Add failing test: strict mode should accept numbers only domains

[delphaber]

Hi :)

thanks for this gem!

I've noted that emails like john.doe@163.com are not considered valid in :strict mode. 163.com is a valid chinese email provider though.

I provided a failing test with this PR.

What do you think about this?

[karlwilbur]

Thanks for the PR! I expect to get this review in the next 24 hours.

[delphaber]

Thanks! It's just a failing PR :) I wanted to start a discussion on this, having a failing test first

[karlwilbur]

Got expected errors running tests:

Failures:

  1) EmailValidator validation when given the valid email when in `:strict` mode 'jonh.doe@163.com' should be valid
     Failure/Error: expect(StrictUser.new(:email => email)).to be_valid
       expected `#<StrictUser:0x0000563bcacc6e68 @attributes={:email=>"jonh.doe@163.com"}, @validation_context=nil, @e...0000563bcacc6e68 ...>, @messages={:email=>["is invalid"]}, @details={:email=>[{:error=>:invalid}]}>>.valid?` to be truthy, got false
     # ./spec/email_validator_spec.rb:172:in `block (6 levels) in <top (required)>'

  2) EmailValidator validation when given the valid email when in `:strict` mode 'jonh.doe@163.com' should be valid using EmailValidator.valid?
     Failure/Error: expect(described_class).to be_valid(email, :mode => :strict)
       expected `EmailValidator.valid?("jonh.doe@163.com", {:mode=>:strict})` to be truthy, got false
     # ./spec/email_validator_spec.rb:176:in `block (6 levels) in <top (required)>'

  3) EmailValidator validation when given the valid email when in `:strict` mode 'jonh.doe@163.com' should not be invalid using EmailValidator.valid?
     Failure/Error: expect(described_class).not_to be_invalid(email, :mode => :strict)
       expected `EmailValidator.invalid?("jonh.doe@163.com", {:mode=>:strict})` to be falsey, got true
     # ./spec/email_validator_spec.rb:180:in `block (6 levels) in <top (required)>'

  4) EmailValidator validation when given the valid email when in `:strict` mode 'jonh.doe@163.com' should match the regexp
     Failure/Error: expect(!!(email.strip =~ described_class.regexp(:mode => :strict))).to be(true)
     
       expected true
            got false
     # ./spec/email_validator_spec.rb:184:in `block (6 levels) in <top (required)>'

Finished in 3.33 seconds (files took 5.41 seconds to load)
4148 examples, 4 failures