Add service classes for mutating AwardEmoji

Adding, destroying and toggling emoji previously lacked services and
instead were performed through methods called on Awardable models.

This led to inconsistencies where relevant todos would be marked as done
only when emoji were awarded through our controllers, but not through
the API. Todos could also be marked as done when an emoji was being
removed.

Behaviour changes

- Awarding emoji through the API will now mark a relevant Todo as done
- Toggling an emoji off (destroying it) through our controllers will no
  longer mark a relevant Todo as done

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/63372

3 files changed, 264 insertions, 0 deletions

diff --git a/spec/services/award_emojis/add_service_spec.rb b/spec/services/award_emojis/add_service_spec.rb
new file mode 100644
index 00000000000..037db39ba80
--- /dev/null
+++ b/spec/services/award_emojis/add_service_spec.rb
@@ -0,0 +1,103 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe AwardEmojis::AddService do
+  set(:user) { create(:user) }
+  set(:project) { create(:project) }
+  set(:awardable) { create(:note, project: project) }
+  let(:name) { 'thumbsup' }
+  subject(:service) { described_class.new(awardable, name, user) }
+
+  describe '#execute' do
+    context 'when user is not authorized' do
+      it 'does not add an emoji' do
+        expect { service.execute }.not_to change { AwardEmoji.count }
+      end
+
+      it 'returns an error state' do
+        result = service.execute
+
+        expect(result[:status]).to eq(:error)
+        expect(result[:http_status]).to eq(:forbidden)
+      end
+    end
+
+    context 'when user is authorized' do
+      before do
+        project.add_developer(user)
+      end
+
+      it 'creates an award emoji' do
+        expect { service.execute }.to change { AwardEmoji.count }.by(1)
+      end
+
+      it 'returns the award emoji' do
+        result = service.execute
+
+        expect(result[:award]).to be_kind_of(AwardEmoji)
+      end
+
+      it 'return a success status' do
+        result = service.execute
+
+        expect(result[:status]).to eq(:success)
+      end
+
+      it 'sets the correct properties on the award emoji' do
+        award = service.execute[:award]
+
+        expect(award.name).to eq(name)
+        expect(award.user).to eq(user)
+      end
+
+      describe 'marking Todos as done' do
+        subject { service.execute }
+
+        include_examples 'creating award emojis marks Todos as done'
+      end
+
+      context 'when the awardable cannot have emoji awarded to it' do
+        before do
+          expect(awardable).to receive(:emoji_awardable?).and_return(false)
+        end
+
+        it 'does not add an emoji' do
+          expect { service.execute }.not_to change { AwardEmoji.count }
+        end
+
+        it 'returns an error status' do
+          result = service.execute
+
+          expect(result[:status]).to eq(:error)
+          expect(result[:http_status]).to eq(:unprocessable_entity)
+        end
+      end
+
+      context 'when the awardable is invalid' do
+        before do
+          expect_next_instance_of(AwardEmoji) do |award|
+            expect(award).to receive(:valid?).and_return(false)
+            expect(award).to receive_message_chain(:errors, :full_messages).and_return(['Error 1', 'Error 2'])
+          end
+        end
+
+        it 'does not add an emoji' do
+          expect { service.execute }.not_to change { AwardEmoji.count }
+        end
+
+        it 'returns an error status' do
+          result = service.execute
+
+          expect(result[:status]).to eq(:error)
+        end
+
+        it 'returns an error message' do
+          result = service.execute
+
+          expect(result[:message]).to eq('Error 1 and Error 2')
+        end
+      end
+    end
+  end
+end
diff --git a/spec/services/award_emojis/destroy_service_spec.rb b/spec/services/award_emojis/destroy_service_spec.rb
new file mode 100644
index 00000000000..c4a7d5ec20e
--- /dev/null
+++ b/spec/services/award_emojis/destroy_service_spec.rb
@@ -0,0 +1,89 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe AwardEmojis::DestroyService do
+  set(:user) { create(:user) }
+  set(:awardable) { create(:note) }
+  set(:project) { awardable.project }
+  let(:name) { 'thumbsup' }
+  let!(:award_from_other_user) do
+    create(:award_emoji, name: name, awardable: awardable, user: create(:user))
+  end
+  subject(:service) { described_class.new(awardable, name, user) }
+
+  describe '#execute' do
+    shared_examples_for 'a service that does not authorize the user' do |error:|
