1 files changed, 115 insertions, 0 deletions
diff --git a/spec/lib/gitlab/ci/pipeline_duration_spec.rb b/spec/lib/gitlab/ci/pipeline_duration_spec.rb
new file mode 100644
index 00000000000..b26728a843c
--- /dev/null
+++ b/spec/lib/gitlab/ci/pipeline_duration_spec.rb
@@ -0,0 +1,115 @@
+require 'spec_helper'
+
+describe Gitlab::Ci::PipelineDuration do
+  let(:calculated_duration) { calculate(data) }
+
+  shared_examples 'calculating duration' do
+    it do
+      expect(calculated_duration).to eq(duration)
+    end
+  end
+
+  context 'test sample A' do
+    let(:data) do
+      [[0, 1],
+       [1, 2],
+       [3, 4],
+       [5, 6]]
+    end
+
+    let(:duration) { 4 }
+
+    it_behaves_like 'calculating duration'
+  end
+
+  context 'test sample B' do
+    let(:data) do
+      [[0, 1],
+       [1, 2],
+       [2, 3],
+       [3, 4],
+       [0, 4]]
+    end
+
+    let(:duration) { 4 }
+
+    it_behaves_like 'calculating duration'
+  end
+
+  context 'test sample C' do
+    let(:data) do
+      [[0, 4],
+       [2, 6],
+       [5, 7],
+       [8, 9]]
+    end
+
+    let(:duration) { 8 }
+
+    it_behaves_like 'calculating duration'
+  end
+
+  context 'test sample D' do
+    let(:data) do
+      [[0, 1],
+       [2, 3],
+       [4, 5],
+       [6, 7]]
+    end
+
+    let(:duration) { 4 }
+
+    it_behaves_like 'calculating duration'
+  end
+
+  context 'test sample E' do
+    let(:data) do
+      [[0, 1],
+       [3, 9],
+       [3, 4],
+       [3, 5],
+       [3, 8],
+       [4, 5],
+       [4, 7],
+       [5, 8]]
+    end
+
+    let(:duration) { 7 }
+
+    it_behaves_like 'calculating duration'
+  end
+
+  context 'test sample F' do
+    let(:data) do
+      [[1, 3],
+       [2, 4],
+       [2, 4],
+       [2, 4],
+       [5, 8]]
+    end
+
+    let(:duration) { 6 }
+
+    it_behaves_like 'calculating duration'
+  end
+
+  context 'test sample G' do
+    let(:data) do
+      [[1, 3],
+       [2, 4],
+       [6, 7]]
+    end
+
+    let(:duration) { 4 }
+
+    it_behaves_like 'calculating duration'
+  end
+
+  def calculate(data)
+    periods = data.shuffle.map do |(first, last)|
+      Gitlab::Ci::PipelineDuration::Period.new(first, last)
+    end
+
+    Gitlab::Ci::PipelineDuration.from_periods(periods.sort_by(&:first))
+  end
+end