Undefined method `assert' error appears while running the code

Rails
1

Hi,

I am new to ruby and I am using ruby with selenium. I want to apply some
validations for login section.
Following is the code on which I am getting error.

@selenium.click “id=loginCloseButton”
@selenium.click “css=#lnkLogin > span”
@selenium.click “//button[@id=’’]”

  begin
    assert @selenium.is_text_present("* Please provide your email

address")
rescue Test::Unit::AssertionFailedError
@verification_errors << $!
end

I am getting following error while running the code:

undefined method `assert’ for #Object:0x298f9e8 (NoMethodError)

Please help me to resolve this issue or tell me any other commands for
that.

Thanks in advance.