Fix spoiler_text not having "not null" constraint

db/migrate/20170125145934_add_spoiler_text_to_statuses.rb

@@ -1,5 +1,5 @@
 class AddSpoilerTextToStatuses < ActiveRecord::Migration[5.0]
   def change
-    add_column :statuses, :spoiler_text, :text, default: ""
+    add_column :statuses, :spoiler_text, :text, default: "", null: false
   end
 end

db/schema.rb

@@ -196,7 +196,7 @@ ActiveRecord::Schema.define(version: 20170125145934) do
     t.integer  "visibility",             default: 0,     null: false
     t.integer  "in_reply_to_account_id"
     t.integer  "application_id"
-    t.text     "spoiler_text",           default: ""
+    t.text     "spoiler_text",           default: "",    null: false
     t.index ["account_id"], name: "index_statuses_on_account_id", using: :btree
     t.index ["in_reply_to_id"], name: "index_statuses_on_in_reply_to_id", using: :btree
     t.index ["reblog_of_id"], name: "index_statuses_on_reblog_of_id", using: :btree