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, 4 insertions, 4 deletions

diff --git a/actionpack/lib/action_view/helpers/url_helper.rb b/actionpack/lib/action_view/helpers/url_helper.rb
index b5fc882e31..93f476926c 100644
--- a/actionpack/lib/action_view/helpers/url_helper.rb
+++ b/actionpack/lib/action_view/helpers/url_helper.rb
@@ -146,12 +146,12 @@ module ActionView
       #   create an HTML form and immediately submit the form for processing using
       #   the HTTP verb specified. Useful for having links perform a POST operation
       #   in dangerous actions like deleting a record (which search bots can follow
-      #   while spidering your site). Supported verbs are <tt>:post</tt>, <tt>:delete</tt> and <tt>:put</tt>.
+      #   while spidering your site). Supported verbs are <tt>:post</tt>, <tt>:delete</tt>, <tt>:patch</tt>, and <tt>:put</tt>.
       #   Note that if the user has JavaScript disabled, the request will fall back
       #   to using GET. If <tt>:href => '#'</tt> is used and the user has JavaScript
       #   disabled clicking the link will have no effect. If you are relying on the
       #   POST behavior, you should check for it in your controller's action by using
-      #   the request object's methods for <tt>post?</tt>, <tt>delete?</tt> or <tt>put?</tt>.
+      #   the request object's methods for <tt>post?</tt>, <tt>delete?</tt>, <tt>:patch</tt>, or <tt>put?</tt>.
       # * <tt>:remote => true</tt> - This will allow the unobtrusive JavaScript
       #   driver to make an Ajax request to the URL in question instead of following
       #   the link. The drivers each provide mechanisms for listening for the
@@ -272,7 +272,7 @@ module ActionView
       #
       # There are a few special +html_options+:
       # * <tt>:method</tt> - Symbol of HTTP verb. Supported verbs are <tt>:post</tt>, <tt>:get</tt>,
-      #   <tt>:delete</tt> and <tt>:put</tt>. By default it will be <tt>:post</tt>.
+      #   <tt>:delete</tt>, <tt>:patch</tt>, and <tt>:put</tt>. By default it will be <tt>:post</tt>.
       # * <tt>:disabled</tt> - If set to true, it will generate a disabled button.
       # * <tt>:confirm</tt> - This will use the unobtrusive JavaScript driver to
       #   prompt with the question specified. If the user accepts, the link is
@@ -329,7 +329,7 @@ module ActionView
         remote = html_options.delete('remote')
 
         method     = html_options.delete('method').to_s
-        method_tag = %w{put delete}.include?(method) ? method_tag(method) : ""
+        method_tag = %w{put patch delete}.include?(method) ? method_tag(method) : ""
 
         form_method  = method == 'get' ? 'get' : 'post'
         form_options = html_options.delete('form') || {}