Add config.default_method_for_update to support PATCH

PATCH is the correct HTML verb to map to the #update action. The
semantics for PATCH allows for partial updates, whereas PUT requires a
complete replacement.

Changes:
* adds config.default_method_for_update you can set to :patch
* optionally use PATCH instead of PUT in resource routes and forms
* adds the #patch verb to routes to detect PATCH requests
* adds #patch? to Request
* changes documentation and comments to indicate support for PATCH

This change maintains complete backwards compatibility by keeping :put
as the default for config.default_method_for_update.

1 files changed, 8 insertions, 4 deletions

diff --git a/activeresource/test/cases/format_test.rb b/activeresource/test/cases/format_test.rb
index 30342ecc74..315f9db1eb 100644
--- a/activeresource/test/cases/format_test.rb
+++ b/activeresource/test/cases/format_test.rb
@@ -11,11 +11,15 @@ class FormatTest < ActiveSupport::TestCase
   end
 
   def test_http_format_header_name
-    header_name = ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[:get]
-    assert_equal 'Accept', header_name
+    [:get, :head].each do |verb|
+      header_name = ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[verb]
+      assert_equal 'Accept', header_name
+    end
 
-    headers_names = [ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[:put], ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[:post]]
-    headers_names.each{ |name| assert_equal 'Content-Type', name }
+    [:patch, :put, :post].each do |verb|
+      header_name = ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[verb]
+      assert_equal 'Content-Type', header_name
+    end
   end
 
   def test_formats_on_single_element