code, message
         end
       end
 
@@ -85,8 +76,9 @@ module ActionDispatch
           end
         end
 
-        def generate_response_message(type, code = @response.response_code)
-          "Expected response to be a <#{type}>, but was a <#{code}>"
+        def generate_response_message(expected, actual = @response.response_code)
+          "Expected response to be a <#{code_with_name(expected)}>,"\
+          " but was a <#{code_with_name(actual)}>"
           .concat location_if_redirected
         end
 
@@ -95,6 +87,14 @@ module ActionDispatch
           location = normalize_argument_to_redirection(@response.location)
           " redirect to <#{location}>"
         end
+
+        def code_with_name(code_or_name)
+          if RESPONSE_PREDICATES.values.include?("#{code_or_name}?".to_sym)
+            code_or_name = RESPONSE_PREDICATES.invert["#{code_or_name}?".to_sym]
+          end
+
+          AssertionResponse.new(code_or_name).code_and_name
+        end
     end
   end
 end