#90

backend/app/controllers/posts_controller.rb

@@ -148,11 +148,11 @@ class PostsController < ApplicationController
     post.reload
     render json: PostRepr.base(post), status: :created
   rescue Tag::NicoTagNormalisationError
-    head :bad_request
+    render_bad_request('ニコニコ・タグは直接指定できません．', field: :tags)
   rescue ArgumentError => e
-    render json: { errors: [e.message] }, status: :unprocessable_entity
+    render_unprocessable_entity(e.message)
   rescue ActiveRecord::RecordInvalid => e
-    render json: { errors: e.record.errors.full_messages }, status: :unprocessable_entity
+    render_model_errors(e.record)
   end
 
   def viewed
@@ -175,10 +175,10 @@ class PostsController < ApplicationController
 
     force = bool?(:force)
     merge = bool?(:merge)
-    return head :bad_request if force && merge
+    return render_bad_request('force と merge は同時に指定できません．') if force && merge
 
     base_version_no = parse_base_version_no
-    return head :bad_request if !(force) && !(base_version_no)
+    return render_bad_request('base_version_no は必須です．', field: :base_version_no) if !(force) && !(base_version_no)
 
     title = params[:title].presence
     tag_names = params[:tags].to_s.split
@@ -238,11 +238,11 @@ class PostsController < ApplicationController
     json['tags'] = build_tag_tree_for(post.tags)
     render json:, status: :ok
   rescue Tag::NicoTagNormalisationError
-    head :bad_request
+    render_bad_request('ニコニコ・タグは直接指定できません．', field: :tags)
   rescue ArgumentError => e
-    render json: { errors: [e.message] }, status: :unprocessable_entity
+    render_validation_error(fields: { parent_post_ids: [e.message] })
   rescue ActiveRecord::RecordInvalid => e
-    render json: { errors: e.record.errors.full_messages }, status: :unprocessable_entity
+    render_validation_error(e.record)
   end
 
   def changes
@@ -416,7 +416,7 @@ class PostsController < ApplicationController
 
   def sync_parent_posts! post, parent_post_ids
     if parent_post_ids.include?(post.id)
-      post.errors.add(:base, '自分自身を親投稿にはできません．')
+      post.errors.add(:parent_post_ids, '自分自身を親投稿にはできません．')
       raise ActiveRecord::RecordInvalid, post
     end