Optimize system note visibility checking by hiding notes that

have been fully redacted and contain cross-project references.

The previous implementation relied on Note#cross_reference_not_visible_for?,
which essentially tries to render all the Markdown references in a system note
and only displays the note if the user can see the referring project. But this
duplicated the work that Banzai::NotesRenderer was doing already. Instead, for
each note we render, we memoize the number of visible user references and
use it later if it is available.

Improves #19273

2 files changed, 28 insertions, 4 deletions

diff --git a/spec/lib/banzai/object_renderer_spec.rb b/spec/lib/banzai/object_renderer_spec.rb
index 44256b32bdc..d99175967af 100644
--- a/spec/lib/banzai/object_renderer_spec.rb
+++ b/spec/lib/banzai/object_renderer_spec.rb
@@ -17,6 +17,7 @@ describe Banzai::ObjectRenderer do
         and_call_original
 
       expect(object).to receive(:note_html=).with('<p>hello</p>')
+      expect(object).to receive(:user_visible_reference_count=).with(0)
 
       renderer.render([object], :note)
     end
@@ -25,6 +26,7 @@ describe Banzai::ObjectRenderer do
   describe '#render_objects' do
     it 'renders an Array of objects' do
       object = double(:object, note: 'hello')
+
       renderer = described_class.new(project, user)
 
       expect(renderer).to receive(:render_attribute).with(object, :note).
@@ -38,7 +40,7 @@ describe Banzai::ObjectRenderer do
   end
 
   describe '#redact_documents' do
-    it 'redacts a set of documents and returns them as an Array of Strings' do
+    it 'redacts a set of documents and returns them as an Array of Hashes' do
       doc = Nokogiri::HTML.fragment('<p>hello</p>')
       renderer = described_class.new(project, user)
 
@@ -48,7 +50,9 @@ describe Banzai::ObjectRenderer do
 
       redacted = renderer.redact_documents([doc])
 
-      expect(redacted).to eq(['<p>hello</p>'])
+      expect(redacted.count).to eq(1)
+      expect(redacted.first[:visible_reference_count]).to eq(0)
+      expect(redacted.first[:document].to_html).to eq('<p>hello</p>')
     end
   end
 
diff --git a/spec/lib/banzai/redactor_spec.rb b/spec/lib/banzai/redactor_spec.rb
index 488f465bcda..254657a881d 100644
--- a/spec/lib/banzai/redactor_spec.rb
+++ b/spec/lib/banzai/redactor_spec.rb
@@ -15,11 +15,31 @@ describe Banzai::Redactor do
 
       expect(redactor).to receive(:nodes_visible_to_user).and_return([])
 
-      expect(redactor.redact([doc1, doc2])).to eq([doc1, doc2])
+      redacted_data = redactor.redact([doc1, doc2])
 
+      expect(redacted_data.map { |data| data[:document] }).to eq([doc1, doc2])
+      expect(redacted_data.map { |data| data[:visible_reference_count] }).to eq([0, 0])
       expect(doc1.to_html).to eq('foo')
       expect(doc2.to_html).to eq('bar')
     end
+
+    it 'does not redact an Array of documents' do
+      doc1_html = '<a class="gfm" data-reference-type="issue">foo</a>'
+      doc1 = Nokogiri::HTML.fragment(doc1_html)
+
+      doc2_html = '<a class="gfm" data-reference-type="issue">bar</a>'
+      doc2 = Nokogiri::HTML.fragment(doc2_html)
+
+      nodes = redactor.document_nodes([doc1, doc2]).map { |x| x[:nodes] }
+      expect(redactor).to receive(:nodes_visible_to_user).and_return(nodes.flatten)
+
+      redacted_data = redactor.redact([doc1, doc2])
+
+      expect(redacted_data.map { |data| data[:document] }).to eq([doc1, doc2])
+      expect(redacted_data.map { |data| data[:visible_reference_count] }).to eq([1, 1])
+      expect(doc1.to_html).to eq(doc1_html)
+      expect(doc2.to_html).to eq(doc2_html)
+    end
   end
 
   describe '#redact_nodes' do
@@ -31,7 +51,7 @@ describe Banzai::Redactor do
         with([node]).
         and_return(Set.new)
 
-      redactor.redact_nodes([node])
+      redactor.redact_document_nodes([{ document: doc, nodes: [node] }])
 
       expect(doc.to_html).to eq('foo')
     end