add test for rescue_from decryption error

Author: kathap

spec/unit/controllers/v3/application_controller_spec.rb

@@ -38,14 +38,18 @@ def not_found
       raise CloudController::Errors::NotFound.new_from_details('NotFound')
     end
 
-    def db_connection_error
-      raise Sequel::DatabaseConnectionError.new
+    def decryption_error
+      raise OpenSSL::Cipher::CipherError.new
     end
 
     def db_disconnect_error
       raise Sequel::DatabaseDisconnectError.new
     end
 
+    def db_connection_error
+      raise Sequel::DatabaseConnectionError.new
+    end
+
     def warnings_is_nil
       add_warning_headers(nil)
       render status: :ok, json: {}
@@ -320,6 +324,23 @@ def warnings_incorrect_type
     end
   end
 
+  describe '#handle_decryption_error' do
+    let!(:user) { set_current_user(VCAP::CloudController::User.make) }
+
+    before do
+      allow_any_instance_of(ErrorPresenter).to receive(:raise_500?).and_return(false)
+      routes.draw do
+        get 'decryption_error' => 'anonymous#decryption_error'
+      end
+    end
+
+    it 'rescues from OpenSSL::Cipher::CipherError and renders an error presenter1' do
+      get :decryption_error
+      expect(response).to have_http_status(:internal_server_error)
+      expect(response).to have_error_message(/Failed to decrypt credentials/)
+    end
+  end
+
   describe '#add_warning_headers' do
     let!(:user) { set_current_user(VCAP::CloudController::User.make) }