diff --git a/lib/capybara/selenium/driver.rb b/lib/capybara/selenium/driver.rb
index acad781c..a3219921 100644
--- a/lib/capybara/selenium/driver.rb
+++ b/lib/capybara/selenium/driver.rb
@@ -275,7 +275,7 @@ class Capybara::Selenium::Driver < Capybara::Driver::Base
     browser_name == "chrome"
   end
 
-  private
+private
 
   def browser_name
     options[:browser].to_s
diff --git a/lib/capybara/session/config.rb b/lib/capybara/session/config.rb
index 16dd31be..6f28c206 100644
--- a/lib/capybara/session/config.rb
+++ b/lib/capybara/session/config.rb
@@ -68,13 +68,13 @@ module Capybara
 
     remove_method :app_host=
     def app_host=(url)
-      raise ArgumentError, "Capybara.app_host should be set to a url (http://www.example.com). Tried to set to #{url.inspect}." unless url.nil? || (url =~ URI::DEFAULT_PARSER.make_regexp)
+      raise ArgumentError, "Capybara.app_host should be set to a url (http://www.example.com). Attempted to set #{url.inspect}." if url && url !~ URI::DEFAULT_PARSER.make_regexp
       @app_host = url
     end
 
     remove_method :default_host=
     def default_host=(url)
-      raise ArgumentError, "Capybara.default_host should be set to a url (http://www.example.com). Tried to set to #{url.inspect}." unless url.nil? || (url =~ URI::DEFAULT_PARSER.make_regexp)
+      raise ArgumentError, "Capybara.default_host should be set to a url (http://www.example.com). Attempted to set #{url.inspect}." if url && url !~ URI::DEFAULT_PARSER.make_regexp
       @default_host = url
     end