2 files changed, 11 insertions, 1 deletions
diff --git a/actioncable/test/test_helper.rb b/actioncable/test/test_helper.rb
index f5b9ebf517..c924f1e475 100644
--- a/actioncable/test/test_helper.rb
+++ b/actioncable/test/test_helper.rb
@@ -17,7 +17,7 @@ Dir[File.expand_path("stubs/*.rb", __dir__)].each { |file| require file }
 
 # Set test adapter and logger
 ActionCable.server.config.cable = { "adapter" => "test" }
-ActionCable.server.config.logger = Logger.new(StringIO.new).tap { |l| l.level = Logger::UNKNOWN }
+ActionCable.server.config.logger = Logger.new(nil)
 
 class ActionCable::TestCase < ActiveSupport::TestCase
   include ActiveSupport::Testing::MethodCallAssertions
diff --git a/actioncable/test/test_helper_test.rb b/actioncable/test/test_helper_test.rb
index f82adb9c8f..90e3dbf01f 100644
--- a/actioncable/test/test_helper_test.rb
+++ b/actioncable/test/test_helper_test.rb
@@ -62,6 +62,16 @@ class TransmissionsTest < ActionCable::TestCase
 
     assert_match(/1 .* but 2/, error.message)
   end
+
+  def test_assert_no_broadcasts_failure
+    error = assert_raises Minitest::Assertion do
+      assert_no_broadcasts "test" do
+        ActionCable.server.broadcast "test", "hello"
+      end
+    end
+
+    assert_match(/0 .* but 1/, error.message)
+  end
 end
 
 class TransmitedDataTest < ActionCable::TestCase