Specifying minimum length when using FFaker::Internet.user_name

Question

I have a spec that keeps failing because FFaker::Internet.user_name generates a word that is less than 5 characters.

How do I specify a minimum length in this stmt:

username { FFaker::Internet.user_name }

Answer 1

String#ljust — Returns a copy of self of a given length, right-padded with a given other string.

username { FFaker::Internet.user_name.ljust(5,"12345") }

Answer 2

From what I see you try to use FFaker in your factory. Why overcomplicate things for your specs, when you could define sequence

sequence(:username) do |n|
   "username-#{n}"
end

But the question is valid and you may have some legitimate needs to use ffaker, and there are many ways to do it. You can just concatenate username twice, why not?

username { FFaker.username + FFaker.username }

Or keep looking for a username that length is of minimal lenght:

username do
   do
     name = FFaker.username
   while name.length < 5
   name
end

Or monkeypatch ffaker and implement it yourself https://github.com/ffaker/ffaker/blob/0578f7fd31c9b485e9c6fa15f25b3eca724790fe/lib/ffaker/internet.rb#L43 + https://github.com/ffaker/ffaker/blob/0578f7fd31c9b485e9c6fa15f25b3eca724790fe/lib/ffaker/name.rb#L75

for example

class FFaker
  def long_username(min_length = 5)
    fetch_sample(FIRST_NAMES.select {|name| name.length >= min_lenght })
  end
end

Answer 3

There're many ways you can achieve this, but if I had to do it, I'd do something like

(FFaker::Internet.user_name + '___')[0...5]
#=> "Lily_"

There are three underscores because after the quick lookup to the name list, I found the minimum length of first name is two characters so two plus three will always be at least five characters.

I'm only taking five character substring so as to not always have trailing underscore, but that's just my personal preference, you can use username plus three underscores and your test case will do fine.

Answer 4

You can't, but you could do FFaker::Name.name.join, this generates first name and middle name

Answer 5

You can also build it manually with regex using FFaker::String like so:

# 5 characters username, with first character being a letter
username { FFaker::String.from_regexp(/[a-zA-Z]\w{4}/) }

# random 5-10 characters username with first character being a letter
regex = Regexp.new("[a-zA-Z]\\w{#{Random.rand(4..9)}}")
username { FFaker::String.from_regexp(regex) }

Answer 6

Another idea is to add some random numbers to the end. This worked for me, was easy to implement, and looks fairly natural (since humans tend to do it when creating usernames in the wild).

E.g. this adds "1234" to the end of usernames:

"steve" + "1234"

and with Faker:

Faker::Internet.unique.user_name + "1234"

Note: if you want a random string (instead of "1234", try some of these approaches. However, it may not be necessary if you're already using the Faker .unique method as in the above example.