Display a deprecation error if a remote git branch is specified

Capistrano 2.2 allowed you to do this:
set :branch,  "origin/release"

In capistrano 2.3, the correct syntax is now:
set :branch,  "release"

This change will cause capistrano to show a helpful error message for those upgraders who have been using the 'origin/release' syntax.

lib/capistrano/recipes/deploy/scm/git.rb

@@ -208,12 +208,13 @@ def log(from, to=nil)
         # Getting the actual commit id, in case we were passed a tag
         # or partial sha or something - it will return the sha if you pass a sha, too
         def query_revision(revision)
+          raise ArgumentError, "Deploying remote branches has been deprecated.  Specify the remote branch as a local branch for the git repository you're deploying from (ie: '#{revision.gsub('origin/', '')}' rather than '#{revision}')." if revision =~ /^origin\//
           return revision if revision =~ /^[0-9a-f]{40}$/
           command = scm('ls-remote', repository, revision)
           result = yield(command)
           revdata = result.split("\t")
           newrev = revdata[0]
-          raise "Unable to resolve revision for #{revision}" unless newrev =~ /^[0-9a-f]{40}$/
+          raise "Unable to resolve revision for '#{revision}' on repository '#{repository}'." unless newrev =~ /^[0-9a-f]{40}$/
           return newrev
         end
 

test/deploy/scm/git_test.rb

@@ -57,6 +57,12 @@ def test_query_revision
     assert_equal "d11006102c07c94e5d54dd0ee63dca825c93ed61", revision
   end
 
+  def test_query_revision_deprecation_error
+    assert_raise(ArgumentError) do
+      revision = @source.query_revision('origin/release') {}
+    end
+  end
+
   def test_command_should_be_backwards_compatible
     # 1.x version of this module used ":git", not ":scm_command"
     @config[:git] = "/srv/bin/git"