1 files changed, 55 insertions, 0 deletions
diff --git a/spec/lib/gitlab/diff/diff_refs_spec.rb b/spec/lib/gitlab/diff/diff_refs_spec.rb
index c73708d90a8..f9bfb4c469e 100644
--- a/spec/lib/gitlab/diff/diff_refs_spec.rb
+++ b/spec/lib/gitlab/diff/diff_refs_spec.rb
@@ -3,6 +3,61 @@ require 'spec_helper'
 describe Gitlab::Diff::DiffRefs do
   let(:project) { create(:project, :repository) }
 
+  describe '#==' do
+    let(:commit) { project.commit('1a0b36b3cdad1d2ee32457c102a8c0b7056fa863') }
+    subject { commit.diff_refs }
+
+    context 'when shas are missing' do
+      let(:other) { described_class.new(base_sha: subject.base_sha, start_sha: subject.start_sha, head_sha: nil) }
+
+      it 'returns false' do
+        expect(subject).not_to eq(other)
+      end
+    end
+
+    context 'when shas are equal' do
+      let(:other) { described_class.new(base_sha: subject.base_sha, start_sha: subject.start_sha, head_sha: subject.head_sha) }
+
+      it 'returns true' do
+        expect(subject).to eq(other)
+      end
+    end
+
+    context 'when shas are unequal' do
+      let(:other) { described_class.new(base_sha: subject.base_sha, start_sha: subject.start_sha, head_sha: subject.head_sha.reverse) }
+
+      it 'returns false' do
+        expect(subject).not_to eq(other)
+      end
+    end
+
+    context 'when shas are truncated' do
+      context 'when sha prefixes are too short' do
+        let(:other) { described_class.new(base_sha: subject.base_sha[0, 4], start_sha: subject.start_sha[0, 4], head_sha: subject.head_sha[0, 4]) }
+
+        it 'returns false' do
+          expect(subject).not_to eq(other)
+        end
+      end
+
+      context 'when sha prefixes are equal' do
+        let(:other) { described_class.new(base_sha: subject.base_sha[0, 10], start_sha: subject.start_sha[0, 10], head_sha: subject.head_sha[0, 10]) }
+
+        it 'returns true' do
+          expect(subject).to eq(other)
+        end
+      end
+
+      context 'when sha prefixes are unequal' do
+        let(:other) { described_class.new(base_sha: subject.base_sha[0, 10], start_sha: subject.start_sha[0, 10], head_sha: subject.head_sha[0, 10].reverse) }
+
+        it 'returns false' do
+          expect(subject).not_to eq(other)
+        end
+      end
+    end
+  end
+
   describe '#compare_in' do
     context 'with diff refs for the initial commit' do
       let(:commit) { project.commit('1a0b36b3cdad1d2ee32457c102a8c0b7056fa863') }