emails: move EmailValidator into Danbooru::EmailAddress.

test/unit/danbooru_email_address_test.rb

@@ -0,0 +1,27 @@
+require 'test_helper'
+
+class DanbooruEmailAddressTest < ActiveSupport::TestCase
+  def assert_undeliverable(expected, address)
+    assert_equal(false, Danbooru::EmailAddress.new("webmaster@danbooru.donmai.us").undeliverable?(allow_smtp: true))
+  end
+
+  context "Danbooru::EmailAddress" do
+    context "#undeliverable?" do
+      should "return good addresses as deliverable" do
+        assert_undeliverable(false, "webmaster@danbooru.donmai.us")
+        assert_undeliverable(false, "noizave+spam@gmail.com")
+      end
+
+      should "return nonexistent domains as undeliverable" do
+        assert_undeliverable(true, "nobody@does.not.exist.donmai.us")
+      end
+
+      # XXX these tests are known to fail if your network blocks port 25.
+      should_eventually "return nonexistent addresses as undeliverable" do
+        assert_undeliverable(true, "does.not.exist.13yoigo34iy@gmail.com")
+        assert_undeliverable(true, "does.not.exist.13yoigo34iy@outlook.com")
+        assert_undeliverable(true, "does.not.exist.13yoigo34iy@hotmail.com")
+      end
+    end
+  end
+end