Test failing when trying to run Rspec with Factory Girl - ruby-on-rails

Question

While trying to incorporate Factory Girl in my project I'm running into an error I just can't seem to solve. I wrote a test that would check if my user's first name was empty:
# spec/models/user_spec.rb
require 'rails_helper'
RSpec.describe User, :type => :model do
it 'is invalid without a first name' do
user = FactoryGirl.build(:user, first_name: nil)
expect(user).to have(1).errors_on(:first_name)
end
end
Unfortnately when I try to run this test I get this error:
1) User is invalid without a first name
Failure/Error: expect(user).to have(1).errors_on(:first_name)
expected 1 errors on :first_name, got 2
# ./spec/models/user_spec.rb:7:in `block (2 levels) in '
Here's what my factories.rb file looks like:
# spec/factories.rb
FactoryGirl.define do
factory :user do
first_name "John"
last_name "Doe"
sequence(:email) {|n| "johndoe#{n}#example.com"}
password "secret"
end
end
If it helps at all here's how my gemfile is setup:
group :development, :test do
gem 'rspec-rails'
gem 'rspec-collection_matchers'
gem 'factory_girl_rails'
end
Update
After checking my User model I believe that the second error was me mistakenly setting the presence validation twice in my model:
validates :first_name, :last_name, :email, :password, presence: true
validates :first_name, :last_name, presence: true, format: {with: /\A([^\d\W]|[-])*\Z/, message: 'cannot have any numbers or special characters'}
What I wonder now is a way for rspec to somehow point out the errors I'm dealing with instead of vaguely telling me:
expected 1 errors on :first_name, got 2

Answer 1

It seems that your user actually have 2 errors on the first_name field
To debug it you can just print the errors
RSpec.describe User, :type => :model do
it 'is invalid without a first name' do
user = FactoryGirl.build(:user, first_name: nil)
puts user.errors.messages[:first_name]
expect(user).to have(1).errors_on(:first_name)
end
end