get code coverage to 100%!

spec/database_cleaner/strategy_spec.rb

@@ -0,0 +1,14 @@
+require "database_cleaner/strategy"
+
+RSpec.describe DatabaseCleaner::Strategy do
+  describe "default implementation" do
+    it "does not provide a default implementation for #clean" do
+      expect { described_class.new.clean }.to raise_exception(NotImplementedError)
+    end
+
+    it "rejects options" do
+      expect { described_class.new(only: %w[a b c]) }.to \
+        raise_exception(ArgumentError, "No options are available for the Strategy strategy.")
+    end
+  end
+end