[BREAKING CHANGE: Convert empty string into nil for string-ish fields. Closes #2099

Setting empty string is unique-index unfriendly, and people should expect
clearing a string-ish field makes the column null.

Author: mshibuya

lib/rails_admin/config/fields/types/color.rb

@@ -1,12 +1,19 @@
 require 'rails_admin/config/fields/base'
+require 'rails_admin/config/fields/types/string'
 
 module RailsAdmin
   module Config
     module Fields
       module Types
-        class Color < RailsAdmin::Config::Fields::Base
+        class Color < RailsAdmin::Config::Fields::Types::String
           RailsAdmin::Config::Fields::Types.register(self)
 
+          register_instance_option :html_attributes do
+            {
+              required: required?,
+            }
+          end
+
           register_instance_option :pretty_value do
             bindings[:view].content_tag :strong, (value.presence || ' - '), style: "color: #{color}"
           end

lib/rails_admin/config/fields/types/hidden.rb

@@ -22,6 +22,10 @@ class Hidden < RailsAdmin::Config::Fields::Base
           def generic_help
             false
           end
+
+          def parse_input(params)
+            params[name] = params[name].presence if params.key?(name)
+          end
         end
       end
     end

lib/rails_admin/config/fields/types/string.rb

@@ -38,6 +38,10 @@ def generic_help
             text
           end
 
+          def parse_input(params)
+            params[name] = params[name].presence if params.key?(name)
+          end
+
           register_instance_option :partial do
             :form_field
           end

lib/rails_admin/config/fields/types/text.rb

@@ -16,6 +16,10 @@ class Text < RailsAdmin::Config::Fields::Base
             }
           end
 
+          def parse_input(params)
+            params[name] = params[name].presence if params.key?(name)
+          end
+
           register_instance_option :partial do
             :form_text
           end

spec/rails_admin/config/fields/types/action_text_spec.rb

@@ -2,4 +2,6 @@
 
 describe RailsAdmin::Config::Fields::Types::ActionText do
   it_behaves_like 'a generic field type', :action_text_field
+
+  it_behaves_like 'a string-ish field type', :action_text_field
 end if defined?(ActionText)

spec/rails_admin/config/fields/types/active_record_enum_spec.rb

@@ -0,0 +1,5 @@
+require 'spec_helper'
+
+describe RailsAdmin::Config::Fields::Types::ActiveRecordEnum, active_record: true do
+  it_behaves_like 'a generic field type', :string_enum_field
+end

spec/rails_admin/config/fields/types/ck_editor_spec.rb

@@ -2,4 +2,6 @@
 
 describe RailsAdmin::Config::Fields::Types::CKEditor do
   it_behaves_like 'a generic field type', :text_field, :ck_editor
+
+  it_behaves_like 'a string-ish field type', :text_field, :ck_editor
 end

spec/rails_admin/config/fields/types/code_mirror_spec.rb

@@ -2,4 +2,6 @@
 
 describe RailsAdmin::Config::Fields::Types::CodeMirror do
   it_behaves_like 'a generic field type', :text_field, :code_mirror
+
+  it_behaves_like 'a string-ish field type', :text_field, :code_mirror
 end

spec/rails_admin/config/fields/types/color_spec.rb

@@ -2,4 +2,6 @@
 
 describe RailsAdmin::Config::Fields::Types::Color do
   it_behaves_like 'a generic field type', :string_field, :color
+
+  it_behaves_like 'a string-ish field type', :string_field, :color
 end

spec/rails_admin/config/fields/types/hidden_spec.rb

@@ -2,4 +2,6 @@
 
 describe RailsAdmin::Config::Fields::Types::Hidden do
   it_behaves_like 'a generic field type', :integer_field, :hidden
+
+  it_behaves_like 'a string-ish field type', :string_field, :hidden
 end