Use standalone diff stats RPC on every comparison view

1 files changed, 47 insertions, 0 deletions

diff --git a/spec/support/shared_examples/diff_file_collections.rb b/spec/support/shared_examples/diff_file_collections.rb
new file mode 100644
index 00000000000..55ce160add0
--- /dev/null
+++ b/spec/support/shared_examples/diff_file_collections.rb
@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+shared_examples 'diff statistics' do |test_include_stats_flag: true|
+  def stub_stats_find_by_path(path, stats_mock)
+    expect_next_instance_of(Gitlab::Git::DiffStatsCollection) do |collection|
+      allow(collection).to receive(:find_by_path).and_call_original
+      expect(collection).to receive(:find_by_path).with(path).and_return(stats_mock)
+    end
+  end
+
+  context 'when should request diff stats' do
+    it 'Repository#diff_stats is called' do
+      subject = described_class.new(diffable, collection_default_args)
+
+      expect(diffable.project.repository)
+        .to receive(:diff_stats)
+        .with(diffable.diff_refs.base_sha, diffable.diff_refs.head_sha)
+        .and_call_original
+
+      subject.diff_files
+    end
+
+    it 'Gitlab::Diff::File is initialized with diff stats' do
+      subject = described_class.new(diffable, collection_default_args)
+
+      stats_mock = double(Gitaly::DiffStats, path: '.gitignore', additions: 758, deletions: 120)
+      stub_stats_find_by_path(stub_path, stats_mock)
+
+      diff_file = subject.diff_files.find { |file| file.new_path == stub_path }
+
+      expect(diff_file.added_lines).to eq(stats_mock.additions)
+      expect(diff_file.removed_lines).to eq(stats_mock.deletions)
+    end
+  end
+
+  context 'when should not request diff stats' do
+    it 'Repository#diff_stats is not called' do
+      collection_default_args[:diff_options][:include_stats] = false
+
+      subject = described_class.new(diffable, collection_default_args)
+
+      expect(diffable.project.repository).not_to receive(:diff_stats)
+
+      subject.diff_files
+    end
+  end
+end