1 files changed, 80 insertions, 0 deletions
diff --git a/spec/lib/gitlab/ci/reports/coverage_report_spec.rb b/spec/lib/gitlab/ci/reports/coverage_report_spec.rb
new file mode 100644
index 00000000000..53646f7dfc0
--- /dev/null
+++ b/spec/lib/gitlab/ci/reports/coverage_report_spec.rb
@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::Ci::Reports::CoverageReport do
+  let(:coverage_report) { described_class.new }
+
+  it { expect(coverage_report.files).to eq({}) }
+
+  describe '#empty?' do
+    context 'when no file has been added' do
+      it { expect(coverage_report.empty?).to be(true) }
+    end
+
+    context 'when file has been added' do
+      before do
+        coverage_report.add_file('app.rb', { 1 => 0, 2 => 1 })
+      end
+
+      it { expect(coverage_report.empty?).to be(false) }
+    end
+  end
+
+  describe '#pick' do
+    before do
+      coverage_report.add_file('app.rb', { 1 => 0, 2 => 1 })
+      coverage_report.add_file('routes.rb', { 3 => 1, 4 => 0 })
+    end
+
+    it 'returns only picked files while ignoring nonexistent ones' do
+      expect(coverage_report.pick(['routes.rb', 'nonexistent.txt'])).to eq({
+        files: { 'routes.rb' => { 3 => 1, 4 => 0 } }
+      })
+    end
+  end
+
+  describe '#add_file' do
+    context 'when providing two individual files' do
+      before do
+        coverage_report.add_file('app.rb', { 1 => 0, 2 => 1 })
+        coverage_report.add_file('routes.rb', { 3 => 1, 4 => 0 })
+      end
+
+      it 'initializes a new test suite and returns it' do
+        expect(coverage_report.files).to eq({
+          'app.rb' => { 1 => 0, 2 => 1 },
+          'routes.rb' => { 3 => 1, 4 => 0 }
+        })
+      end
+    end
+
+    context 'when providing the same files twice' do
+      context 'with different line coverage' do
+        before do
+          coverage_report.add_file('admin.rb', { 1 => 0, 2 => 1 })
+          coverage_report.add_file('admin.rb', { 3 => 1, 4 => 0 })
+        end
+
+        it 'initializes a new test suite and returns it' do
+          expect(coverage_report.files).to eq({
+            'admin.rb' => { 1 => 0, 2 => 1, 3 => 1, 4 => 0 }
+          })
+        end
+      end
+
+      context 'with identical line coverage' do
+        before do
+          coverage_report.add_file('projects.rb', { 1 => 0, 2 => 1 })
+          coverage_report.add_file('projects.rb', { 1 => 0, 2 => 1 })
+        end
+
+        it 'initializes a new test suite and returns it' do
+          expect(coverage_report.files).to eq({
+            'projects.rb' => { 1 => 0, 2 => 2 }
+          })
+        end
+      end
+    end
+  end
+end