Add latest changes from gitlab-org/gitlab@master

1 files changed, 156 insertions, 0 deletions

diff --git a/spec/lib/gitlab/experimentation_spec.rb b/spec/lib/gitlab/experimentation_spec.rb
new file mode 100644
index 00000000000..4d473731f39
--- /dev/null
+++ b/spec/lib/gitlab/experimentation_spec.rb
@@ -0,0 +1,156 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Experimentation::ControllerConcern, type: :controller do
+  controller(ApplicationController) do
+    include Gitlab::Experimentation::ControllerConcern
+
+    def index
+      head :ok
+    end
+  end
+
+  describe '#set_experimentation_subject_id_cookie' do
+    before do
+      get :index
+    end
+
+    context 'cookie is present' do
+      before do
+        cookies[:experimentation_subject_id] = 'test'
+      end
+
+      it 'does not change the cookie' do
+        expect(cookies[:experimentation_subject_id]).to eq 'test'
+      end
+    end
+
+    context 'cookie is not present' do
+      it 'sets a permanent signed cookie' do
+        expect(cookies.permanent.signed[:experimentation_subject_id]).to be_present
+      end
+    end
+  end
+
+  describe '#experiment_enabled?' do
+    context 'cookie is not present' do
+      it 'calls Gitlab::Experimentation.enabled? with the name of the experiment and an experimentation_subject_index of nil' do
+        expect(Gitlab::Experimentation).to receive(:enabled?).with(:test_experiment, nil)
+        controller.experiment_enabled?(:test_experiment)
+      end
+    end
+
+    context 'cookie is present' do
+      before do
+        cookies.permanent.signed[:experimentation_subject_id] = 'abcd-1234'
+        get :index
+      end
+
+      it 'calls Gitlab::Experimentation.enabled? with the name of the experiment and an experimentation_subject_index of the modulo 100 of the hex value of the uuid' do
+        # 'abcd1234'.hex % 100 = 76
+        expect(Gitlab::Experimentation).to receive(:enabled?).with(:test_experiment, 76)
+        controller.experiment_enabled?(:test_experiment)
+      end
+    end
+  end
+end
+
+describe Gitlab::Experimentation do
+  before do
+    stub_const('Gitlab::Experimentation::EXPERIMENTS', {
+      test_experiment: {
+        feature_toggle: feature_toggle,
+        environment: environment,
+        enabled_ratio: enabled_ratio
+      }
+    })
+
+    stub_feature_flags(feature_toggle => true)
+  end
+
+  let(:feature_toggle) { :test_experiment_toggle }
+  let(:environment) { Rails.env.test? }
+  let(:enabled_ratio) { 0.1 }
+
+  describe '.enabled?' do
+    subject { described_class.enabled?(:test_experiment, experimentation_subject_index) }
+    let(:experimentation_subject_index) { 9 }
+
+    context 'feature toggle is enabled, we are on the right environment and we are selected' do
+      it { is_expected.to be_truthy }
+    end
+
+    describe 'experiment is not defined' do
+      it 'returns false' do
+        expect(described_class.enabled?(:missing_experiment, experimentation_subject_index)).to be_falsey
+      end
+    end
+
+    describe 'feature toggle' do
+      context 'feature toggle is not set' do
+        let(:feature_toggle) { nil }
+
+        it { is_expected.to be_truthy }
+      end
+
+      context 'feature toggle is not set, but a feature with the experiment key as name does exist' do
+        before do
+          stub_feature_flags(test_experiment: false)
+        end
+
+        let(:feature_toggle) { nil }
+
+        it { is_expected.to be_falsey }
+      end
+
+      context 'feature toggle is disabled' do
+        before do
+          stub_feature_flags(feature_toggle => false)
+        end
+
+        it { is_expected.to be_falsey }
+      end
+    end
+
+    describe 'environment' do
+      context 'environment is not set' do
+        let(:environment) { nil }
+
+        it { is_expected.to be_truthy }
+      end
+
+      context 'we are on the wrong environment' do
+        let(:environment) { ::Gitlab.com? }
+
+        it { is_expected.to be_falsey }
+      end
+    end
+
+    describe 'enabled ratio' do
+      context 'enabled ratio is not set' do
+        let(:enabled_ratio) { nil }
+
+        it { is_expected.to be_falsey }
+      end
+
+      context 'experimentation_subject_index is not set' do
+        let(:experimentation_subject_index) { nil }
+
+        it { is_expected.to be_falsey }
+      end
+
+      context 'experimentation_subject_index is an empty string' do
+        let(:experimentation_subject_index) { '' }
+
+        it { is_expected.to be_falsey }
+      end
+
+      context 'experimentation_subject_index outside enabled ratio' do
+        let(:experimentation_subject_index) { 11 }
+
+        it { is_expected.to be_falsey }
+      end
+    end
+  end
+end