1 files changed, 223 insertions, 0 deletions
diff --git a/spec/services/auto_merge/merge_when_pipeline_succeeds_service_spec.rb b/spec/services/auto_merge/merge_when_pipeline_succeeds_service_spec.rb
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+++ b/spec/services/auto_merge/merge_when_pipeline_succeeds_service_spec.rb
@@ -0,0 +1,223 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe AutoMerge::MergeWhenPipelineSucceedsService do
+  let(:user) { create(:user) }
+  let(:project) { create(:project, :repository) }
+
+  let(:mr_merge_if_green_enabled) do
+    create(:merge_request, merge_when_pipeline_succeeds: true, merge_user: user,
+                           source_branch: "master", target_branch: 'feature',
+                           source_project: project, target_project: project, state: "opened")
+  end
+
+  let(:pipeline) do
+    create(:ci_pipeline_with_one_job, ref: mr_merge_if_green_enabled.source_branch,
+                                      project: project)
+  end
+
+  let(:service) do
+    described_class.new(project, user, commit_message: 'Awesome message')
+  end
+
+  describe "#available_for?" do
+    subject { service.available_for?(mr_merge_if_green_enabled) }
+
+    let(:pipeline_status) { :running }
+
+    before do
+      create(:ci_pipeline, pipeline_status, ref: mr_merge_if_green_enabled.source_branch,
+                                            sha: mr_merge_if_green_enabled.diff_head_sha,
+                                            project: mr_merge_if_green_enabled.source_project)
+      mr_merge_if_green_enabled.update_head_pipeline
+    end
+
+    it { is_expected.to be_truthy }
+
+    context 'when the head piipeline succeeded' do
+      let(:pipeline_status) { :success }
+
+      it { is_expected.to be_falsy }
+    end
+  end
+
+  describe "#execute" do
+    let(:merge_request) do
+      create(:merge_request, target_project: project, source_project: project,
+                             source_branch: "feature", target_branch: 'master')
+    end
+
+    context 'first time enabling' do
+      before do
+        allow(merge_request)
+          .to receive_messages(head_pipeline: pipeline, actual_head_pipeline: pipeline)
+
+        service.execute(merge_request)
+      end
+
+      it 'sets the params, merge_user, and flag' do
+        expect(merge_request).to be_valid
+        expect(merge_request.merge_when_pipeline_succeeds).to be_truthy
+        expect(merge_request.merge_params).to include commit_message: 'Awesome message'
+        expect(merge_request.merge_user).to be user
+      end
+
+      it 'creates a system note' do
+        note = merge_request.notes.last
+        expect(note.note).to match %r{enabled an automatic merge when the pipeline for (\w+/\w+@)?\h{8}}
+      end
+    end
+
+    context 'already approved' do
+      let(:service) { described_class.new(project, user, new_key: true) }
+      let(:build)   { create(:ci_build, ref: mr_merge_if_green_enabled.source_branch) }
+
+      before do
+        allow(mr_merge_if_green_enabled)
+          .to receive_messages(head_pipeline: pipeline, actual_head_pipeline: pipeline)
+
+        allow(mr_merge_if_green_enabled).to receive(:mergeable?)
