1 files changed, 59 insertions, 0 deletions
diff --git a/spec/migrations/remove_redundant_pipeline_stages_spec.rb b/spec/migrations/remove_redundant_pipeline_stages_spec.rb
new file mode 100644
index 00000000000..8325f986594
--- /dev/null
+++ b/spec/migrations/remove_redundant_pipeline_stages_spec.rb
@@ -0,0 +1,59 @@
+require 'spec_helper'
+require Rails.root.join('db', 'post_migrate', '20180119121225_remove_redundant_pipeline_stages.rb')
+
+describe RemoveRedundantPipelineStages, :migration do
+  let(:projects) { table(:projects) }
+  let(:pipelines) { table(:ci_pipelines) }
+  let(:stages) { table(:ci_stages) }
+  let(:builds) { table(:ci_builds) }
+
+  before do
+    projects.create!(id: 123, name: 'gitlab', path: 'gitlab-ce')
+    pipelines.create!(id: 234, project_id: 123, ref: 'master', sha: 'adf43c3a')
+
+    stages.create!(id: 6, project_id: 123, pipeline_id: 234, name: 'build')
+    stages.create!(id: 10, project_id: 123, pipeline_id: 234, name: 'build')
+    stages.create!(id: 21, project_id: 123, pipeline_id: 234, name: 'build')
+    stages.create!(id: 41, project_id: 123, pipeline_id: 234, name: 'test')
+    stages.create!(id: 62, project_id: 123, pipeline_id: 234, name: 'test')
+    stages.create!(id: 102, project_id: 123, pipeline_id: 234, name: 'deploy')
+
+    builds.create!(id: 1, commit_id: 234, project_id: 123, stage_id: 10)
+    builds.create!(id: 2, commit_id: 234, project_id: 123, stage_id: 21)
+    builds.create!(id: 3, commit_id: 234, project_id: 123, stage_id: 21)
+    builds.create!(id: 4, commit_id: 234, project_id: 123, stage_id: 41)
+    builds.create!(id: 5, commit_id: 234, project_id: 123, stage_id: 62)
+    builds.create!(id: 6, commit_id: 234, project_id: 123, stage_id: 102)
+  end
+
+  it 'removes ambiguous stages and preserves builds' do
+    expect(stages.all.count).to eq 6
+    expect(builds.all.count).to eq 6
+
+    migrate!
+
+    expect(stages.all.count).to eq 1
+    expect(builds.all.count).to eq 6
+    expect(builds.all.pluck(:stage_id).compact).to eq [102]
+  end
+
+  it 'retries when incorrectly added index exception is caught' do
+    allow_any_instance_of(described_class)
+      .to receive(:remove_redundant_pipeline_stages!)
+
+    expect_any_instance_of(described_class)
+      .to receive(:remove_outdated_index!)
+      .exactly(100).times.and_call_original
+
+    expect { migrate! }
+      .to raise_error StandardError, /Failed to add an unique index/
+  end
+
+  it 'does not retry when unknown exception is being raised' do
+    allow(subject).to receive(:remove_outdated_index!)
+    expect(subject).to receive(:remove_redundant_pipeline_stages!).once
+    allow(subject).to receive(:add_unique_index!).and_raise(StandardError)
+
+    expect { subject.up(attempts: 3) }.to raise_error StandardError
+  end
+end