Add missing group policy spec

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

spec/policies/group_policy_spec.rb

+require 'spec_helper'
+
+describe GroupPolicy, models: true do
+  let(:guest) { create(:user) }
+  let(:reporter) { create(:user) }
+  let(:developer) { create(:user) }
+  let(:master) { create(:user) }
+  let(:owner) { create(:user) }
+  let(:admin) { create(:admin) }
+  let(:group) { create(:group) }
+
+  let(:master_permissions) do
+    [
+      :create_projects,
+      :admin_milestones,
+      :admin_label
+    ]
+  end
+
+  let(:owner_permissions) do
+    [
+      :admin_group,
+      :admin_namespace,
+      :admin_group_member,
+      :change_visibility_level
+    ]
+  end
+
+  before do
+    group.add_guest(guest)
+    group.add_reporter(reporter)
+    group.add_developer(developer)
+    group.add_master(master)
+    group.add_owner(owner)
+  end
+
+  subject { described_class.abilities(current_user, group).to_set }
+
+  context 'with no user' do
+    let(:current_user) { nil }
+
+    it do
+      is_expected.to include(:read_group)
+      is_expected.not_to include(*master_permissions)
+      is_expected.not_to include(*owner_permissions)
+    end
+  end
+
+  context 'guests' do
+    let(:current_user) { guest }
+
+    it do
+      is_expected.to include(:read_group)
+      is_expected.not_to include(*master_permissions)
+      is_expected.not_to include(*owner_permissions)
+    end
+  end
+
+  context 'reporter' do
+    let(:current_user) { reporter }
+
+    it do
+      is_expected.to include(:read_group)
+      is_expected.not_to include(*master_permissions)
+      is_expected.not_to include(*owner_permissions)
+    end
+  end
+
+  context 'developer' do
+    let(:current_user) { developer }
+
+    it do
+      is_expected.to include(:read_group)
+      is_expected.not_to include(*master_permissions)
+      is_expected.not_to include(*owner_permissions)
+    end
+  end
+
+  context 'master' do
+    let(:current_user) { master }
+
+    it do
+      is_expected.to include(:read_group)
+      is_expected.to include(*master_permissions)
+      is_expected.not_to include(*owner_permissions)
+    end
+  end
+
+  context 'owner' do
+    let(:current_user) { owner }
+
+    it do
+      is_expected.to include(:read_group)
+      is_expected.to include(*master_permissions)
+      is_expected.to include(*owner_permissions)
+    end
+  end
+
+  context 'admin' do
+    let(:current_user) { admin }
+
+    it do
+      is_expected.to include(:read_group)
+      is_expected.to include(*master_permissions)
+      is_expected.to include(*owner_permissions)
+    end
+  end
+end