Fix older migrations on Ruby 3 (#16174)

lib/paperclip/schema_extensions.rb

@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+# Monkey-patch various Paperclip methods for Ruby 3.0 compatibility
+
+module Paperclip
+  module Schema
+    module StatementsExtensions
+      def add_attachment(table_name, *attachment_names)
+        raise ArgumentError, 'Please specify attachment name in your add_attachment call in your migration.' if attachment_names.empty?
+
+        options = attachment_names.extract_options!
+
+        attachment_names.each do |attachment_name|
+          COLUMNS.each_pair do |column_name, column_type|
+            column_options = options.merge(options[column_name.to_sym] || {})
+            add_column(table_name, "#{attachment_name}_#{column_name}", column_type, **column_options)
+          end
+        end
+      end
+    end
+
+    module TableDefinitionExtensions
+      def attachment(*attachment_names)
+        options = attachment_names.extract_options!
+        attachment_names.each do |attachment_name|
+          COLUMNS.each_pair do |column_name, column_type|
+            column_options = options.merge(options[column_name.to_sym] || {})
+            column("#{attachment_name}_#{column_name}", column_type, **column_options)
+          end
+        end
+      end
+    end
+  end
+end
+
+Paperclip::Schema::Statements.prepend(Paperclip::Schema::StatementsExtensions)
+Paperclip::Schema::TableDefinition.prepend(Paperclip::Schema::TableDefinitionExtensions)