From e8db68b16198071f3eb69a0a72840845a48f7aad Mon Sep 17 00:00:00 2001
From: ArtOfCode- <hello@artofcode.co.uk>
Date: Sun, 20 Oct 2024 19:45:26 +0100
Subject: [PATCH 1/3] Silently substitute synonyms for tags

---
 app/models/post.rb |  6 +++++-
 app/models/tag.rb  | 11 +++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/app/models/post.rb b/app/models/post.rb
index de81fb53e..256b7ec85 100644
--- a/app/models/post.rb
+++ b/app/models/post.rb
@@ -203,10 +203,14 @@ def reaction_list
   # Updates the tags association from the tags_cache.
   def update_tag_associations
     tags_cache.each do |tag_name|
-      tag = Tag.find_or_create_by name: tag_name, tag_set: category.tag_set
+      tag, name = Tag.find_or_create_synonymized name: tag_name, tag_set: category.tag_set
       unless tags.include? tag
         tags << tag
       end
+      unless tags_cache.include? name
+        tags_cache.delete tag_name
+        tags_cache << name
+      end
     end
     tags.each do |tag|
       unless tags_cache.include? tag.name
diff --git a/app/models/tag.rb b/app/models/tag.rb
index 3fc1dff71..a9434fbf4 100644
--- a/app/models/tag.rb
+++ b/app/models/tag.rb
@@ -38,6 +38,17 @@ def self.search(term)
       .distinct
   end
 
+  def self.find_or_create_synonymized(name:, tag_set:)
+    existing = Tag.find_by(name: name, tag_set: tag_set)
+    if !existing.nil?
+      [existing, name]
+    else
+      synonyms = TagSynonym.joins(:tag).where(name: name, tags: { tag_set: tag_set })
+      synonymized_name = synonyms.exists? ? synonyms.first.tag.name : name
+      [Tag.find_or_create_by(name: synonymized_name, tag_set: tag_set), synonymized_name]
+    end
+  end
+
   def all_children
     query = File.read(Rails.root.join('db/scripts/tag_children.sql'))
     query = query.gsub('$ParentId', id.to_s)

From 49a4653b01b5fbf91a6ccea56214cf2202d2a6c8 Mon Sep 17 00:00:00 2001
From: ArtOfCode- <hello@artofcode.co.uk>
Date: Sun, 20 Oct 2024 19:49:06 +0100
Subject: [PATCH 2/3] Rubocop

---
 app/models/tag.rb | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/app/models/tag.rb b/app/models/tag.rb
index a9434fbf4..b3e4f4ae3 100644
--- a/app/models/tag.rb
+++ b/app/models/tag.rb
@@ -40,12 +40,12 @@ def self.search(term)
 
   def self.find_or_create_synonymized(name:, tag_set:)
     existing = Tag.find_by(name: name, tag_set: tag_set)
-    if !existing.nil?
-      [existing, name]
-    else
+    if existing.nil?
       synonyms = TagSynonym.joins(:tag).where(name: name, tags: { tag_set: tag_set })
       synonymized_name = synonyms.exists? ? synonyms.first.tag.name : name
       [Tag.find_or_create_by(name: synonymized_name, tag_set: tag_set), synonymized_name]
+    else
+      [existing, name]
     end
   end
 

From d906e77dc461bcc038bb60d639b6159fdb8e5ae4 Mon Sep 17 00:00:00 2001
From: ArtOfCode- <hello@artofcode.co.uk>
Date: Sun, 20 Oct 2024 20:12:53 +0100
Subject: [PATCH 3/3] Comments

---
 app/models/post.rb | 16 +++++++++++-----
 app/models/tag.rb  | 19 +++++++++++++++++++
 2 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/app/models/post.rb b/app/models/post.rb
index 256b7ec85..882f1f399 100644
--- a/app/models/post.rb
+++ b/app/models/post.rb
@@ -200,16 +200,20 @@ def reaction_list
 
   private
 
-  # Updates the tags association from the tags_cache.
+  ##
+  # Before-validation callback. Update the tags association from the tags_cache.
   def update_tag_associations
     tags_cache.each do |tag_name|
-      tag, name = Tag.find_or_create_synonymized name: tag_name, tag_set: category.tag_set
+      tag, name_used = Tag.find_or_create_synonymized name: tag_name, tag_set: category.tag_set
       unless tags.include? tag
         tags << tag
       end
-      unless tags_cache.include? name
+
+      # If the tags_cache doesn't include name_used then tag_name was a synonym - remove the synonym from tags_cache
+      # and add the primary for it instead.
+      unless tags_cache.include? name_used
         tags_cache.delete tag_name
-        tags_cache << name
+        tags_cache << name_used
       end
     end
     tags.each do |tag|
@@ -219,10 +223,12 @@ def update_tag_associations
     end
   end
 
+  ##
+  # Helper method for #check_attribution_notice validator. Produces a text-only attribution notice either based on
+  # values given or the current state of the post for use in post histories.
   # @param source [String, Nil] where the post originally came from
   # @param name [String, Nil] the name of the license
   # @param url [String, Nil] the url of the license
-  #
   # @return [String] an attribution notice corresponding to this post
   def attribution_text(source = nil, name = nil, url = nil)
     "Source: #{source || att_source}\nLicense name: #{name || att_license_name}\n" \
diff --git a/app/models/tag.rb b/app/models/tag.rb
index b3e4f4ae3..873a0ea95 100644
--- a/app/models/tag.rb
+++ b/app/models/tag.rb
@@ -38,6 +38,25 @@ def self.search(term)
       .distinct
   end
 
+  ##
+  # Find or create a tag within a given tag set, considering synonyms. If a synonym is given as +name+ then the primary
+  # tag for it is returned instead.
+  # @param name [String] A tag name to find or create.
+  # @param tag_set [TagSet] The tag set within which to search for or create the tag.
+  # @return [Array(Tag, String)] The found or created tag, and the final name used. If a synonymized name was given as
+  #   +name+ then this will be the primary tag name.
+  #
+  # @example +name+ does not yet exist: a new Tag is created
+  #   Tag.find_or_create_synonymized name: 'new-tag', tag_set: ...
+  #   # => [Tag, 'new-tag']
+  #
+  # @example +name+ already exists: the existing Tag is returned
+  #   Tag.find_or_create_synonymized name: 'existing-tag', tag_set: ...
+  #   # => [Tag, 'existing-tag']
+  #
+  # @example +name+ is a synonym of 'other-tag': the Tag for 'other-tag' is returned
+  #   Tag.find_or_create_synonymized name: 'synonym', tag_set: ...
+  #   # => [Tag, 'other-tag']
   def self.find_or_create_synonymized(name:, tag_set:)
     existing = Tag.find_by(name: name, tag_set: tag_set)
     if existing.nil?