Remove product suffixes from generated anchors

Issue: https://gitlab.com/gitlab-org/gitlab/-/issues/218764

* Update id of headers with product suffixes
* Update href of links with product suffixes

1 files changed, 38 insertions, 0 deletions

diff --git a/lib/filters/gitlab_kramdown.rb b/lib/filters/gitlab_kramdown.rb
index 5923508f..a7ba987d 100644
--- a/lib/filters/gitlab_kramdown.rb
+++ b/lib/filters/gitlab_kramdown.rb
@@ -13,6 +13,8 @@ module Nanoc::Filters
 
     PATCH
 
+    PRODUCT_SUFFIX = /-(core|starter|premium|ultimate)(-only)?/.freeze
+
     # Runs the content through [GitLab Kramdown](https://gitlab.com/brodock/gitlab_kramdown).
     # Parameters passed to this filter will be passed on to Kramdown.
     #
@@ -27,6 +29,8 @@ module Nanoc::Filters
       content = with_toc ? TOC_PATCH+raw_content : raw_content
       document = ::Kramdown::Document.new(content, params)
 
+      update_anchors_with_product_suffixes!(document.root.children)
+
       if warning_filters
         r = Regexp.union(warning_filters)
         warnings = document.warnings.reject { |warning| r =~ warning }
@@ -43,5 +47,39 @@ module Nanoc::Filters
 
       document.to_html
     end
+
+    private
+
+    def update_anchors_with_product_suffixes!(elements)
+      headers = find_type_elements(:header, elements)
+
+      headers.each do |header|
+        next unless header.attr['id'].match(PRODUCT_SUFFIX)
+
+        remove_product_suffix!(header, 'id')
+
+        link = find_type_elements(:a, header.children).first
+
+        remove_product_suffix!(link, 'href') if link
+      end
+    end
+
+    def remove_product_suffix!(element, attr)
+      element.attr[attr] = element.attr[attr].gsub(PRODUCT_SUFFIX, '')
+    end
+
+    def find_type_elements(type, elements)
+      results = []
+
+      elements.each do |e|
+        results.push(e) if type == e.type
+
+        unless e.children.empty?
+          results.concat(find_type_elements(type, e.children))
+        end
+      end
+
+      results
+    end
   end
 end