add helpers for dealing with status codes

lib/sinatra/base.rb

@@ -310,6 +310,37 @@ module Sinatra
       request.referer
     end
 
+    # whether or not the status is set to 1xx
+    def informational?
+      status.between? 100, 199
+    end
+
+    # whether or not the status is set to 2xx
+    def success?
+      status.between? 200, 299
+    end
+
+    # whether or not the status is set to 3xx
+    def redirect?
+      status.between? 300, 399
+    end
+
+    # whether or not the status is set to 4xx
+    def client_error?
+      status.between? 400, 499
+    end
+
+    # whether or not the status is set to 5xx
+    def server_error?
+      status.between? 500, 599
+    end
+
+    # whether or not the status is set to 404
+    def not_found?
+      status == 404
+    end
+
+
     private
 
     # Ruby 1.8 has no #to_time method.

test/helpers_test.rb

@@ -6,19 +6,113 @@ class HelpersTest < Test::Unit::TestCase
     assert true
   end
 
+  def status_app(code, &block)
+    block ||= proc { }
+    mock_app do
+      get '/' do
+        status code
+        instance_eval(&block).inspect
+      end
+    end
+    get '/'
+  end
+
   describe 'status' do
-    setup do
-      mock_app {
-        get '/' do
-          status 207
-          nil
-        end
-      }
+    it 'sets the response status code' do
+      status_app 207
+      assert_equal 207, response.status
+    end
+  end
+
+  describe 'not_found?' do
+    it 'is true for status == 404' do
+      status_app(404) { not_found? }
+      assert_body 'true'
     end
 
-    it 'sets the response status code' do
-      get '/'
-      assert_equal 207, response.status
+    it 'is false for status > 404' do
+      status_app(405) { not_found? }
+      assert_body 'false'
+    end
+
+    it 'is false for status < 404' do
+      status_app(403) { not_found? }
+      assert_body 'false'
+    end
+  end
+
+  describe 'informational?' do
+    it 'is true for 1xx status' do
+      status_app(100 + rand(100)) { informational? }
+      assert_body 'true'
+    end
+
+    it 'is false for status > 199' do
+      status_app(200 + rand(400)) { informational? }
+      assert_body 'false'
+    end
+  end
+
+  describe 'success?' do
+    it 'is true for 2xx status' do
+      status_app(200 + rand(100)) { success? }
+      assert_body 'true'
+    end
+
+    it 'is false for status < 200' do
+      status_app(100 + rand(100)) { success? }
+      assert_body 'false'
+    end
+
+    it 'is false for status > 299' do
+      status_app(300 + rand(300)) { success? }
+      assert_body 'false'
+    end
+  end
+
+  describe 'redirect?' do
+    it 'is true for 3xx status' do
+      status_app(300 + rand(100)) { redirect? }
+      assert_body 'true'
+    end
+
+    it 'is false for status < 300' do
+      status_app(200 + rand(100)) { redirect? }
+      assert_body 'false'
+    end
+
+    it 'is false for status > 399' do
+      status_app(400 + rand(200)) { redirect? }
+      assert_body 'false'
+    end
+  end
+
+  describe 'client_error?' do
+    it 'is true for 4xx status' do
+      status_app(400 + rand(100)) { client_error? }
+      assert_body 'true'
+    end
+
+    it 'is false for status < 400' do
+      status_app(200 + rand(200)) { client_error? }
+      assert_body 'false'
+    end
+
+    it 'is false for status > 499' do
+      status_app(500 + rand(100)) { client_error? }
+      assert_body 'false'
+    end
+  end
+
+  describe 'server_error?' do
+    it 'is true for 5xx status' do
+      status_app(500 + rand(100)) { server_error? }
+      assert_body 'true'
+    end
+
+    it 'is false for status < 500' do
+      status_app(200 + rand(300)) { server_error? }
+      assert_body 'false'
     end
   end