1 files changed, 36 insertions, 0 deletions
diff --git a/spec/lib/gitlab/string_range_marker_spec.rb b/spec/lib/gitlab/string_range_marker_spec.rb
new file mode 100644
index 00000000000..7c77772b3f6
--- /dev/null
+++ b/spec/lib/gitlab/string_range_marker_spec.rb
@@ -0,0 +1,36 @@
+require 'spec_helper'
+
+describe Gitlab::StringRangeMarker, lib: true do
+  describe '#mark' do
+    context "when the rich text is html safe" do
+      let(:raw)  { "abc <def>" }
+      let(:rich) { %{<span class="abc">abc</span><span class="space"> </span><span class="def">&lt;def&gt;</span>}.html_safe }
+      let(:inline_diffs) { [2..5] }
+      subject do
+        described_class.new(raw, rich).mark(inline_diffs) do |text, left:, right:|
+          "LEFT#{text}RIGHT"
+        end
+      end
+
+      it 'marks the inline diffs' do
+        expect(subject).to eq(%{<span class="abc">abLEFTcRIGHT</span><span class="space">LEFT RIGHT</span><span class="def">LEFT&lt;dRIGHTef&gt;</span>})
+        expect(subject).to be_html_safe
+      end
+    end
+
+    context "when the rich text is not html safe" do
+      let(:raw)  { "abc <def>" }
+      let(:inline_diffs) { [2..5] }
+      subject do
+        described_class.new(raw).mark(inline_diffs) do |text, left:, right:|
+          "LEFT#{text}RIGHT"
+        end
+      end
+
+      it 'marks the inline diffs' do
+        expect(subject).to eq(%{abLEFTc &lt;dRIGHTef&gt;})
+        expect(subject).to be_html_safe
+      end
+    end
+  end
+end