Revert "Merge branch '230689-remove-feature-flag-for-reference-filter' into 'master'"

This reverts merge request !37465

changelogs/unreleased/230689-remove-feature-flag-for-reference-filter.yml

----
-title: Improve performance of Banzai reference filters
-merge_request: 37465
-author:
-type: performance

lib/banzai/filter/reference_filter.rb

@@ -25,12 +25,14 @@ module Banzai
       def initialize(doc, context = nil, result = nil)
         super
 
+        if update_nodes_enabled?
           @new_nodes = {}
           @nodes = self.result[:reference_filter_nodes]
         end
+      end
 
       def call_and_update_nodes
-        with_update_nodes { call }
+        update_nodes_enabled? ? with_update_nodes { call } : call
       end
 
       # Returns a data attribute String to attach to a reference link
@@ -163,7 +165,11 @@ module Banzai
       end
 
       def replace_text_with_html(node, index, html)
+        if update_nodes_enabled?
           replace_and_update_new_nodes(node, index, html)
+        else
+          node.replace(html)
+        end
       end
 
       def replace_and_update_new_nodes(node, index, html)
@@ -203,6 +209,10 @@ module Banzai
         end
         result[:reference_filter_nodes] = nodes
       end
+
+      def update_nodes_enabled?
+        Feature.enabled?(:update_nodes_for_banzai_reference_filter, project)
+      end
     end
   end
 end

spec/lib/banzai/filter/reference_filter_spec.rb

@@ -110,6 +110,20 @@ RSpec.describe Banzai::Filter::ReferenceFilter do
 
         expect(filter.instance_variable_get(:@new_nodes)).to eq({ index => [filter.each_node.to_a[index]] })
       end
+
+      context "with update_nodes_for_banzai_reference_filter feature flag disabled" do
+        before do
+          stub_feature_flags(update_nodes_for_banzai_reference_filter: false)
+        end
+
+        it 'does not call replace_and_update_new_nodes' do
+          expect(filter).not_to receive(:replace_and_update_new_nodes).with(filter.nodes[index], index, html)
+
+          filter.send(method_name, *args) do
+            html
+          end
+        end
+      end
     end
   end
 
@@ -184,10 +198,15 @@ RSpec.describe Banzai::Filter::ReferenceFilter do
   end
 
   describe "#call_and_update_nodes" do
+    context "with update_nodes_for_banzai_reference_filter feature flag enabled" do
       include_context 'new nodes'
       let(:document) { Nokogiri::HTML.fragment('<a href="foo">foo</a>') }
       let(:filter) { described_class.new(document, project: project) }
 
+      before do
+        stub_feature_flags(update_nodes_for_banzai_reference_filter: true)
+      end
+
       it "updates all new nodes", :aggregate_failures do
         filter.instance_variable_set('@nodes', nodes)
 
@@ -201,6 +220,30 @@ RSpec.describe Banzai::Filter::ReferenceFilter do
       end
     end
 
+    context "with update_nodes_for_banzai_reference_filter feature flag disabled" do
+      include_context 'new nodes'
+
+      before do
+        stub_feature_flags(update_nodes_for_banzai_reference_filter: false)
+      end
+
+      it "does not change nodes", :aggregate_failures do
+        document = Nokogiri::HTML.fragment('<a href="foo">foo</a>')
+        filter = described_class.new(document, project: project)
+        filter.instance_variable_set('@nodes', nodes)
+
+        expect(filter).to receive(:call) { filter.instance_variable_set('@new_nodes', new_nodes) }
+        expect(filter).not_to receive(:with_update_nodes)
+        expect(filter).not_to receive(:update_nodes!)
+
+        filter.call_and_update_nodes
+
+        expect(filter.nodes).to eq(nodes)
+        expect(filter.result[:reference_filter_nodes]).to be nil
+      end
+    end
+  end
+
   describe ".call" do
     include_context 'new nodes'
 
@@ -208,6 +251,10 @@ RSpec.describe Banzai::Filter::ReferenceFilter do
 
     let(:result) { { reference_filter_nodes: nodes } }
 
+    before do
+      stub_feature_flags(update_nodes_for_banzai_reference_filter: true)
+    end
+
     it "updates all nodes", :aggregate_failures do
       expect_next_instance_of(described_class) do |filter|
         expect(filter).to receive(:call_and_update_nodes).and_call_original
@@ -220,5 +267,26 @@ RSpec.describe Banzai::Filter::ReferenceFilter do
 
       expect(result[:reference_filter_nodes]).to eq(expected_nodes)
     end
+
+    context "with update_nodes_for_banzai_reference_filter feature flag disabled" do
+      let(:result) { {} }
+
+      before do
+        stub_feature_flags(update_nodes_for_banzai_reference_filter: false)
+      end
+
+      it "updates all nodes", :aggregate_failures do
+        expect_next_instance_of(described_class) do |filter|
+          expect(filter).to receive(:call_and_update_nodes).and_call_original
+          expect(filter).not_to receive(:with_update_nodes)
+          expect(filter).to receive(:call) { filter.instance_variable_set('@new_nodes', new_nodes) }
+          expect(filter).not_to receive(:update_nodes!)
+        end
+
+        described_class.call(document, { project: project }, result)
+
+        expect(result[:reference_filter_nodes]).to be nil
+      end
+    end
   end
 end

spec/lib/banzai/pipeline/gfm_pipeline_spec.rb

@@ -30,6 +30,34 @@ RSpec.describe Banzai::Pipeline::GfmPipeline do
         described_class.call(markdown, project: project)
       end
 
+      context "with update_nodes_for_banzai_reference_filter feature flag disabled" do
+        before do
+          stub_feature_flags(update_nodes_for_banzai_reference_filter: false)
+        end
+
+        context 'when shorthand pattern #ISSUE_ID is used' do
+          it 'links an internal issues and doesnt store nodes in result[:reference_filter_nodes]', :aggregate_failures do
+            issue = create(:issue, project: project)
+            markdown = "text #{issue.to_reference(project, full: true)}"
+            result = described_class.call(markdown, project: project)
+            link = result[:output].css('a').first
+
+            expect(link['href']).to eq(Gitlab::Routing.url_helpers.project_issue_path(project, issue))
+            expect(result[:reference_filter_nodes]).to eq nil
+          end
+        end
+
+        it 'execute :each_node for each reference_filter', :aggregate_failures do
+          issue = create(:issue, project: project)
+          markdown = "text #{issue.to_reference(project, full: true)}"
+          described_class.reference_filters do |reference_filter|
+            expect_any_instance_of(reference_filter).to receive(:each_node).once
+          end
+
+          described_class.call(markdown, project: project)
+        end
+      end
+
       context 'when shorthand pattern #ISSUE_ID is used' do
         it 'links an internal issue  if it exists' do
           issue = create(:issue, project: project)