Change not to show source when

There is no difference between config files

app/assets/stylesheets/common.css.scss

@@ -177,3 +177,11 @@ label {
     background-color: #dfd;
   }
 }
+
+.frame-corner-radius {
+  border: 1px solid #ddd;
+  padding:10px 10px;
+  border-radius: 3px;
+  margin: 10px 0px;
+}
+

app/controllers/concerns/setting_history_concern.rb

@@ -10,7 +10,10 @@ module SettingHistoryConcern
   def show
     current = @fluentd.agent.config
     target = @backup_file.content
-    @sdiff = Diff::LCS.sdiff(current.split("\n").map(&:rstrip), target.split("\n").map(&:rstrip)) if target
+    if target
+      @sdiff = Diff::LCS.sdiff(current.split("\n").map(&:rstrip), target.split("\n").map(&:rstrip))
+      @changed = @sdiff.any? { |context_change| context_change.changed? }
+    end
   end
 
   def reuse

app/views/shared/settings/_diff.html.erb

@@ -1,15 +1,21 @@
-<pre>
-<% @sdiff.each do |diff| %>
-<% case diff.action %>
-<% when "=" %>
-<span class="stay"><%= diff.new_element %></span>
-<% when "!" %>
-<span class="deleted">- <%= diff.old_element %></span>
-<span class="added">+ <%= diff.new_element %></span>
-<% when "-" %>
-<span class="deleted">- <%= diff.old_element %></span>
-<% when "+" %>
-<span class="added">+ <%= diff.new_element %></span>
+<% if @changed %>
+  <pre>
+  <% @sdiff.each do |diff| %>
+  <% case diff.action %>
+  <% when "=" %>
+  <span class="stay"><%= diff.new_element %></span>
+  <% when "!" %>
+  <span class="deleted">- <%= diff.old_element %></span>
+  <span class="added">+ <%= diff.new_element %></span>
+  <% when "-" %>
+  <span class="deleted">- <%= diff.old_element %></span>
+  <% when "+" %>
+  <span class="added">+ <%= diff.new_element %></span>
+  <% end %>
+  <% end %>
+  </pre>
+<% else %>
+  <div class="frame-corner-radius">
+   <%= t('messages.no_diff') %>
+  </div>
 <% end %>
-<% end %>
-</pre>

config/locales/translation_en.yml

@@ -14,6 +14,7 @@ en:
     config_successfully_copied: "Config has been copied successfully. Please restart %{brand} to use the new config"
     note_updating_success: "Note successfully updated."
     dryrun_is_passed: config test passed
+    no_diff: There is no difference in files.
 
   terms: &terms
     name: Name

config/locales/translation_ja.yml

@@ -14,6 +14,7 @@ ja:
     config_successfully_copied: "設定をコピーしました。反映させるには、 %{brand}を再起動してください。"
     note_updating_success: "メモを更新しました。"
     dryrun_is_passed: この設定でのdry-runが成功しました
+    no_diff: ファイル間の差異はありません。
 
   terms: &terms
     name: アカウント名

spec/features/fluentd/setting/histories_spec.rb

@@ -26,7 +26,8 @@ describe "histories", stub: :daemon do
   end
 
   describe 'show' do
-    let(:last_backup_file) { Fluentd::SettingArchive::BackupFile.new(daemon.agent.backup_files_in_new_order.first) }
+    let!(:last_backup_file) { Fluentd::SettingArchive::BackupFile.new(daemon.agent.backup_files_in_new_order.first) }
+    let!(:new_file) { Fluentd::SettingArchive::BackupFile.new(daemon.agent.backup_files_in_new_order[1]) }
 
     before do
       visit "/daemon/setting/histories/#{last_backup_file.file_id}"
@@ -37,11 +38,25 @@ describe "histories", stub: :daemon do
       page.should have_text(last_backup_file.content)
     end
 
-    it 'shows diff between current and target' do
-      page.should have_text("-   type http")
-      page.should have_text("+   type forward")
-      page.should have_text("-   port 8899")
-      page.should have_text("+   port 24224")
+    describe 'diff' do
+      context 'has diff' do
+        it 'shows diff between current and target' do
+          page.should have_text("-   type http")
+          page.should have_text("+   type forward")
+          page.should have_text("-   port 8899")
+          page.should have_text("+   port 24224")
+        end
+      end
+
+      context 'has no diff' do
+        before do
+          visit "/daemon/setting/histories/#{new_file.file_id}"
+        end
+
+        it 'shows no diff message' do
+          page.should have_text(I18n.t('messages.no_diff'))
+        end
+      end
     end
 
     it 'update config and redirect to setting#show' do

spec/features/fluentd/setting/running_backup_spec.rb

@@ -8,7 +8,7 @@ describe "running_backup", stub: :daemon do
     login_with exists_user
   end
 
-  context 'has running backup file' do
+  context 'has no running backup file' do
     before do
       visit '/daemon/setting/running_backup'
     end
@@ -36,10 +36,25 @@ describe "running_backup", stub: :daemon do
         expect(page).to have_text(I18n.t("terms.reuse"))
       end
 
-      it 'has diff' do
-        expect(page).to have_text("-   type http")
-        expect(page).to have_text("-   port 8899")
-        expect(page).to have_text("+   Running backup file content")
+      describe 'diff' do
+        context 'has diff' do
+          it 'shows diff between current and running' do
+            expect(page).to have_text("-   type http")
+            expect(page).to have_text("-   port 8899")
+            expect(page).to have_text("+   Running backup file content")
+          end
+        end
+
+        context 'has no diff' do
+          before do
+            daemon.agent.config_write backup_content
+            visit '/daemon/setting/running_backup'
+          end
+
+          it 'shows no diff message' do
+            page.should have_text(I18n.t('messages.no_diff'))
+          end
+        end
       end
 
       it 'update config and redirect to setting#show' do