Merge branch 'request-store-wrap' into 'master'

Add RequestCache to cache via RequestStore

See merge request !12920

5 files changed, 146 insertions, 9 deletions

diff --git a/spec/factories/commits.rb b/spec/factories/commits.rb
index 36b9645438a..89e260cf65b 100644
--- a/spec/factories/commits.rb
+++ b/spec/factories/commits.rb
@@ -4,14 +4,19 @@ FactoryGirl.define do
   factory :commit do
     git_commit RepoHelpers.sample_commit
     project factory: :empty_project
-    author { build(:author) }
 
     initialize_with do
       new(git_commit, project)
     end
 
+    after(:build) do |commit|
+      allow(commit).to receive(:author).and_return build(:author)
+    end
+
     trait :without_author do
-      author nil
+      after(:build) do |commit|
+        allow(commit).to receive(:author).and_return nil
+      end
     end
   end
 end
diff --git a/spec/features/participants_autocomplete_spec.rb b/spec/features/participants_autocomplete_spec.rb
index 382d83ca051..81b0a2f541b 100644
--- a/spec/features/participants_autocomplete_spec.rb
+++ b/spec/features/participants_autocomplete_spec.rb
@@ -54,7 +54,8 @@ feature 'Member autocomplete', :js do
     let(:note) { create(:note_on_commit, project: project, commit_id: project.commit.id) }
 
     before do
-      allow_any_instance_of(Commit).to receive(:author).and_return(author)
+      allow(User).to receive(:find_by_any_email)
+        .with(noteable.author_email.downcase).and_return(author)
 
       visit project_commit_path(project, noteable)
     end
diff --git a/spec/lib/gitlab/cache/request_cache_spec.rb b/spec/lib/gitlab/cache/request_cache_spec.rb
new file mode 100644
index 00000000000..5b82c216a13
--- /dev/null
+++ b/spec/lib/gitlab/cache/request_cache_spec.rb
@@ -0,0 +1,133 @@
+require 'spec_helper'
+
+describe Gitlab::Cache::RequestCache do
+  let(:klass) do
+    Class.new do
+      extend Gitlab::Cache::RequestCache
+
+      attr_accessor :id, :name, :result, :extra
+
+      def self.name
+        'ExpensiveAlgorithm'
+      end
+
+      def initialize(id, name, result, extra = nil)
+        self.id = id
+        self.name = name
+        self.result = result
+        self.extra = nil
+      end
+
+      request_cache def compute(arg)
+        result << arg
+      end
+
+      request_cache def repute(arg)
+        result << arg
+      end
+
+      def dispute(arg)
+        result << arg
+      end
+      request_cache(:dispute) { extra }
+    end
+  end
+
+  let(:algorithm) { klass.new('id', 'name', []) }
+
+  shared_examples 'cache for the same instance' do
+    it 'does not compute twice for the same argument' do
+      algorithm.compute(true)
+      result = algorithm.compute(true)
+
+      expect(result).to eq([true])
+    end
+
+    it 'computes twice for the different argument' do
+      algorithm.compute(true)
+      result = algorithm.compute(false)
+
+      expect(result).to eq([true, false])
+    end
+
+    it 'computes twice for the different class name' do
+      algorithm.compute(true)
+      allow(klass).to receive(:name).and_return('CheapAlgo')
+      result = algorithm.compute(true)
+
+      expect(result).to eq([true, true])
+    end
+
+    it 'computes twice for the different method' do
+      algorithm.compute(true)
+      result = algorithm.repute(true)
+
+      expect(result).to eq([true, true])
+    end
+
+    context 'when request_cache_key is provided' do
+      before do
+        klass.request_cache_key do
+          [id, name]
+        end
+      end
+
+      it 'computes twice for the different keys, id' do
+        algorithm.compute(true)
+        algorithm.id = 'ad'
+        result = algorithm.compute(true)
+
+        expect(result).to eq([true, true])
+      end
+
+      it 'computes twice for the different keys, name' do
+        algorithm.compute(true)
+        algorithm.name = 'same'
+        result = algorithm.compute(true)
+
+        expect(result).to eq([true, true])
+      end
+
+      it 'uses extra method cache key if provided' do
+        algorithm.dispute(true) # miss
+        algorithm.extra = true
+        algorithm.dispute(true) # miss
+        result = algorithm.dispute(true) # hit
+
+        expect(result).to eq([true, true])
+      end
+    end
+  end
+
+  context 'when RequestStore is active', :request_store do
+    it_behaves_like 'cache for the same instance'
+
+    it 'computes once for different instances when keys are the same' do
+      algorithm.compute(true)
+      result = klass.new('id', 'name', algorithm.result).compute(true)
+
+      expect(result).to eq([true])
+    end
+
+    it 'computes twice if RequestStore starts over' do
+      algorithm.compute(true)
+      RequestStore.end!
+      RequestStore.clear!
+      RequestStore.begin!
+      result = algorithm.compute(true)
+
+      expect(result).to eq([true, true])
+    end
+  end
+
+  context 'when RequestStore is inactive' do
+    it_behaves_like 'cache for the same instance'
+
+    it 'computes twice for different instances even if keys are the same' do
+      algorithm.compute(true)
+      result = klass.new('id', 'name', algorithm.result).compute(true)
+
+      expect(result).to eq([true, true])
+    end
+  end
+end
diff --git a/spec/models/commit_spec.rb b/spec/models/commit_spec.rb
index 6056d78da4e..528b211c9d6 100644
--- a/spec/models/commit_spec.rb
+++ b/spec/models/commit_spec.rb
@@ -19,17 +19,15 @@ describe Commit, models: true do
       expect(commit.author).to eq(user)
     end
 
-    it 'caches the author' do
-      allow(RequestStore).to receive(:active?).and_return(true)
+    it 'caches the author', :request_store do
       user = create(:user, email: commit.author_email)
-      expect_any_instance_of(Commit).to receive(:find_author_by_any_email).and_call_original
+      expect(User).to receive(:find_by_any_email).and_call_original
 
       expect(commit.author).to eq(user)
-      key = "commit_author:#{commit.author_email}"
+      key = "Commit:author:#{commit.author_email.downcase}"
       expect(RequestStore.store[key]).to eq(user)
 
       expect(commit.author).to eq(user)
-      RequestStore.store.clear
     end
   end
 
diff --git a/spec/services/notification_service_spec.rb b/spec/services/notification_service_spec.rb
index f1e00c1163b..4fc5eb0a527 100644
--- a/spec/services/notification_service_spec.rb
+++ b/spec/services/notification_service_spec.rb
@@ -383,7 +383,7 @@ describe NotificationService, services: true do
       before do
         build_team(note.project)
         reset_delivered_emails!
-        allow_any_instance_of(Commit).to receive(:author).and_return(@u_committer)
+        allow(note.noteable).to receive(:author).and_return(@u_committer)
         update_custom_notification(:new_note, @u_guest_custom, resource: project)
         update_custom_notification(:new_note, @u_custom_global)
       end