#431

backend/app/models/tag_group.rb

@@ -1,5 +1,6 @@
 class TagGroup < ApplicationRecord
   before_create { SharedResourceIdAllocator.assign!(self) }
+  before_destroy :delete_current_structure!
 
   belongs_to :created_by_user, class_name: 'User', optional: true
   belongs_to :updated_by_user, class_name: 'User', optional: true
@@ -15,4 +16,12 @@ class TagGroup < ApplicationRecord
 
   validates :name, presence: true, uniqueness: true, length: { maximum: 255 }
   validates :version_no, numericality: { only_integer: true, greater_than: 0 }
+
+  private
+
+  def delete_current_structure!
+    placements.reorder(position: :desc).each(&:delete)
+    tag_group_tags.delete_all
+    tag_group_groups.delete_all
+  end
 end

backend/app/services/post_create_plan.rb

@@ -95,14 +95,10 @@ class PostCreatePlan
   def build_default_tag_specs locale, direct_tag_specs
     default_tag_specs = []
     if direct_tag_specs.length < 10 && direct_tag_specs.none? { _1[:name] == TAGME_TAG_NAME }
-      default_tag_specs << {
-          name: TAGME_TAG_NAME,
-          category: :meta }
+      default_tag_specs << { name: TAGME_TAG_NAME, category: :meta }
     end
     if direct_tag_specs.none? { deerjikist_tag_spec?(locale, _1) }
-      default_tag_specs << {
-          name: NO_DEERJIKIST_TAG_NAME,
-          category: :meta }
+      default_tag_specs << { name: NO_DEERJIKIST_TAG_NAME, category: :meta }
     end
 
     default_tag_specs
@@ -117,9 +113,9 @@ class PostCreatePlan
   end
 
   def validate_new_tag_spec! locale, spec
-    tag_name = TagName.new(name: spec[:name], language_code: locale.language_code,
-                           script_code: locale.script_code, primary_flg: true)
     tag = Tag.new(category: spec[:category])
+    tag_name = TagName.new(tag:, name: spec[:name], language_code: locale.language_code,
+                           script_code: locale.script_code, primary_flg: true)
     return if tag_name.valid? && tag.valid?
 
     post = Post.new
@@ -140,10 +136,10 @@ class PostCreatePlan
     end
     expanded_parent_specs =
         Tag.expand_parent_tags(existing_snapshot_tags)
-           .reject(&:deprecated?)
-           .map { |tag|
-             { name: tag.name(locale.language_code),
-               category: tag.category.to_sym }
+        .reject(&:deprecated?)
+        .map { |tag|
+          { name: tag.name(locale.language_code),
+            category: tag.category.to_sym }
         }
     merge_tag_specs(snapshot_tag_specs + expanded_parent_specs)
   end
@@ -164,9 +160,10 @@ class PostCreatePlan
   def existing_tags_by_name locale
     @existing_tags_by_name ||= begin
       names = tag_names.map { canonical_tag_name_without_sections(locale, _1) }.uniq
-      TagName.where(language_code: locale.language_code, primary_flg: true, name: names)
-             .includes(:tag)
-             .each_with_object({ }) { |tag_name, tags| tags[tag_name.name] = tag_name.tag }
+      TagName
+          .where(language_code: locale.language_code, primary_flg: true, name: names)
+          .includes(:tag)
+          .each_with_object({ }) { |tag_name, tags| tags[tag_name.name] = tag_name.tag }
     end
   end
 

backend/app/services/shared_resource_id_allocator.rb

@@ -50,23 +50,20 @@ class SharedResourceIdAllocator
       raise
     end
 
+    # 明示-tic な Id. 指定は許可する．
+    return if record.id.present?
+
     next_id = record.class.uncached do
-      historical_max = HISTORY_IDS.fetch(space, []).map do |table, column|
+      historical_max = HISTORY_IDS.fetch(space, []).map { |table, column|
         quoted_table = connection.quote_table_name(table)
         quoted_column = connection.quote_column_name(column)
-        connection.select_value(
-            "SELECT MAX(#{ quoted_column }) FROM #{ quoted_table }").to_i
-      end.max.to_i
+        connection.select_value("SELECT MAX(#{ quoted_column }) FROM #{ quoted_table }").to_i
+      }.max.to_i
+
       [next_ids(connection, tables).max, historical_max + 1].max
     end
-    if record.id.present?
-      if record.id < next_id
-        raise ActiveRecord::RecordNotUnique, 'Shared ID is below the reserved position'
-      end
-    else
-      record.id = next_id
-    end
-    # The INSERT advances InnoDB's persistent counter, including explicit IDs.
+
+    record.id = next_id
   end
 
   def self.next_ids connection, tables

backend/app/services/tag_group_markdown_renderer.rb

@@ -19,15 +19,20 @@ class TagGroupMarkdownRenderer
       blocks << clean_text(@group['description'])
     end
 
-    sections = placements.select { _1.key?('section_name') }
-    if sections.any? && sections.size != placements.size
-      raise UnsupportedStructure,
-          '最上位の見出し Section と Placement の混在は Markdown にできません．'
-    end
+    first_section = placements.index { _1.key?('section_name') }
 
-    if placements.all? { _1.key?('section_name') }
-      blocks.concat(placements.map { render_heading(_1, 2) })
-    else
+    if first_section
+      if placements.drop(first_section).any? { !_1.key?('section_name') }
+        raise UnsupportedStructure,
+            '見出し Section の後に最上位 Placement は配置できません．'
+      end
+
+      if first_section.positive?
+        blocks << render_list(placements.take(first_section), 0)
+      end
+
+      blocks.concat(placements.drop(first_section).map { render_heading(_1, 2) })
+    elsif placements.any?
       blocks << render_list(placements, 0)
     end
 
@@ -74,7 +79,7 @@ class TagGroupMarkdownRenderer
       first_section = section_indexes.first
       if children[first_section..].any? { !_1.key?('section_name') }
         raise UnsupportedStructure,
-            '見出し Section と兄弟 Placement の交互配置は Markdown にできません．'
+              '見出し Section と兄弟 Placement の交互配置は Markdown にできません．'
       end
       list_nodes = children[0...first_section]
       blocks << render_list(list_nodes, 0) if list_nodes.any?