+      it 'does not remove the emoji' do
+        expect { service.execute }.not_to change { AwardEmoji.count }
+      end
+
+      it 'returns an error state' do
+        result = service.execute
+
+        expect(result[:status]).to eq(:error)
+        expect(result[:http_status]).to eq(:forbidden)
+      end
+
+      it 'returns a nil award' do
+        result = service.execute
+
+        expect(result).to have_key(:award)
+        expect(result[:award]).to be_nil
+      end
+
+      it 'returns the error' do
+        result = service.execute
+
+        expect(result[:message]).to eq(error)
+        expect(result[:errors]).to eq([error])
+      end
+    end
+
+    context 'when user is not authorized' do
+      it_behaves_like 'a service that does not authorize the user',
+                      error: 'User cannot destroy emoji on the awardable'
+    end
+
+    context 'when the user is authorized' do
+      before do
+        project.add_developer(user)
+      end
+
+      context 'when user has not awarded an emoji to the awardable' do
+        let!(:award_from_user) { create(:award_emoji, name: name, user: user) }
+
+        it_behaves_like 'a service that does not authorize the user',
+                         error: 'User has not awarded emoji of type thumbsup on the awardable'
+      end
+
+      context 'when user has awarded an emoji to the awardable' do
+        let!(:award_from_user) { create(:award_emoji, name: name, awardable: awardable, user: user) }
+
+        it 'removes the emoji' do
+          expect { service.execute }.to change { AwardEmoji.count }.by(-1)
+        end
+
+        it 'returns a success status' do
+          result = service.execute
+
+          expect(result[:status]).to eq(:success)
+        end
+
+        it 'returns no errors' do
+          result = service.execute
+
+          expect(result).not_to have_key(:error)
+          expect(result).not_to have_key(:errors)
+        end
+
+        it 'returns the destroyed award' do
+          result = service.execute
+
+          expect(result[:award]).to eq(award_from_user)
+          expect(result[:award]).to be_destroyed
+        end
+      end
+    end
+  end
+end
diff --git a/spec/services/award_emojis/toggle_service_spec.rb b/spec/services/award_emojis/toggle_service_spec.rb
new file mode 100644
index 00000000000..972a1d5fc06
--- /dev/null
+++ b/spec/services/award_emojis/toggle_service_spec.rb
@@ -0,0 +1,72 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe AwardEmojis::ToggleService do
+  set(:user) { create(:user) }
+  set(:project) { create(:project, :public) }
+  set(:awardable) { create(:note, project: project) }
+  let(:name) { 'thumbsup' }
+  subject(:service) { described_class.new(awardable, name, user) }
+
+  describe '#execute' do
+    context 'when user has awarded an emoji' do
+      let!(:award_from_other_user) { create(:award_emoji, name: name, awardable: awardable, user: create(:user)) }
+      let!(:award) { create(:award_emoji, name: name, awardable: awardable, user: user) }
+
+      it 'calls AwardEmojis::DestroyService' do
+        expect(AwardEmojis::AddService).not_to receive(:new)
+
+        expect_next_instance_of(AwardEmojis::DestroyService) do |service|
+          expect(service).to receive(:execute)
+        end
+
+        service.execute
+      end
+
+      it 'destroys an AwardEmoji' do
+        expect { service.execute }.to change { AwardEmoji.count }.by(-1)
+      end
+
+      it 'returns the result of DestroyService#execute' do
+        mock_result = double(foo: true)
+
+        expect_next_instance_of(AwardEmojis::DestroyService) do |service|
+          expect(service).to receive(:execute).and_return(mock_result)
+        end
+
+        result = service.execute
+
+        expect(result).to eq(mock_result)
+      end
+    end
+
+    context 'when user has not awarded an emoji' do
+      it 'calls AwardEmojis::AddService' do
+        expect_next_instance_of(AwardEmojis::AddService) do |service|
+          expect(service).to receive(:execute)
+        end
+
+        expect(AwardEmojis::DestroyService).not_to receive(:new)
+
+        service.execute
+      end
+
+      it 'creates an AwardEmoji' do
+        expect { service.execute }.to change { AwardEmoji.count }.by(1)
+      end
+
+      it 'returns the result of AddService#execute' do
+        mock_result = double(foo: true)
+
+        expect_next_instance_of(AwardEmojis::AddService) do |service|
+          expect(service).to receive(:execute).and_return(mock_result)
+        end
+
+        result = service.execute
+
+        expect(result).to eq(mock_result)
+      end
+    end
+  end
+end