827 : emails validation in person

app/models/person.rb

@@ -23,6 +23,7 @@ class Person < ApplicationRecord
   accepts_nested_attributes_for :location
 
   validate :preferred_contact_method_present!
+  validates_with EmailValidator, fields: [:email, :email_2]
 
   def name_and_email
     "#{name} (#{email})"

app/validators/email_validator.rb

@@ -0,0 +1,13 @@
+class EmailValidator < ActiveModel::Validator
+  REGEX_EMAIL = /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\z/i
+  def validate(record)
+    options[:fields].each { |field| validate_email(record, field) } if options[:fields].any?
+  end
+
+  private
+
+  def validate_email(record, field)
+    value = record.send(field)
+    record.errors.add field, (options[:message] || "is not valid") if !value.nil? && !value.strip.empty? && !REGEX_EMAIL.match?(value)
+  end
+end

spec/validators/email_validator_spec.rb

@@ -0,0 +1,39 @@
+require 'rails_helper'
+
+RSpec.describe EmailValidator do
+  describe 'Email validation' do
+    let(:validator) { EmailValidator.new({fields: fields}) }
+    let(:fields) { [:email] }
+    let(:errors) { double('ActiveModel::Errors') }
+
+    context 'when only one mail is set' do
+      it 'should validate valid address' do
+        person = double('model', errors: errors, email: 'valid_email@test.org')
+        expect(errors).not_to receive(:add)
+        validator.validate(person)
+      end
+
+      it 'should find an error when the address is invalid' do
+        person = double('model', errors: errors, email: 'invalid@missingtld')
+        expect(errors).to receive(:add).with(:email, "is not valid")
+        validator.validate(person)
+      end
+    end
+
+    context 'when the two mails are set' do
+      let(:fields) { [:email, :email_2] }
+
+      it 'should find an error in email and email_2' do
+        person = double('model', errors: errors, email: 'invalid@missingtld', email_2: 'invalid_2@missingtld')
+        expect(errors).to receive(:add).twice
+        validator.validate(person)
+      end
+
+      it 'should find an error only in email' do
+        person = double('model', errors: errors, email: 'invalid@missingtld', email_2: 'valid@test.org')
+        expect(errors).to receive(:add).once
+        validator.validate(person)
+      end
+    end
+  end
+end