3 files changed, 117 insertions, 0 deletions
diff --git a/spec/lib/gitlab/word_diff/segments/chunk_spec.rb b/spec/lib/gitlab/word_diff/segments/chunk_spec.rb
new file mode 100644
index 00000000000..797cc42a03c
--- /dev/null
+++ b/spec/lib/gitlab/word_diff/segments/chunk_spec.rb
@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::WordDiff::Segments::Chunk do
+  subject(:chunk) { described_class.new(line) }
+
+  let(:line) { ' Hello' }
+
+  describe '#removed?' do
+    subject { chunk.removed? }
+
+    it { is_expected.to be_falsey }
+
+    context 'when line starts with "-"' do
+      let(:line) { '-Removed' }
+
+      it { is_expected.to be_truthy }
+    end
+  end
+
+  describe '#added?' do
+    subject { chunk.added? }
+
+    it { is_expected.to be_falsey }
+
+    context 'when line starts with "+"' do
+      let(:line) { '+Added' }
+
+      it { is_expected.to be_truthy }
+    end
+  end
+
+  describe '#to_s' do
+    subject { chunk.to_s }
+
+    it 'removes lead string modifier' do
+      is_expected.to eq('Hello')
+    end
+
+    context 'when chunk is empty' do
+      let(:line) { '' }
+
+      it { is_expected.to eq('') }
+    end
+  end
+
+  describe '#length' do
+    subject { chunk.length }
+
+    it { is_expected.to eq('Hello'.length) }
+  end
+end
diff --git a/spec/lib/gitlab/word_diff/segments/diff_hunk_spec.rb b/spec/lib/gitlab/word_diff/segments/diff_hunk_spec.rb
new file mode 100644
index 00000000000..5250e6d73c2
--- /dev/null
+++ b/spec/lib/gitlab/word_diff/segments/diff_hunk_spec.rb
@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::WordDiff::Segments::DiffHunk do
+  subject(:diff_hunk) { described_class.new(line) }
+
+  let(:line) { '@@ -3,14 +4,13 @@' }
+
+  describe '#pos_old' do
+    subject { diff_hunk.pos_old }
+
+    it { is_expected.to eq 3 }
+
+    context 'when diff hunk is broken' do
+      let(:line) { '@@ ??? @@' }
+
+      it { is_expected.to eq 0 }
+    end
+  end
+
+  describe '#pos_new' do
+    subject { diff_hunk.pos_new }
+
+    it { is_expected.to eq 4 }
+
+    context 'when diff hunk is broken' do
+      let(:line) { '@@ ??? @@' }
+
+      it { is_expected.to eq 0 }
+    end
+  end
+
+  describe '#first_line?' do
+    subject { diff_hunk.first_line? }
+
+    it { is_expected.to be_falsey }
+
+    context 'when diff hunk located on the first line' do
+      let(:line) { '@@ -1,14 +1,13 @@' }
+
+      it { is_expected.to be_truthy }
+    end
+  end
+
+  describe '#to_s' do
+    subject { diff_hunk.to_s }
+
+    it { is_expected.to eq(line) }
+  end
+end
diff --git a/spec/lib/gitlab/word_diff/segments/newline_spec.rb b/spec/lib/gitlab/word_diff/segments/newline_spec.rb
new file mode 100644
index 00000000000..ed5054844f1
--- /dev/null
+++ b/spec/lib/gitlab/word_diff/segments/newline_spec.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::WordDiff::Segments::Newline do
+  subject(:newline) { described_class.new }
+
+  describe '#to_s' do
+    subject { newline.to_s }
+
+    it { is_expected.to eq '' }
+  end
+end