public void With_null_existingConnection_throws()
 {
     Assert.Equal(
         "existingConnection", Assert.Throws <ArgumentNullException>(() => Database.Exists((DbConnection)null)).ParamName);
 }
 public void With_whitespace_nameOrConnectionString_throws()
 {
     Assert.Equal(
         Strings.ArgumentIsNullOrWhitespace("nameOrConnectionString"),
         Assert.Throws <ArgumentException>(() => Database.Exists(" ")).Message);
 }