Stdlib::Email type

Add new type to validate emails.  The regex has been taken from the
[html5 spec][1]

[1]: https://html.spec.whatwg.org/multipage/input.html#valid-e-mail-address

Author: b4ldr

spec/type_aliases/email_spec.rb

@@ -0,0 +1,67 @@
+require 'spec_helper'
+
+# Test cases are a combination of the test cases used in MediaWiki[1] and a
+# Reference found on line[2].  Some of the test cases in the later list have
+# been dropped as the regex used in the HTML5 specification[3] (and in this type)
+# allows for wilful violation of the RFC's
+#
+# [1]https://github.com/wikimedia/mediawiki/blob/master/tests/phpunit/integration \
+#   /includes/SanitizerValidateEmailTest.php
+# [2]https://gist.github.com/cjaoude/fd9910626629b53c4d25
+# [3]https://html.spec.whatwg.org/multipage/input.html#valid-e-mail-address
+
+describe 'Stdlib::Email' do
+  describe 'valid handling' do
+    ['email@example.com',
+     'EMAIL@example.com',
+     'email@EXAMPLE.com',
+     'email@192.0.2.1',
+     '_______@example.com',
+     'firstname.lastname@example.com',
+     'firstname+lastname@example.com',
+     'firstname-lastname@example.com',
+     '1234567890@example.com',
+     'email@subdomain.example.com',
+     'email@example-one.com',
+     'email@example.name',
+     'email@example.museum',
+     'email@example.co.jp',
+     'email@example',
+     'user@example.1234',
+     'user@a'].each do |value|
+      describe value.inspect do
+        it { is_expected.to allow_value(value) }
+      end
+    end
+  end
+  describe 'invalid handling' do
+    ['plainaddress',
+     '#@%^%#$@#$@#.com',
+     '@example.com',
+     ' email@example.com',
+     'email@example.com ',
+     "email@example.com\t",
+     'user email@example.com',
+     'useremail@example com',
+     'user,email@example.com',
+     'useremail@example,com',
+     'useremail@.',
+     'useremail@.example.org',
+     'useremail@a......',
+     'useràexample.com',
+     'Joe Smith <email@example.com>',
+     'email.example.com',
+     'email@example@example.com',
+     'あいうえお@example.com',
+     'email@example.com (Joe Smith)',
+     'email@-example.com',
+     'email@example..com',
+     '”(),:;<>[\]@example.com',
+     'just”not”right@example.com',
+     'this\ is"really"not\allowed@example.com'].each do |value|
+      describe value.inspect do
+        it { is_expected.not_to allow_value(value) }
+      end
+    end
+  end
+end

types/email.pp

@@ -0,0 +1,2 @@
+# https://html.spec.whatwg.org/multipage/input.html#valid-e-mail-address
+type Stdlib::Email = Pattern[/^[a-zA-Z0-9.!#$%&'*+\/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$/]