Cucumber::ArityMismatchError

I have these .feature statements:

I am logged in as an "Teacher".
I am logged in as an "Professor".
I am logged in as an "Student".
I am logged in as a "NoRole"

for which I wrote a regex

I (\w{2})?\s?(log|login|logged)\s?(\w{2}) as (an|a) "(Teacher|Professor|Student|NoRole)"\.?

I had put them in quotes so that I can run a case block on them like this:

case role_type
     when 'Student'
       on(LoginPage).login_with(FigNewton.Studnet_email,'password')
and so on ... for other roles

Now when I run this regex in step definitions with Given

Given(/^I (\w{2})?\s?(log|login|logged)\s?(\w{2}) as (an|a) "(Teacher|Professor|Student|NoRole)"\.?$/) do |user_role|
  # code
end

it gives this error:

Cucumber::ArityMismatchError: Your block takes 1 argument, but the Regexp matched 5 arguments

Query: As far as I know, arguments are those in between quotes like "Professor" so which five arguments it is talking about.

On this Cucumber::ArityMismatchError error after Transform I found that there shouldn't be any block, but my regex wont work if there are no blocks, So how to separated role type from regex arguments(blocks)

Solution

As the error message says, the step definition is expecting one argument - user_role. However, you are capturing 5 groups, which means you are passing 5 arguments:

(\w{2})
(log|login|logged)
(\w{2})
(an|a)
(Teacher|Professor|Student|NoRole)

Given that you only want the last group, (Teacher|Professor|Student|NoRole), the other 4 groups should be marked as non-capturing groups. This is done by adding a ?: after the opening parenthesis:

Given(/^I (?:\w{2})?\s?(?:log|login|logged)\s?(?:\w{2}) as (?:an|a) "(Teacher|Professor|Student|NoRole|Owner)"\.?$/)

Note that the "Owner" role was missing from the user_role group (and is added above). This step will match all 5 of the expected steps.