Add checkbox_style config, to opt for :inline or :nested

lib/generators/simple_form/templates/config/initializers/simple_form.rb.tt

@@ -138,6 +138,11 @@ SimpleForm.setup do |config|
   # You can define the class to use on all labels. Default is nil.
   # config.label_class = nil
 
+  # Define the way to render checkboxes with labels. Defaults to :inline.
+  #   :inline => input + label
+  #   :nested => label > input
+  # config.checkbox_style = :inline
+
   # You can define the class to use on all forms. Default is simple_form.
   # config.form_class = :simple_form
 

lib/simple_form.rb

@@ -61,6 +61,12 @@ module SimpleForm
   mattr_accessor :label_class
   @@label_class = nil
 
+  # Define the way to render checkboxes with labels. Defaults to :inline.
+  #   :inline => input + label
+  #   :nested => label > input
+  mattr_accessor :checkbox_style
+  @@checkbox_style = :inline
+
   # You can define the class to use on all forms. Default is simple_form.
   mattr_accessor :form_class
   @@form_class = :simple_form

lib/simple_form/inputs/boolean_input.rb

@@ -6,11 +6,21 @@ module SimpleForm
       end
 
       def label_input
-        input + (options[:label] == false ? "" : label)
+        if options[:label] == false
+          input
+        elsif nested_style?
+          @builder.label(attribute_name) { input }
+        else
+          input + label
+        end
       end
 
       private
 
+      def nested_style?
+        options[:checkbox_style] || SimpleForm.checkbox_style == :nested
+      end
+
       # Booleans are not required by default because in most of the cases
       # it makes no sense marking them as required. The only exception is
       # Terms of Use usually presented at most sites sign up screen.
@@ -19,4 +29,4 @@ module SimpleForm
       end
     end
   end
-end
+end

test/inputs/boolean_input_test.rb

@@ -5,6 +5,40 @@ class BooleanInputTest < ActionView::TestCase
   test 'input should generate a checkbox by default for boolean attributes' do
     with_input_for @user, :active, :boolean
     assert_select 'input[type=checkbox].boolean#user_active'
+    assert_select 'label.boolean.optional', 'Active'
+  end
+
+  test 'input does not generate the label with the checkbox when label option is false' do
+    with_input_for @user, :active, :boolean, :label => false
+    assert_select 'input[type=checkbox].boolean#user_active'
+    assert_no_select 'label'
+  end
+
+  test 'input uses inline checkbox style by default' do
+    with_input_for @user, :active, :boolean
     assert_select 'input.boolean + label.boolean.optional'
+    assert_no_select 'label > input'
+  end
+
+  test 'input allows changing default checkbox style config to nested, generating a default label' do
+    swap SimpleForm, :checkbox_style => :nested do
+      with_input_for @user, :active, :boolean
+      assert_select 'label > input.boolean'
+      assert_no_select 'label.boolean'
+    end
+  end
+
+  test 'input accepts changing checkbox style through given options' do
+    with_input_for @user, :active, :boolean, :checkbox_style => :nested
+    assert_select 'label > input.boolean'
+    assert_no_select 'label.boolean'
+  end
+
+  test 'input with nested style allows disabling label' do
+    swap SimpleForm, :checkbox_style => :nested do
+      with_input_for @user, :active, :boolean, :label => false
+      assert_select 'input.boolean'
+      assert_no_select 'label'
+    end
   end
 end