1 files changed, 121 insertions, 0 deletions
diff --git a/spec/lib/gitlab/ci/trace/checksum_spec.rb b/spec/lib/gitlab/ci/trace/checksum_spec.rb
new file mode 100644
index 00000000000..794794c3f69
--- /dev/null
+++ b/spec/lib/gitlab/ci/trace/checksum_spec.rb
@@ -0,0 +1,121 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::Ci::Trace::Checksum do
+  let(:build) { create(:ci_build, :running) }
+
+  subject { described_class.new(build) }
+
+  context 'when build pending state exists' do
+    before do
+      create(:ci_build_pending_state, build: build, trace_checksum: 'crc32:d4777540')
+    end
+
+    context 'when matching persisted trace chunks exist' do
+      before do
+        create_chunk(index: 0, data: 'a' * 128.kilobytes)
+        create_chunk(index: 1, data: 'b' * 128.kilobytes)
+        create_chunk(index: 2, data: 'ccccccccccccccccc')
+      end
+
+      it 'calculates combined trace chunks CRC32 correctly' do
+        expect(subject.chunks_crc32).to eq 3564598592
+        expect(subject).to be_valid
+      end
+    end
+
+    context 'when trace chunks were persisted in a wrong order' do
+      before do
+        create_chunk(index: 0, data: 'b' * 128.kilobytes)
+        create_chunk(index: 1, data: 'a' * 128.kilobytes)
+        create_chunk(index: 2, data: 'ccccccccccccccccc')
+      end
+
+      it 'makes trace checksum invalid' do
+        expect(subject).not_to be_valid
+      end
+    end
+
+    context 'when one of the trace chunks is missing' do
+      before do
+        create_chunk(index: 0, data: 'a' * 128.kilobytes)
+        create_chunk(index: 2, data: 'ccccccccccccccccc')
+      end
+
+      it 'makes trace checksum invalid' do
+        expect(subject).not_to be_valid
+      end
+    end
+
+    context 'when checksums of persisted trace chunks do not match' do
+      before do
+        create_chunk(index: 0, data: 'a' * 128.kilobytes)
+        create_chunk(index: 1, data: 'X' * 128.kilobytes)
+        create_chunk(index: 2, data: 'ccccccccccccccccc')
+      end
+
+      it 'makes trace checksum invalid' do
+        expect(subject).not_to be_valid
+      end
+    end
+
+    context 'when persisted trace chunks are missing' do
+      it 'makes trace checksum invalid' do
+        expect(subject.state_crc32).to eq 3564598592
+        expect(subject).not_to be_valid
+      end
+    end
+  end
+
+  context 'when build pending state is missing' do
+    describe '#state_crc32' do
+      it 'returns nil' do
+        expect(subject.state_crc32).to be_nil
+      end
+    end
+
+    describe '#valid?' do
+      it { is_expected.not_to be_valid }
+    end
+  end
+
+  describe '#trace_chunks' do
+    before do
+      create_chunk(index: 0, data: 'abcdefg')
+    end
+
+    it 'does not load raw_data from a database store' do
+      subject.trace_chunks.first.then do |chunk|
+        expect(chunk).to be_database
+        expect { chunk.raw_data }
+          .to raise_error ActiveModel::MissingAttributeError
+      end
+    end
+  end
+
+  describe '#last_chunk' do
+    context 'when there are no chunks' do
+      it 'returns nil' do
+        expect(subject.last_chunk).to be_nil
+      end
+    end
+
+    context 'when there are multiple chunks' do
+      before do
+        create_chunk(index: 1, data: '1234')
+        create_chunk(index: 0, data: 'abcd')
+      end
+
+      it 'returns chunk with the highest index' do
+        expect(subject.last_chunk.chunk_index).to eq 1
+      end
+    end
+  end
+
+  def create_chunk(index:, data:)
+    create(:ci_build_trace_chunk, :persisted, build: build,
+                                              chunk_index: index,
+                                              initial_data: data)
+  end
+end