Introduce feature flagsuggest-diff-lines-merge

5 files changed, 33 insertions, 0 deletions

diff --git a/app/controllers/projects/application_controller.rb b/app/controllers/projects/application_controller.rb
index e0677ce3fbc..67b38582c9f 100644
--- a/app/controllers/projects/application_controller.rb
+++ b/app/controllers/projects/application_controller.rb
@@ -6,6 +6,10 @@ class Projects::ApplicationController < ApplicationController
   include ProjectUnauthorized
   include ChecksCollaboration
 
+  before_action do
+    push_frontend_feature_flag(Suggestion::FEATURE_FLAG)
+  end
+
   skip_before_action :authenticate_user!
   before_action :project
   before_action :repository
diff --git a/app/models/suggestion.rb b/app/models/suggestion.rb
index 326a9f83a65..e721c5d3639 100644
--- a/app/models/suggestion.rb
+++ b/app/models/suggestion.rb
@@ -1,11 +1,17 @@
 # frozen_string_literal: true
 
 class Suggestion < ApplicationRecord
+  FEATURE_FLAG = :diff_suggestions
+
   belongs_to :diff_note, inverse_of: :suggestions
   validates :diff_note, presence: true
 
   delegate :project, :position, :diff_file, :noteable, to: :diff_note
 
+  def self.feature_enabled?
+    Feature.enabled?(FEATURE_FLAG)
+  end
+
   def from_line
     position.new_line
   end
@@ -19,6 +25,8 @@ class Suggestion < ApplicationRecord
   alias_method :to_line_index, :from_line_index
 
   def appliable?
+    return false unless self.class.feature_enabled?
+
     !applied? &&
       diff_note.active? &&
       diff_file.new_blob &&
diff --git a/lib/banzai/filter/suggestion_filter.rb b/lib/banzai/filter/suggestion_filter.rb
index 7c6d8eef942..22cb41391ec 100644
--- a/lib/banzai/filter/suggestion_filter.rb
+++ b/lib/banzai/filter/suggestion_filter.rb
@@ -7,6 +7,8 @@ module Banzai
       TAG_CLASS = 'js-render-suggestion'.freeze
 
       def call
+        return doc unless Suggestion.feature_enabled?
+
         doc.search('pre.suggestion > code').each do |node|
           node.add_class(TAG_CLASS)
         end
diff --git a/spec/lib/banzai/filter/suggestion_filter_spec.rb b/spec/lib/banzai/filter/suggestion_filter_spec.rb
index 2b1c42f846c..2d3b1297e2c 100644
--- a/spec/lib/banzai/filter/suggestion_filter_spec.rb
+++ b/spec/lib/banzai/filter/suggestion_filter_spec.rb
@@ -13,4 +13,15 @@ describe Banzai::Filter::SuggestionFilter do
 
     expect(result[:class]).to include('js-render-suggestion')
   end
+
+  it 'includes no `js-render-suggestion` when feature disabled' do
+    stub_feature_flags(diff_suggestions: false)
+
+    input = "<pre class='code highlight js-syntax-highlight suggestion'><code>foo\n</code></pre>"
+
+    doc = filter(input)
+    result = doc.css('code').first
+
+    expect(result[:class]).to be_nil
+  end
 end
diff --git a/spec/models/suggestion_spec.rb b/spec/models/suggestion_spec.rb
index ea1135c64cf..ae2f851a936 100644
--- a/spec/models/suggestion_spec.rb
+++ b/spec/models/suggestion_spec.rb
@@ -14,6 +14,14 @@ describe Suggestion do
   end
 
   describe '#appliable?' do
+    context 'when feature is disabled' do
+      it 'returns false' do
+        stub_feature_flags(Suggestion::FEATURE_FLAG => false)
+
+        expect(suggestion).not_to be_appliable
+      end
+    end
+
     context 'when new blob does not exists' do
       it 'returns false' do
         expect_next_instance_of(DiffNote) do |diff_note|