Avoid 500's when serializing legacy diff notes

2 files changed, 21 insertions, 10 deletions

diff --git a/spec/lib/gitlab/diff/file_collection/commit_spec.rb b/spec/lib/gitlab/diff/file_collection/commit_spec.rb
index 6d1b66deb6a..34ed22b8941 100644
--- a/spec/lib/gitlab/diff/file_collection/commit_spec.rb
+++ b/spec/lib/gitlab/diff/file_collection/commit_spec.rb
@@ -12,4 +12,8 @@ describe Gitlab::Diff::FileCollection::Commit do
     let(:diffable) { project.commit }
     let(:stub_path) { 'bar/branch-test.txt' }
   end
+
+  it_behaves_like 'unfoldable diff' do
+    let(:diffable) { project.commit }
+  end
 end
diff --git a/spec/lib/gitlab/diff/file_collection/merge_request_diff_spec.rb b/spec/lib/gitlab/diff/file_collection/merge_request_diff_spec.rb
index fbcf515281e..256166dbad3 100644
--- a/spec/lib/gitlab/diff/file_collection/merge_request_diff_spec.rb
+++ b/spec/lib/gitlab/diff/file_collection/merge_request_diff_spec.rb
@@ -2,22 +2,29 @@ require 'spec_helper'
 
 describe Gitlab::Diff::FileCollection::MergeRequestDiff do
   let(:merge_request) { create(:merge_request) }
-  let(:diff_files) { described_class.new(merge_request.merge_request_diff, diff_options: nil).diff_files }
+  let(:subject) { described_class.new(merge_request.merge_request_diff, diff_options: nil) }
+  let(:diff_files) { subject.diff_files }
 
-  it 'does not highlight binary files' do
-    allow_any_instance_of(Gitlab::Diff::File).to receive(:text?).and_return(false)
+  describe '#diff_files' do
+    it 'does not highlight binary files' do
+      allow_any_instance_of(Gitlab::Diff::File).to receive(:text?).and_return(false)
 
-    expect_any_instance_of(Gitlab::Diff::File).not_to receive(:highlighted_diff_lines)
+      expect_any_instance_of(Gitlab::Diff::File).not_to receive(:highlighted_diff_lines)
 
-    diff_files
-  end
+      diff_files
+    end
+
+    it 'does not highlight files marked as undiffable in .gitattributes' do
+      allow_any_instance_of(Gitlab::Diff::File).to receive(:diffable?).and_return(false)
 
-  it 'does not highlight files marked as undiffable in .gitattributes' do
-    allow_any_instance_of(Gitlab::Diff::File).to receive(:diffable?).and_return(false)
+      expect_any_instance_of(Gitlab::Diff::File).not_to receive(:highlighted_diff_lines)
 
-    expect_any_instance_of(Gitlab::Diff::File).not_to receive(:highlighted_diff_lines)
+      diff_files
+    end
+  end
 
-    diff_files
+  it_behaves_like 'unfoldable diff' do
+    let(:diffable) { merge_request.merge_request_diff }
   end
 
   it 'it uses a different cache key if diff line keys change' do