users: move emails to separate table.

* Move emails from users table to email_addresses table.
* Validate that addresses are formatted correctly and are unique across
  users. Existing invalid emails are grandfathered in.
* Add is_verified flag (the address has been confirmed by the user).
* Add is_deliverable flag (an undeliverable address is an address that bounces).
* Normalize addresses to prevent registering multiple accounts with the
  same email address (using tricks like Gmail's plus addressing).

test/factories/email_address.rb

@@ -0,0 +1,6 @@
+FactoryBot.define do
+  factory(:email_address) do
+    address { FFaker::Internet.email }
+    is_verified { true }
+  end
+end

test/factories/user.rb

@@ -4,7 +4,6 @@ FactoryBot.define do
       "user#{n}"
     end
     password {"password"}
-    email {FFaker::Internet.email}
     default_image_size {"large"}
     level {20}
     created_at {Time.now}

test/functional/maintenance/user/email_changes_controller_test.rb

@@ -5,7 +5,7 @@ module Maintenance
     class EmailChangesControllerTest < ActionDispatch::IntegrationTest
       context "in all cases" do
         setup do
-          @user = create(:user, :email => "bob@ogres.net")
+          @user = create(:user, email_address: build(:email_address, { address: "bob@ogres.net" }))
         end
 
         context "#new" do
@@ -20,16 +20,14 @@ module Maintenance
             should "work" do
               post_auth maintenance_user_email_change_path, @user, params: {:email_change => {:password => "password", :email => "abc@ogres.net"}}
               assert_redirected_to(edit_user_path(@user))
-              @user.reload
-              assert_equal("abc@ogres.net", @user.email)
+              assert_equal("abc@ogres.net", @user.reload.email_address.address)
             end
           end
 
           context "with the incorrect password" do
             should "not work" do
               post_auth maintenance_user_email_change_path, @user, params: {:email_change => {:password => "passwordx", :email => "abc@ogres.net"}}
-              @user.reload
-              assert_equal("bob@ogres.net", @user.email)
+              assert_equal("bob@ogres.net", @user.reload.email_address.address)
             end
           end
         end

test/functional/users_controller_test.rb

@@ -114,8 +114,28 @@ class UsersControllerTest < ActionDispatch::IntegrationTest
 
     context "create action" do
       should "create a user" do
-        assert_difference("User.count", 1) do
-          post users_path, params: {:user => {:name => "xxx", :password => "xxxxx1", :password_confirmation => "xxxxx1"}}
+        user_params = { name: "xxx", password: "xxxxx1", password_confirmation: "xxxxx1" }
+        post users_path, params: { user: user_params }
+
+        assert_redirected_to User.last
+        assert_equal("xxx", User.last.name)
+      end
+
+      should "create a user with a valid email" do
+        user_params = { name: "xxx", password: "xxxxx1", password_confirmation: "xxxxx1", email_address_attributes: { address: "test@gmail.com" } }
+        post users_path, params: { user: user_params }
+
+        assert_redirected_to User.last
+        assert_equal("xxx", User.last.name)
+        assert_equal("test@gmail.com", User.last.email_address.address)
+      end
+
+      should "not create a user with an invalid email" do
+        user_params = { name: "xxx", password: "xxxxx1", password_confirmation: "xxxxx1", email_address_attributes: { address: "test" } }
+
+        assert_no_difference("User.count") do
+          post users_path, params: { user: user_params }
+          assert_response :success
         end
       end
 

test/unit/dmail_test.rb

@@ -18,7 +18,7 @@ class DmailTest < ActiveSupport::TestCase
     context "that is spam" do
       should "be automatically reported and deleted" do
         @recipient = create(:user)
-        @spammer = create(:user, created_at: 2.weeks.ago, email: "akismet-guaranteed-spam@example.com")
+        @spammer = create(:user, created_at: 2.weeks.ago, email_address: build(:email_address, address: "akismet-guaranteed-spam@example.com"))
 
         SpamDetector.stubs(:enabled?).returns(true)
         dmail = create(:dmail, owner: @recipient, from: @spammer, to: @recipient, creator_ip_addr: "127.0.0.1")
@@ -87,14 +87,14 @@ class DmailTest < ActiveSupport::TestCase
     end
 
     should "send an email if the user wants it" do
-      user = create(:user, receive_email_notifications: true)
+      user = create(:user, receive_email_notifications: true, email_address: build(:email_address))
       assert_difference("ActionMailer::Base.deliveries.size", 1) do
         create(:dmail, to: user, owner: user, body: "test [[tagme]]")
       end
     end
 
     should "create only one message for a split response" do
-      user = FactoryBot.create(:user, :receive_email_notifications => true)
+      user = create(:user, receive_email_notifications: true, email_address: build(:email_address))
       assert_difference("ActionMailer::Base.deliveries.size", 1) do
         Dmail.create_split(from: CurrentUser.user, creator_ip_addr: "127.0.0.1", to_id: user.id, title: "foo", body: "foo")
       end

test/unit/spam_detector.rb

@@ -7,7 +7,7 @@ class SpamDetectorTest < ActiveSupport::TestCase
       SpamDetector.stubs(:enabled?).returns(true)
 
       @user = create(:gold_user, created_at: 1.month.ago)
-      @spammer = create(:user, created_at: 2.weeks.ago, email: "akismet-guaranteed-spam@example.com")
+      @spammer = create(:user, created_at: 2.weeks.ago, email_address: build(:email_address, address: "akismet-guaranteed-spam@example.com"))
     end
 
     context "for dmails" do

test/unit/user_deletion_test.rb

@@ -27,13 +27,13 @@ class UserDeletionTest < ActiveSupport::TestCase
 
   context "a valid user deletion" do
     setup do
-      @user = create(:user, email: "ted@danbooru.com")
+      @user = create(:user, email_address: build(:email_address))
       @deletion = UserDeletion.new(@user, "password")
     end
 
     should "blank out the email" do
       @deletion.delete!
-      assert_nil(@user.reload.email)
+      assert_nil(@user.reload.email_address)
     end
 
     should "rename the user" do