Add create voucher action and system test

app/controllers/admin/vouchers_controller.rb

@@ -2,10 +2,35 @@
 
 module Admin
   class VouchersController < ResourceController
+    before_action :load_enterprise
 
-   def new
-     @enterprise = Enterprise.find_by permalink: params[:enterprise_id]
-     @voucher = Voucher.new
-   end
+    def new
+      @voucher = Voucher.new
+    end
+
+    def create
+      voucher_params = permitted_resource_params.merge(enterprise: @enterprise)
+      @voucher = Voucher.create(voucher_params)
+
+      if @voucher.save
+        redirect_to(
+          "#{edit_admin_enterprise_path(@enterprise)}#vouchers_panel",
+          flash: { success: flash_message_for(@voucher, :successfully_created) }
+        )
+      else
+        flash[:error] = @voucher.errors.full_messages.to_sentence
+        render :new
+      end
+    end
+
+    private
+
+    def load_enterprise
+      @enterprise = Enterprise.find_by permalink: params[:enterprise_id]
+    end
+
+    def permitted_resource_params
+      params.require(:voucher).permit(:code)
+    end
   end
 end

spec/system/admin/vouchers_spec.rb

@@ -0,0 +1,68 @@
+# frozen_string_literal: true
+
+require 'system_helper'
+
+describe '
+    As an administrator
+    I want to manage vouchers
+' do
+  include WebHelper
+  include AuthenticationHelper
+
+  let(:enterprise) { create(:supplier_enterprise, name: 'Feedme') }
+  let(:voucher_code) { 'awesomevoucher' }
+
+  it 'lists enterprise vouchers' do
+    # Given an enterprise with vouchers
+    Voucher.create!(enterprise: enterprise, code: voucher_code)
+
+    # When I go to the enterprise voucher tab
+    login_as_admin_and_visit edit_admin_enterprise_path(enterprise)
+    click_link 'Vouchers'
+
+    # Then I see a list of vouchers
+    expect(page).to have_content voucher_code
+    expect(page).to have_content "10"
+  end
+
+  it 'creates a voucher' do
+    # Given an enterprise
+    # When I go to the new voucher page
+    login_as_admin_and_visit new_admin_enterprise_voucher_path(enterprise)
+
+    # And I fill in the fields for a new voucher click save
+    fill_in 'voucher_code', with: voucher_code
+    click_button 'Save'
+
+    # Then I should get redirect to the entreprise voucher tab and see the created voucher
+    expect(page).to have_selector '.success', text: 'Voucher has been successfully created!'
+
+    # TODO: doesn't automatically show the voucher tab
+    click_link 'Vouchers'
+
+    expect(page).to have_content voucher_code
+    expect(page).to have_content "10"
+
+    voucher = Voucher.where(enterprise: enterprise, code: voucher_code).first
+
+    expect(voucher).not_to be(nil)
+  end
+
+  context 'when entering invalid data' do
+    it 'shows an error flash message' do
+      # Given an enterprise
+      # When I go to the new voucher page
+      login_as_admin_and_visit new_admin_enterprise_voucher_path(enterprise)
+
+      # And I fill in filers with invalid data click save
+      click_button 'Save'
+
+      # Then I should see an error flash message
+      expect(page).to have_selector '.error', text: "Code can't be blank"
+
+      vouchers = Voucher.where(enterprise: enterprise)
+
+      expect(vouchers).to be_empty
+    end
+  end
+end