[Admin] Fix unable to edit users with duplicate emails

Also fixes a mistake in showing the email edit box

app/controllers/admin/users_controller.rb

@@ -29,8 +29,8 @@ module Admin
     def update
       @user = User.find(params[:id])
       @user.validate_email_format = true
-      @user.skip_email_blank_check = true
-      @user.update!(user_params(@user))
+      @user.is_admin_edit = true
+      @user.update!(user_params(CurrentUser.user))
       if @user.saved_change_to_profile_about || @user.saved_change_to_profile_artinfo
         ModAction.log(:user_text_change, { user_id: @user.id })
       end

app/models/user.rb

@@ -64,7 +64,7 @@ class User < ApplicationRecord
   include Danbooru::HasBitFlags
   has_bit_flags BOOLEAN_ATTRIBUTES, :field => "bit_prefs"
 
-  attr_accessor :password, :old_password, :validate_email_format, :skip_email_blank_check
+  attr_accessor :password, :old_password, :validate_email_format, :is_admin_edit
 
   after_initialize :initialize_attributes, if: :new_record?
 
@@ -396,8 +396,8 @@ class User < ApplicationRecord
     end
 
     def enable_email_verification?
-      # Allow admins to edit users with blank emails
-      return false if email.blank? && !email_changed? && skip_email_blank_check
+      # Allow admins to edit users with blank/duplicate emails
+      return false if is_admin_edit && !email_changed?
       Danbooru.config.enable_email_verification? && validate_email_format
     end
 

app/views/admin/users/edit.html.erb

@@ -5,7 +5,7 @@
     <%= custom_form_for(@user, url: admin_user_path(@user), method: :put) do |f| %>
       <%= f.input :id, as: :hidden %>
       <%= f.input :name, input_html: { size: 50 } %>
-      <% if @user.is_bd_staff? %>
+      <% if CurrentUser.is_bd_staff? %>
         <%= f.input :email, input_html: { size: 50 } %>
         <div class="input">
           <label class="block" for="user_verified">Email Verified</label>

test/functional/admin/users_controller_test.rb

@@ -4,7 +4,7 @@ class Admin::UsersControllerTest < ActionDispatch::IntegrationTest
   context "Admin::UsersController" do
     setup do
       @user = create(:user)
-      @admin = create(:admin_user)
+      @admin = create(:admin_user, is_bd_staff: true)
     end
 
     context "#edit" do
@@ -36,10 +36,10 @@ class Admin::UsersControllerTest < ActionDispatch::IntegrationTest
         end
 
         should "succeed" do
-          put_auth admin_user_path(@user), @admin, params: { user: { level: "20", email: "" } }
+          put_auth admin_user_path(@user), @admin, params: { user: { level: "30", email: "" } }
           assert_redirected_to(user_path(@user))
           @user.reload
-          assert_equal(20, @user.level)
+          assert_equal(30, @user.level)
         end
 
         should "prevent invalid emails" do
@@ -48,6 +48,26 @@ class Admin::UsersControllerTest < ActionDispatch::IntegrationTest
           assert_equal("", @user.email)
         end
       end
+
+      context "on a user with duplicate email" do
+        setup do
+          @user1 = create(:user, email: "test@e621.net")
+          @user2 = create(:user, email: "test@e621.net")
+          Danbooru.config.stubs(:enable_email_verification?).returns(true)
+        end
+
+        should "allow editing if the email is not changed" do
+          put_auth admin_user_path(@user1), @admin, params: { user: { level: "30" } }
+          @user1.reload
+          assert_equal(30, @user1.level)
+        end
+
+        should "allow changing the email" do
+          put_auth admin_user_path(@user1), @admin, params: { user: { level: "20", email: "abc@e621.net" } }
+          @user1.reload
+          assert_equal("abc@e621.net", @user1.email)
+        end
+      end
     end
   end
 end