Add rake task to rename existing setting keys

spec/lib/tasks/settings_spec.rb

@@ -100,4 +100,79 @@ describe Setting do
 
   end
 
+
+  describe "#rename_setting_keys" do
+
+    let :run_rake_task do
+      Rake::Task["settings:rename_setting_keys"].reenable
+      Rake.application.invoke_task "settings:rename_setting_keys"
+    end
+
+    let :old_keys do
+      %w[map_latitude map_longitude map_zoom feature.debates feature.proposals feature.polls
+         feature.budgets feature.legislation per_page_code_head per_page_code_body
+         feature.homepage.widgets.feeds.proposals feature.homepage.widgets.feeds.debates
+         feature.homepage.widgets.feeds.processes]
+    end
+
+    let :new_keys do
+      %w[map.latitude map.longitude map.zoom process.debates process.proposals process.polls
+         process.budgets process.legislation html.per_page_code_head html.per_page_code_body
+         homepage.widgets.feeds.proposals homepage.widgets.feeds.debates
+         homepage.widgets.feeds.processes]
+    end
+
+    context "with existing old settings" do
+      it "rename all settings keys keeping the same value" do
+        Setting.destroy_all
+        old_keys.each { |old_key| Setting[old_key] = "old value" }
+
+        run_rake_task
+
+        new_keys.each do |new_key|
+          expect(Setting[new_key]).to eq "old value"
+        end
+
+        old_keys.each do |old_key|
+          expect(Setting.where(key: old_key)).not_to exist
+        end
+      end
+    end
+
+    context "without existing old settings" do
+      it "initializes all settings with null value" do
+        Setting.destroy_all
+
+        run_rake_task
+
+        new_keys.each do |new_key|
+          expect(Setting[new_key]).to eq nil
+        end
+
+        old_keys.each do |old_key|
+          expect(Setting.where(key: old_key)).not_to exist
+        end
+      end
+    end
+
+    context "with already existing new settings" do
+      it "does not change the value of the new settings even if the old setting exist" do
+        Setting.destroy_all
+        old_keys.each { |old_key| Setting[old_key] = "old value" }
+        new_keys.each { |new_key| Setting[new_key] = "new value" }
+
+        run_rake_task
+
+        new_keys.each do |new_key|
+          expect(Setting[new_key]).to eq "new value"
+        end
+
+        old_keys.each do |old_key|
+          expect(Setting.where(key: old_key)).not_to exist
+        end
+      end
+    end
+
+  end
+
 end