Add email validation

app/controllers/users/sessions_controller.rb

@@ -3,6 +3,8 @@ class Users::SessionsController < Devise::SessionsController
     self.resource = resource_class.new
     if params.dig("user", "email").empty?
       resource.errors.add :email, "Please enter email address"
+    elsif !email_valid?(params.dig("user", "email"))
+      resource.errors.add :email, "Email addess is not valid"
     end
     if params.dig("user", "password").empty?
       resource.errors.add :password, "Please enter password"
@@ -13,4 +15,10 @@ class Users::SessionsController < Devise::SessionsController
       super
     end
   end
+
+private
+
+  def email_valid?(email)
+    email =~ URI::MailTo::EMAIL_REGEXP
+  end
 end

spec/features/user_spec.rb

@@ -98,6 +98,15 @@ RSpec.describe "User Features" do
       expect(page).to have_selector("#user-email-field-error")
       expect(page).to have_selector("#user-password-field-error")
     end
+
+    it "show specific field error messages if an invalid email address is entered" do
+      visit("/case_logs")
+      fill_in("user[email]", with: "thisisn'tanemail")
+      click_button("Sign in")
+      expect(page).to have_selector("#error-summary-title")
+      expect(page).to have_selector("#user-email-field-error")
+      expect(page).to have_content(/Email addess is not valid/)
+    end
   end
 
   context "Your Account " do