Add tests for flash message helpers

app/helpers/application_helper.rb

@@ -4,15 +4,17 @@ module ApplicationHelper
   end
 
   def flash_messages(opts = {})
-    flash.each do |msg_type, message|
-      concat(content_tag(:div, message, class: "alert #{bootstrap_class_for(msg_type)} alert-dismissible", role: 'alert') do
-               concat(content_tag(:button, class: 'close', data: { dismiss: 'alert' }) do
-                        concat content_tag(:span, '×'.html_safe, 'aria-hidden' => true)
-                        concat content_tag(:span, 'Close', class: 'sr-only')
-                      end)
-               concat message
-             end)
+    capture do
+      flash.each do |msg_type, message|
+        concat(content_tag(:div, message, class: "alert #{bootstrap_class_for(msg_type)} alert-dismissible", role: 'alert') do
+          concat(content_tag(:button, class: 'close', data: { dismiss: 'alert' }) do
+            concat content_tag(:span, '×'.html_safe, 'aria-hidden' => true)
+            concat content_tag(:span, 'Close', class: 'sr-only')
+          end)
+          concat message
+        end)
+      end
+      nil
     end
-    nil
   end
 end

test/helpers/application_helper_test.rb

@@ -0,0 +1,13 @@
+require 'test_helper'
+
+class ApplicationHelperTest < ActionView::TestCase
+  test "bootstrap classes for flash should return correct values" do
+    assert_equal "alert-danger", bootstrap_class_for(:error)
+    assert_equal "alert-success", bootstrap_class_for(:success)
+  end
+
+  test "bootstrap flash messages should work" do
+    flash[:error] = "Error"
+    assert_equal "<div class=\"alert alert-danger alert-dismissible\" role=\"alert\"><button class=\"close\" data-dismiss=\"alert\"><span aria-hidden=\"true\">&times;</span><span class=\"sr-only\">Close</span></button>Error</div>", flash_messages
+  end
+end