diff --git a/spec/models/ci/build_spec.rb b/spec/models/ci/build_spec.rb
index 36d10636ae9..1dd26750edd 100644
--- a/spec/models/ci/build_spec.rb
+++ b/spec/models/ci/build_spec.rb
@@ -19,4 +19,55 @@ describe Ci::Build, models: true do
       expect(build.trace).to eq(test_trace)
     end
   end
+
+  describe '#has_trace_file?' do
+    context 'when there is no trace' do
+      it { expect(build.has_trace_file?).to be_falsey }
+      it { expect(build.trace).to be_nil }
+    end
+
+    context 'when there is a trace' do
+      context 'when trace is stored in file' do
+        before do
+          build.trace = test_trace
+          build.save
+        end
+
+        it { expect(build.has_trace_file?).to be_truthy }
+        it { expect(build.trace).to eq(test_trace) }
+      end
+
+      context 'when trace is stored in old file' do
+        before do
+          build.trace = test_trace
+          build.save
+
+          build.project.ci_id = 999
+          build.project.save
+
+          FileUtils.mkdir_p(build.old_dir_to_trace)
+          FileUtils.mv(build.path_to_trace, build.old_path_to_trace)
+        end
+
+        it { expect(build.has_trace_file?).to be_truthy }
+        it { expect(build.trace).to eq(test_trace) }
+      end
+
+      context 'when there is stored in DB' do
+        class Ci::Build
+          def write_db_trace=(trace)
+            write_attribute :trace, trace
+          end
+        end
+
+        before do
+          build.write_db_trace = test_trace
+          build.save
+        end
+
+        it { expect(build.has_trace_file?).to be_falsey }
+        it { expect(build.trace).to eq(test_trace) }
+      end
+    end
+  end
 end