1 files changed, 73 insertions, 0 deletions
diff --git a/spec/lib/gitlab/sherlock/line_profiler_spec.rb b/spec/lib/gitlab/sherlock/line_profiler_spec.rb
new file mode 100644
index 00000000000..8f2e1299714
--- /dev/null
+++ b/spec/lib/gitlab/sherlock/line_profiler_spec.rb
@@ -0,0 +1,73 @@
+require 'spec_helper'
+
+describe Gitlab::Sherlock::LineProfiler do
+  let(:profiler) { described_class.new }
+
+  describe '#profile' do
+    it 'runs the profiler when using MRI' do
+      allow(profiler).to receive(:mri?).and_return(true)
+      allow(profiler).to receive(:profile_mri)
+
+      profiler.profile { 'cats' }
+    end
+
+    it 'raises NotImplementedError when profiling an unsupported platform' do
+      allow(profiler).to receive(:mri?).and_return(false)
+
+      expect { profiler.profile { 'cats' } }.to raise_error(NotImplementedError)
+    end
+  end
+
+  describe '#profile_mri' do
+    it 'returns an Array containing the return value and profiling samples' do
+      allow(profiler).to receive(:lineprof).
+        and_yield.
+        and_return({ __FILE__ => [[0, 0, 0, 0]] })
+
+      retval, samples = profiler.profile_mri { 42 }
+
+      expect(retval).to eq(42)
+      expect(samples).to eq([])
+    end
+  end
+
+  describe '#aggregate_rblineprof' do
+    let(:raw_samples) do
+      { __FILE__ => [[30000, 30000, 5, 0], [15000, 15000, 4, 0]] }
+    end
+
+    it 'returns an Array of FileSample objects' do
+      samples = profiler.aggregate_rblineprof(raw_samples)
+
+      expect(samples).to be_an_instance_of(Array)
+      expect(samples[0]).to be_an_instance_of(Gitlab::Sherlock::FileSample)
+    end
+
+    describe 'the first FileSample object' do
+      let(:file_sample) do
+        profiler.aggregate_rblineprof(raw_samples)[0]
+      end
+
+      it 'uses the correct file path' do
+        expect(file_sample.file).to eq(__FILE__)
+      end
+
+      it 'contains a list of line samples' do
+        line_sample = file_sample.line_samples[0]
+
+        expect(line_sample).to be_an_instance_of(Gitlab::Sherlock::LineSample)
+
+        expect(line_sample.duration).to eq(15.0)
+        expect(line_sample.events).to eq(4)
+      end
+
+      it 'contains the total file execution time' do
+        expect(file_sample.duration).to eq(30.0)
+      end
+
+      it 'contains the total amount of file events' do
+        expect(file_sample.events).to eq(5)
+      end
+    end
+  end
+end