Allow the use of callable objects as group methods for grouped selects.

Replaced the uses of `group.send(...)` in `option_groups_from_collection_for_select`
by calls to `value_for_collection(group, ...)`, allowing the use of
procs, lambdas and other callable objects as parameters.

1 files changed, 10 insertions, 4 deletions

diff --git a/actionview/lib/action_view/helpers/form_options_helper.rb b/actionview/lib/action_view/helpers/form_options_helper.rb
index 02a44477c1..a46741f661 100644
--- a/actionview/lib/action_view/helpers/form_options_helper.rb
+++ b/actionview/lib/action_view/helpers/form_options_helper.rb
@@ -214,9 +214,15 @@ module ActionView
       # * +method+ - The attribute of +object+ corresponding to the select tag
       # * +collection+ - An array of objects representing the <tt><optgroup></tt> tags.
       # * +group_method+ - The name of a method which, when called on a member of +collection+, returns an
-      #   array of child objects representing the <tt><option></tt> tags.
+      #   array of child objects representing the <tt><option></tt> tags. It can also be any object that responds
+      #   to +call+, such as a +proc+, that will be called for each member of the +collection+ to retrieve the
+      #   value.
+
       # * +group_label_method+ - The name of a method which, when called on a member of +collection+, returns a
-      #   string to be used as the +label+ attribute for its <tt><optgroup></tt> tag.
+      #   string to be used as the +label+ attribute for its <tt><optgroup></tt> tag. It can also be any object
+      #   that responds to +call+, such as a +proc+, that will be called for each member of the +collection+ to
+      #   retrieve the label.
+
       # * +option_key_method+ - The name of a method which, when called on a child object of a member of
       #   +collection+, returns a value to be used as the +value+ attribute for its <tt><option></tt> tag.
       # * +option_value_method+ - The name of a method which, when called on a child object of a member of
@@ -457,9 +463,9 @@ module ActionView
       def option_groups_from_collection_for_select(collection, group_method, group_label_method, option_key_method, option_value_method, selected_key = nil)
         collection.map do |group|
           option_tags = options_from_collection_for_select(
-            group.send(group_method), option_key_method, option_value_method, selected_key)
+            value_for_collection(group, group_method), option_key_method, option_value_method, selected_key)
 
-          content_tag("optgroup".freeze, option_tags, label: group.send(group_label_method))
+          content_tag("optgroup".freeze, option_tags, label: value_for_collection(group, group_label_method))
         end.join.html_safe
       end