Remove wiki_front_matter FF

Remove the wiki_front_matter
Feature flag to add
the feature by default.

Changelog: added

app/models/wiki_page.rb

@@ -316,7 +316,6 @@ class WikiPage
   end
 
   def update_front_matter(attrs)
-    return unless Gitlab::WikiPages::FrontMatterParser.enabled?(container)
     return unless attrs.has_key?(:front_matter)
 
     fm_yaml = serialize_front_matter(attrs[:front_matter])
@@ -327,7 +326,7 @@ class WikiPage
 
   def parsed_content
     strong_memoize(:parsed_content) do
-      Gitlab::WikiPages::FrontMatterParser.new(raw_content, container).parse
+      Gitlab::WikiPages::FrontMatterParser.new(raw_content).parse
     end
   end
 

config/feature_flags/development/wiki_front_matter.yml

----
-name: wiki_front_matter
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/27706
-rollout_issue_url: 
-milestone: '12.10'
-type: development
-group: group::editor
-default_enabled: false

lib/gitlab/wiki_pages/front_matter_parser.rb

@@ -3,8 +3,6 @@
 module Gitlab
   module WikiPages
     class FrontMatterParser
-      FEATURE_FLAG = :wiki_front_matter
-
       # We limit the maximum length of text we are prepared to parse as YAML, to
       # avoid exploitations and attempts to consume memory and CPU. We allow for:
       #  - a title line
@@ -30,18 +28,12 @@ module Gitlab
       end
 
       # @param [String] wiki_content
-      # @param [FeatureGate] feature_gate The scope for feature availability
-      def initialize(wiki_content, feature_gate)
+      def initialize(wiki_content)
         @wiki_content = wiki_content
-        @feature_gate = feature_gate
-      end
-
-      def self.enabled?(gate = nil)
-        Feature.enabled?(FEATURE_FLAG, gate)
       end
 
       def parse
-        return empty_result unless enabled? && wiki_content.present?
+        return empty_result unless wiki_content.present?
         return empty_result(block.error) unless block.valid?
 
         Result.new(front_matter: block.data, content: strip_front_matter_block)
@@ -94,16 +86,12 @@ module Gitlab
 
       private
 
-      attr_reader :wiki_content, :feature_gate
+      attr_reader :wiki_content
 
       def empty_result(reason = nil, error = nil)
         Result.new(content: wiki_content, reason: reason, error: error)
       end
 
-      def enabled?
-        self.class.enabled?(feature_gate)
-      end
-
       def block
         @block ||= parse_front_matter_block
       end

spec/lib/gitlab/wiki_pages/front_matter_parser_spec.rb

@@ -3,11 +3,10 @@
 require 'spec_helper'
 
 RSpec.describe Gitlab::WikiPages::FrontMatterParser do
-  subject(:parser) { described_class.new(raw_content, gate) }
+  subject(:parser) { described_class.new(raw_content) }
 
   let(:content) { 'This is the content' }
   let(:end_divider) { '---' }
-  let(:gate) { stub_feature_flag_gate('Gate') }
 
   let(:with_front_matter) do
     <<~MD
@@ -62,32 +61,6 @@ RSpec.describe Gitlab::WikiPages::FrontMatterParser do
       it { is_expected.to have_attributes(reason: :no_match) }
     end
 
-    context 'the feature flag is disabled' do
-      let(:raw_content) { with_front_matter }
-
-      before do
-        stub_feature_flags(Gitlab::WikiPages::FrontMatterParser::FEATURE_FLAG => false)
-      end
-
-      it { is_expected.to have_attributes(front_matter: be_empty, content: raw_content) }
-    end
-
-    context 'the feature flag is enabled for the gated object' do
-      let(:raw_content) { with_front_matter }
-
-      before do
-        stub_feature_flags(Gitlab::WikiPages::FrontMatterParser::FEATURE_FLAG => gate)
-      end
-
-      it do
-        is_expected.to have_attributes(
-          front_matter: have_correct_front_matter,
-          content: content + "\n",
-          reason: be_nil
-        )
-      end
-    end
-
     context 'the end divider is ...' do
       let(:end_divider) { '...' }
       let(:raw_content) { with_front_matter }

spec/models/wiki_page_spec.rb

@@ -24,14 +24,6 @@ RSpec.describe WikiPage do
     container.wiki
   end
 
-  def disable_front_matter
-    stub_feature_flags(Gitlab::WikiPages::FrontMatterParser::FEATURE_FLAG => false)
-  end
-
-  def enable_front_matter_for(thing)
-    stub_feature_flags(Gitlab::WikiPages::FrontMatterParser::FEATURE_FLAG => thing)
-  end
-
   # Use for groups of tests that do not modify their `subject`.
   #
   #   include_context 'subject is persisted page', title: 'my title'
@@ -48,12 +40,6 @@ RSpec.describe WikiPage do
       it { expect(wiki_page).to have_attributes(front_matter: {}, content: content) }
     end
 
-    shared_examples 'a page with front-matter' do
-      let(:front_matter) { { title: 'Foo', slugs: %w[slug_a slug_b] } }
-
-      it { expect(wiki_page.front_matter).to eq(front_matter) }
-    end
-
     context 'the wiki page has front matter' do
       let(:content) do
         <<~MD
@@ -68,27 +54,13 @@ RSpec.describe WikiPage do
         MD
       end
 
-      it_behaves_like 'a page with front-matter'
+      it 'has front-matter' do
+        expect(wiki_page.front_matter).to eq({ title: 'Foo', slugs: %w[slug_a slug_b] })
+      end
 
       it 'strips the front matter from the content' do
         expect(wiki_page.content.strip).to eq('My actual content')
       end
-
-      context 'the feature flag is off' do
-        before do
-          disable_front_matter
-        end
-
-        it_behaves_like 'a page without front-matter'
-
-        context 'but enabled for the container' do
-          before do
-            enable_front_matter_for(container)
-          end
-
-          it_behaves_like 'a page with front-matter'
-        end
-      end
     end
 
     context 'the wiki page does not have front matter' do
@@ -471,29 +443,6 @@ RSpec.describe WikiPage do
           end
         end
 
-        context 'the front-matter feature flag is not enabled' do
-          before do
-            disable_front_matter
-          end
-
-          it 'does not update the front-matter' do
-            content = subject.content
-            subject.update(front_matter: { slugs: ['x'] })
-
-            page = wiki.find_page(subject.title)
-
-            expect([subject, page]).to all(have_attributes(front_matter: be_empty, content: content))
-          end
-
-          context 'but it is enabled for the container' do
-            before do
-              enable_front_matter_for(container)
-            end
-
-            it_behaves_like 'able to update front-matter'
-          end
-        end
-
         it 'updates the wiki-page front-matter and content together' do
           content = 'totally new content'
           subject.update(content: content, front_matter: { slugs: ['x'] })