Add custom expectations for authentication activity metrics

lib/gitlab/auth/activity.rb

@@ -47,8 +47,14 @@ module Gitlab
         self.class.user_signed_out_counter.increment
       end
 
+      def self.each_counter
         COUNTERS.each_pair do |metric, description|
-        define_singleton_method("#{metric}_counter") do
+          yield "#{metric}_counter", metric, description
+        end
+      end
+
+      each_counter do |counter, metric, description|
+        define_singleton_method(counter) do
           strong_memoize(metric) do
             Gitlab::Metrics.counter("gitlab_auth_#{metric}_total".to_sym, description)
           end

spec/features/users/login_spec.rb

@@ -3,6 +3,10 @@ require 'spec_helper'
 describe 'Login' do
   include TermsHelper
 
+  before do
+    stub_authentication_activity_metrics
+  end
+
   it 'Successful user signin invalidates password reset token' do
     user = create(:user)
 
@@ -29,7 +33,6 @@ describe 'Login' do
       User.delete_all
 
       user = create(:admin, password_automatically_set: true)
-      expect(Gitlab::Auth::Activity).to increment(:user_authenticated_counter)
 
       visit root_path
       expect(current_path).to eq edit_user_password_path
@@ -47,6 +50,7 @@ describe 'Login' do
       click_button 'Sign in'
 
       expect(current_path).to eq root_path
+      expect(authentication_metrics).to have_incremented(:user_authenticated_counter)
     end
 
     it 'does not show flash messages when login page' do

spec/lib/gitlab/auth/activity_spec.rb

@@ -3,8 +3,8 @@ require 'spec_helper'
 describe Gitlab::Auth::Activity do
   describe 'counters' do
     it 'has all static counters defined' do
-      described_class::COUNTERS.each_key do |metric|
-        expect(described_class).to respond_to("#{metric}_counter")
+      described_class.each_counter do |counter|
+        expect(described_class).to respond_to(counter)
       end
     end
   end

spec/support/helpers/stub_configuration.rb

@@ -68,6 +68,17 @@ module StubConfiguration
     allow(Gitlab.config.repositories).to receive(:storages).and_return(Settingslogic.new(messages))
   end
 
+  def authentication_metrics
+    Gitlab::Auth::Activity
+  end
+
+  def stub_authentication_activity_metrics
+    authentication_metrics.each_counter do |counter, metric, description|
+      allow(authentication_metrics).to receive(counter)
+        .and_return(spy("#{metric} - #{description}"))
+    end
+  end
+
   private
 
   # Modifies stubbed messages to also stub possible predicate versions

spec/support/prometheus/custom_matchers.rb

-RSpec::Matchers.define :increment do |counter|
-  match do |metric|
-    expect(metric.send(counter)).to receive(:increment)
+RSpec::Matchers.define :have_incremented do |counter|
+  match do |adapter|
+    matcher = RSpec::Mocks::Matchers::HaveReceived.new(:increment)
+
+    matcher.matches?(adapter.send(counter))
   end
 end