Fix saving diffs that are not valid UTF-8

Previously, we used Psych, which would:

1. Check if a string was encoded as binary, and not ASCII-compatible.
2. Add the !binary tag in that case.
3. Convert to base64.

We need to do the same thing, using a new column in place of the tag.

1 files changed, 9 insertions, 0 deletions

diff --git a/spec/models/merge_request_diff_spec.rb b/spec/models/merge_request_diff_spec.rb
index edc2f4bb9f0..0e77752bccc 100644
--- a/spec/models/merge_request_diff_spec.rb
+++ b/spec/models/merge_request_diff_spec.rb
@@ -105,6 +105,15 @@ describe MergeRequestDiff, models: true do
 
       expect(mr_diff.empty?).to be_truthy
     end
+
+    it 'saves binary diffs correctly' do
+      path = 'files/images/icn-time-tracking.pdf'
+      mr_diff = create(:merge_request, source_branch: 'add-pdf-text-binary', target_branch: 'master').merge_request_diff
+      diff_file = mr_diff.merge_request_diff_files.find_by(new_path: path)
+
+      expect(diff_file).to be_binary
+      expect(diff_file.diff).to eq(mr_diff.compare.diffs(paths: [path]).to_a.first.diff)
+    end
   end
 
   describe '#commit_shas' do