Move variables & logic from view into helpers

This cleans up the view and adheres to the principle of “Fat Helpers,
Skinny Views” (I’m not sure that’s a real thing, but I like it).

ee/app/helpers/ee/trial_helper.rb

@@ -13,6 +13,16 @@ module EE
       ], selected)
     end
 
+    def should_ask_company_question?
+      glm_params[:glm_source] != 'about.gitlab.com'
+    end
+
+    def glm_params
+      strong_memoize(:glm_params) do
+        params.slice(:glm_source, :glm_content).to_unsafe_h
+      end
+    end
+
     def namespace_options_for_select(selected = nil)
       grouped_options = {
         'New' => [[_('Create group'), 0]],

ee/app/views/trials/select.html.haml

 - page_title _('Start a Free Gold Trial')
-- glm_params = { glm_source: params[:glm_source], glm_content: params[:glm_content] }
-- should_ask_company_question = glm_params[:glm_source] != 'about.gitlab.com'
 
 %h3.center.pt-6
   = _('Almost there')
@@ -17,7 +15,7 @@
   #group_name.form-group.hidden
     = label_tag :new_group_name, _('New Group Name'), for: :new_group_name, class: 'col-form-label'
     = text_field_tag :new_group_name, nil, class: 'form-control'
-  - if should_ask_company_question
+  - if should_ask_company_question?
     .form-group
       = label_tag :trial_entity, _('Is this GitLab trial for your company?')
       .gl-form-checkbox-group

ee/spec/helpers/ee/trial_helper_spec.rb

@@ -5,6 +5,62 @@ require 'spec_helper'
 RSpec.describe EE::TrialHelper do
   using RSpec::Parameterized::TableSyntax
 
+  describe '#should_ask_company_question?' do
+    before do
+      allow(helper).to receive(:glm_params).and_return(glm_source ? { glm_source: glm_source } : {})
+    end
+
+    subject { helper.should_ask_company_question? }
+
+    where(:glm_source, :result) do
+      'about.gitlab.com'  | false
+      'abouts.gitlab.com' | true
+      'about.gitlab.org'  | true
+      'about.gitlob.com'  | true
+      nil                 | true
+    end
+
+    with_them do
+      it { is_expected.to eq(result) }
+    end
+  end
+
+  describe '#glm_params' do
+    let(:glm_source) { nil }
+    let(:glm_content) { nil }
+    let(:params) do
+      ActionController::Parameters.new({
+        controller: 'FooBar', action: 'stuff', id: '123'
+      }.tap do |p|
+        p[:glm_source] = glm_source if glm_source
+        p[:glm_content] = glm_content if glm_content
+      end)
+    end
+
+    before do
+      allow(helper).to receive(:params).and_return(params)
+    end
+
+    subject { helper.glm_params }
+
+    it 'is memoized' do
+      expect(helper).to receive(:strong_memoize)
+
+      subject
+    end
+
+    where(:glm_source, :glm_content, :result) do
+      nil       | nil       | {}
+      'source'  | nil       | { glm_source: 'source' }
+      nil       | 'content' | { glm_content: 'content' }
+      'source'  | 'content' | { glm_source: 'source', glm_content: 'content' }
+    end
+
+    with_them do
+      it { is_expected.to eq(HashWithIndifferentAccess.new(result)) }
+    end
+  end
+
   describe '#namespace_options_for_select' do
     let_it_be(:user) { create :user }
     let_it_be(:group1) { create :group }