1 files changed, 47 insertions, 0 deletions
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..dc019db6ac
--- /dev/null
+++ b/actionpack/lib/action_dispatch/testing/assertion_response.rb
@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+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.
+  class AssertionResponse
+    attr_reader :code, :name
+
+    GENERIC_RESPONSE_CODES = { # :nodoc:
+      success: "2XX",
+      missing: "404",
+      redirect: "3XX",
+      error: "5XX"
+    }
+
+    # Accepts a specific response status code as an Integer (404) or String
+    # ('404') or a response status range as a Symbol pseudo-code (:success,
+    # indicating any 200-299 status code).
+    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