Add a hidden field on the collection_radio_buttons

This will avoid a error be raised when the only input on the form is the
`collection_radio_buttons`.

2 files changed, 44 insertions, 4 deletions

diff --git a/actionview/test/template/form_collections_helper_test.rb b/actionview/test/template/form_collections_helper_test.rb
index b193d387c3..32471b1640 100644
--- a/actionview/test/template/form_collections_helper_test.rb
+++ b/actionview/test/template/form_collections_helper_test.rb
@@ -198,6 +198,41 @@ class FormCollectionsHelperTest < ActionView::TestCase
     assert_select 'input[type=radio][value=false][checked=checked]'
   end
 
+  test 'collection radio buttons generates only one hidden field for the entire collection, to ensure something will be sent back to the server when posting an empty collection' do
+    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+    with_collection_radio_buttons :user, :category_ids, collection, :id, :name
+
+    assert_select "input[type=hidden][name='user[category_ids][]'][value='']", count: 1
+  end
+
+  test 'collection radio buttons generates a hidden field using the given :name in :html_options' do
+    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+    with_collection_radio_buttons :user, :category_ids, collection, :id, :name, {}, { name: "user[other_category_ids][]" }
+
+    assert_select "input[type=hidden][name='user[other_category_ids][]'][value='']", count: 1
+  end
+
+  test 'collection radio buttons generates a hidden field with index if it was provided' do
+    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+    with_collection_radio_buttons :user, :category_ids, collection, :id, :name, { index: 322 }
+
+    assert_select "input[type=hidden][name='user[322][category_ids][]'][value='']", count: 1
+  end
+
+  test 'collection radio buttons does not generate a hidden field if include_hidden option is false' do
+    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+    with_collection_radio_buttons :user, :category_ids, collection, :id, :name, include_hidden: false
+
+    assert_select "input[type=hidden][name='user[category_ids][]'][value='']", count: 0
+  end
+
+  test 'collection radio buttons does not generate a hidden field if include_hidden option is false with key as string' do
+    collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
+    with_collection_radio_buttons :user, :category_ids, collection, :id, :name, 'include_hidden' => false
+
+    assert_select "input[type=hidden][name='user[category_ids][]'][value='']", count: 0
+  end
+
   # COLLECTION CHECK BOXES
   test 'collection check boxes accepts a collection and generate a series of checkboxes for value method' do
     collection = [Category.new(1, 'Category 1'), Category.new(2, 'Category 2')]
diff --git a/actionview/test/template/form_helper_test.rb b/actionview/test/template/form_helper_test.rb
index 77c660d450..2fc381c93d 100644
--- a/actionview/test/template/form_helper_test.rb
+++ b/actionview/test/template/form_helper_test.rb
@@ -1596,7 +1596,8 @@ class FormHelperTest < ActionView::TestCase
       "<input id='post_active_true' name='post[active]' type='radio' value='true' />" +
       "<label for='post_active_true'>true</label>" +
       "<input checked='checked' id='post_active_false' name='post[active]' type='radio' value='false' />" +
-      "<label for='post_active_false'>false</label>"
+      "<label for='post_active_false'>false</label>" +
+      "<input type='hidden' name='post[active][]' value='' />"
     end
 
     assert_dom_equal expected, output_buffer
@@ -1619,7 +1620,8 @@ class FormHelperTest < ActionView::TestCase
       "true</label>" +
       "<label for='post_active_false'>"+
       "<input checked='checked' id='post_active_false' name='post[active]' type='radio' value='false' />" +
-      "false</label>"
+      "false</label>" +
+      "<input type='hidden' name='post[active][]' value='' />"
     end
 
     assert_dom_equal expected, output_buffer
@@ -1645,6 +1647,7 @@ class FormHelperTest < ActionView::TestCase
       "<label for='post_active_false'>"+
       "<input checked='checked' id='post_active_false' name='post[active]' type='radio' value='false' />" +
       "false</label>"+
+      "<input type='hidden' name='post[active][]' value='' />" +
       "<input id='post_id' name='post[id]' type='hidden' value='1' />"
     end
 
@@ -1663,7 +1666,8 @@ class FormHelperTest < ActionView::TestCase
       "<input id='foo_post_active_true' name='post[active]' type='radio' value='true' />" +
       "<label for='foo_post_active_true'>true</label>" +
       "<input checked='checked' id='foo_post_active_false' name='post[active]' type='radio' value='false' />" +
-      "<label for='foo_post_active_false'>false</label>"
+      "<label for='foo_post_active_false'>false</label>" +
+      "<input type='hidden' name='post[active][]' value='' />"
     end
 
     assert_dom_equal expected, output_buffer
@@ -1681,7 +1685,8 @@ class FormHelperTest < ActionView::TestCase
       "<input id='post_1_active_true' name='post[1][active]' type='radio' value='true' />" +
       "<label for='post_1_active_true'>true</label>" +
       "<input checked='checked' id='post_1_active_false' name='post[1][active]' type='radio' value='false' />" +
-      "<label for='post_1_active_false'>false</label>"
+      "<label for='post_1_active_false'>false</label>" +
+      "<input type='hidden' name='post[1][active][]' value='' />"
     end
 
     assert_dom_equal expected, output_buffer