+          .and_return(true)
+
+        allow(pipeline).to receive(:success?).and_return(true)
+      end
+
+      it 'updates the merge params' do
+        expect(SystemNoteService).not_to receive(:merge_when_pipeline_succeeds)
+
+        service.execute(mr_merge_if_green_enabled)
+        expect(mr_merge_if_green_enabled.merge_params).to have_key(:new_key)
+      end
+    end
+  end
+
+  describe "#process" do
+    let(:merge_request_ref) { mr_merge_if_green_enabled.source_branch }
+    let(:merge_request_head) do
+      project.commit(mr_merge_if_green_enabled.source_branch).id
+    end
+
+    context 'when triggered by pipeline with valid ref and sha' do
+      let(:triggering_pipeline) do
+        create(:ci_pipeline, project: project, ref: merge_request_ref,
+                             sha: merge_request_head, status: 'success',
+                             head_pipeline_of: mr_merge_if_green_enabled)
+      end
+
+      it "merges all merge requests with merge when the pipeline succeeds enabled" do
+        allow(mr_merge_if_green_enabled)
+          .to receive_messages(head_pipeline: triggering_pipeline, actual_head_pipeline: triggering_pipeline)
+
+        expect(MergeWorker).to receive(:perform_async)
+        service.process(mr_merge_if_green_enabled)
+      end
+    end
+
+    context 'when triggered by an old pipeline' do
+      let(:old_pipeline) do
+        create(:ci_pipeline, project: project, ref: merge_request_ref,
+                             sha: '1234abcdef', status: 'success')
+      end
+
+      it 'does not merge request' do
+        expect(MergeWorker).not_to receive(:perform_async)
+        service.process(mr_merge_if_green_enabled)
+      end
+    end
+
+    context 'when triggered by pipeline from a different branch' do
+      let(:unrelated_pipeline) do
+        create(:ci_pipeline, project: project, ref: 'feature',
+                             sha: merge_request_head, status: 'success')
+      end
+
+      it 'does not merge request' do
+        expect(MergeWorker).not_to receive(:perform_async)
+        service.process(mr_merge_if_green_enabled)
+      end
+    end
+
+    context 'when pipeline is merge request pipeline' do
+      let(:pipeline) do
+        create(:ci_pipeline, :success,
+          source: :merge_request_event,
+          ref: mr_merge_if_green_enabled.merge_ref_path,
+          merge_request: mr_merge_if_green_enabled,
+          merge_requests_as_head_pipeline: [mr_merge_if_green_enabled])
+      end
+
+      it 'merges the associated merge request' do
+        allow(mr_merge_if_green_enabled)
+          .to receive_messages(head_pipeline: pipeline, actual_head_pipeline: pipeline)
+
+        expect(MergeWorker).to receive(:perform_async)
+        service.process(mr_merge_if_green_enabled)
+      end
+    end
+  end
+
+  describe "#cancel" do
+    before do
+      service.cancel(mr_merge_if_green_enabled)
+    end
+
+    it "resets all the pipeline succeeds params" do
+      expect(mr_merge_if_green_enabled.merge_when_pipeline_succeeds).to be_falsey
+      expect(mr_merge_if_green_enabled.merge_params).to eq({})
+      expect(mr_merge_if_green_enabled.merge_user).to be nil
+    end
+
+    it 'Posts a system note' do
+      note = mr_merge_if_green_enabled.notes.last
+      expect(note.note).to include 'canceled the automatic merge'
+    end
+  end
+
+  describe 'pipeline integration' do
+    context 'when there are multiple stages in the pipeline' do
+      let(:ref) { mr_merge_if_green_enabled.source_branch }
+      let(:sha) { project.commit(ref).id }
+
+      let(:pipeline) do
+        create(:ci_empty_pipeline, ref: ref, sha: sha, project: project)
+      end
+
+      let!(:build) do
+        create(:ci_build, :created, pipeline: pipeline, ref: ref,
+                                    name: 'build', stage: 'build')
+      end
+
+      let!(:test) do
+        create(:ci_build, :created, pipeline: pipeline, ref: ref,
+                                    name: 'test', stage: 'test')
+      end
+
+      before do
+        # This behavior of MergeRequest: we instantiate a new object
+        #
+        allow_any_instance_of(MergeRequest)
+          .to receive(:head_pipeline)
+          .and_wrap_original do
+            Ci::Pipeline.find(pipeline.id)
+          end
+      end
+
+      it "doesn't merge if any of stages failed" do
+        expect(MergeWorker).not_to receive(:perform_async)
+
+        build.success
+        test.reload
+        test.drop
+      end
+
+      it 'merges when all stages succeeded' do
+        expect(MergeWorker).to receive(:perform_async)
+
+        build.success
+        test.reload
+        test.success
+      end
+    end
+  end
+end