1 files changed, 80 insertions, 5 deletions

diff --git a/spec/models/commit_spec.rb b/spec/models/commit_spec.rb
index 4e6b037a720..090f91168ad 100644
--- a/spec/models/commit_spec.rb
+++ b/spec/models/commit_spec.rb
@@ -52,22 +52,98 @@ describe Commit do
     end
   end
 
-  describe '#author' do
+  describe '#author', :request_store do
     it 'looks up the author in a case-insensitive way' do
       user = create(:user, email: commit.author_email.upcase)
       expect(commit.author).to eq(user)
     end
 
-    it 'caches the author', :request_store do
+    it 'caches the author' do
       user = create(:user, email: commit.author_email)
-      expect(User).to receive(:find_by_any_email).and_call_original
 
       expect(commit.author).to eq(user)
+
       key = "Commit:author:#{commit.author_email.downcase}"
-      expect(RequestStore.store[key]).to eq(user)
 
+      expect(RequestStore.store[key]).to eq(user)
       expect(commit.author).to eq(user)
     end
+
+    context 'using eager loading' do
+      let!(:alice) { create(:user, email: 'alice@example.com') }
+      let!(:bob) { create(:user, email: 'hunter2@example.com') }
+
+      let(:alice_commit) do
+        described_class.new(RepoHelpers.sample_commit, project).tap do |c|
+          c.author_email = 'alice@example.com'
+        end
+      end
+
+      let(:bob_commit) do
+        # The commit for Bob uses one of his alternative Emails, instead of the
+        # primary one.
+        described_class.new(RepoHelpers.sample_commit, project).tap do |c|
+          c.author_email = 'bob@example.com'
+        end
+      end
+
+      let(:eve_commit) do
+        described_class.new(RepoHelpers.sample_commit, project).tap do |c|
+          c.author_email = 'eve@example.com'
+        end
+      end
+
+      let!(:commits) { [alice_commit, bob_commit, eve_commit] }
+
+      before do
+        create(:email, user: bob, email: 'bob@example.com')
+      end
+
+      it 'executes only two SQL queries' do
+        recorder = ActiveRecord::QueryRecorder.new do
+          # Running this first ensures we don't run one query for every
+          # commit.
+          commits.each(&:lazy_author)
+
+          # This forces the execution of the SQL queries necessary to load the
+          # data.
+          commits.each { |c| c.author.try(:id) }
+        end
+
+        expect(recorder.count).to eq(2)
+      end
+
+      it "preloads the authors for Commits matching a user's primary Email" do
+        commits.each(&:lazy_author)
+
+        expect(alice_commit.author).to eq(alice)
+      end
+
+      it "preloads the authors for Commits using a User's alternative Email" do
+        commits.each(&:lazy_author)
+
+        expect(bob_commit.author).to eq(bob)
+      end
+
+      it 'sets the author to Nil if an author could not be found for a Commit' do
+        commits.each(&:lazy_author)
+
+        expect(eve_commit.author).to be_nil
+      end
+
+      it 'does not execute SQL queries once the authors are preloaded' do
+        commits.each(&:lazy_author)
+        commits.each { |c| c.author.try(:id) }
+
+        recorder = ActiveRecord::QueryRecorder.new do
+          alice_commit.author
+          bob_commit.author
+          eve_commit.author
+        end
+
+        expect(recorder.count).to be_zero
+      end
+    end
   end
 
   describe '#to_reference' do
@@ -182,7 +258,6 @@ eos
     it { is_expected.to respond_to(:date) }
     it { is_expected.to respond_to(:diffs) }
     it { is_expected.to respond_to(:id) }
-    it { is_expected.to respond_to(:to_patch) }
   end
 
   describe '#closes_issues' do