1 files changed, 40 insertions, 0 deletions
diff --git a/spec/models/diff_viewer/image_spec.rb b/spec/models/diff_viewer/image_spec.rb
new file mode 100644
index 00000000000..e959a7d5eb2
--- /dev/null
+++ b/spec/models/diff_viewer/image_spec.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe DiffViewer::Image do
+  describe '.can_render?' do
+    let(:diff_file) { double(Gitlab::Diff::File) }
+    let(:blob) { double(Gitlab::Git::Blob, binary_in_repo?: true, extension: 'png') }
+
+    subject { described_class.can_render?(diff_file, verify_binary: false) }
+
+    it 'returns false if both old and new blob are absent' do
+      allow(diff_file).to receive(:old_blob) { nil }
+      allow(diff_file).to receive(:new_blob) { nil }
+
+      is_expected.to be_falsy
+    end
+
+    it 'returns true if the old blob is present' do
+      allow(diff_file).to receive(:old_blob) { blob }
+      allow(diff_file).to receive(:new_blob) { nil }
+
+      is_expected.to be_truthy
+    end
+
+    it 'returns true if the new blob is present' do
+      allow(diff_file).to receive(:old_blob) { nil }
+      allow(diff_file).to receive(:new_blob) { blob }
+
+      is_expected.to be_truthy
+    end
+
+    it 'returns true if both old and new blobs are present' do
+      allow(diff_file).to receive(:old_blob) { blob }
+      allow(diff_file).to receive(:new_blob) { blob }
+
+      is_expected.to be_truthy
+    end
+  end
+end