AI: address issue #152

backend/app/models/post_implication.rb

@@ -8,7 +8,6 @@ class PostImplication < ApplicationRecord
   validates :parent_post_id, presence: true
 
   validate :parent_post_mustnt_be_itself
-  validate :parent_post_mustnt_create_cycle
 
   private
 
@@ -17,24 +16,4 @@ class PostImplication < ApplicationRecord
       errors.add :parent_post_id, '親投稿に同じ投稿を設定することはできません．'
     end
   end
-
-  def parent_post_mustnt_create_cycle
-    return if post_id.blank? || parent_post_id.blank?
-    return if errors[:parent_post_id].present?
-
-    ancestor_ids = Set.new
-    frontier_ids = [parent_post_id]
-
-    until frontier_ids.empty?
-      if frontier_ids.include?(post_id)
-        errors.add :parent_post_id, :invalid
-        return
-      end
-
-      ancestor_ids.merge(frontier_ids)
-      frontier_ids = PostImplication.where(post_id: frontier_ids)
-          .distinct.pluck(:parent_post_id)
-          .reject { ancestor_ids.include?(_1) }
-    end
-  end
 end

backend/spec/models/post_implication_spec.rb

@@ -48,47 +48,4 @@ RSpec.describe PostImplication, type: :model do
     expect(duplicate).not_to be_valid
     expect(duplicate.errors[:post_id]).to be_present
   end
-
-  it 'rejects a parent that would create a two-post cycle' do
-    described_class.create!(post: post_record, parent_post:)
-
-    implication = described_class.new(
-        post: parent_post, parent_post: post_record)
-
-    expect(implication).not_to be_valid
-    expect(implication.errors.of_kind?(:parent_post_id, :invalid)).to be true
-  end
-
-  it 'rejects a parent that would create a three-post cycle' do
-    ancestor_post = create(:post)
-    described_class.create!(post: post_record, parent_post:)
-    described_class.create!(post: parent_post, parent_post: ancestor_post)
-
-    implication = described_class.new(
-        post: ancestor_post, parent_post: post_record)
-
-    expect(implication).not_to be_valid
-    expect(implication.errors.of_kind?(:parent_post_id, :invalid)).to be true
-  end
-
-  it 'allows a parent with an ancestor when no cycle would result' do
-    ancestor_post = create(:post)
-    described_class.create!(post: parent_post, parent_post: ancestor_post)
-
-    implication = described_class.new(post: post_record, parent_post:)
-
-    expect(implication).to be_valid
-  end
-
-  it 'terminates when existing ancestors already contain a cycle' do
-    ancestor_post = create(:post)
-    described_class.create!(post: parent_post, parent_post: ancestor_post)
-    legacy_implication = described_class.new(
-        post: ancestor_post, parent_post:)
-    legacy_implication.save!(validate: false)
-
-    implication = described_class.new(post: post_record, parent_post:)
-
-    expect(implication).to be_valid
-  end
 end

frontend/src/components/PostEmbed.tsx

@@ -177,6 +177,37 @@ const PostEmbed: FC<Props> = (
 	      onError={onError}/>)
     }
 
+  case 'pixiv.net':
+    {
+      if (url.hostname !== 'pixiv.net' && url.hostname !== 'www.pixiv.net')
+	break
+
+      const artworkId =
+	  url.pathname === '/member_illust.php'
+	  ? url.searchParams.get ('illust_id')
+	  : url.pathname.match (
+	      /^\/(?:[a-z]{2}(?:-[A-Za-z]{2})?\/)?artworks\/(\d+)\/?$/)?.[1]
+
+      if (!(artworkId) || !(/^\d+$/.test (artworkId)))
+	break
+
+      if (embedAutoLoadMode === 'off')
+	return externalLink
+      if (shouldLoadEmbed === false)
+	return manualLoadControl
+
+      const embedUrl =
+	  `https://embed.pixiv.net/oembed_iframe.php?type=illust&id=${ artworkId }`
+
+      return (
+	  <iframe
+	      src={embedUrl}
+	      title={post.title || post.url}
+	      width={600}
+	      height={315}
+	      className="max-w-full"/>)
+    }
+
   case 'twitter.com':
   case 'x.com':
     {