Add RemoveColumnEnhancements for better reversability

lib/code0/zero_track/database/migration.rb

@@ -9,6 +9,7 @@ class V1_0 < ::ActiveRecord::Migration[7.1]
           include Database::MigrationHelpers::AddColumnEnhancements
           include Database::MigrationHelpers::ConstraintHelpers
           include Database::MigrationHelpers::IndexHelpers
+          include Database::MigrationHelpers::RemoveColumnEnhancements
           include Database::MigrationHelpers::TableEnhancements
         end
         # rubocop:enable Naming/ClassAndModuleCamelCase

lib/code0/zero_track/database/migration_helpers/remove_column_enhancements.rb

@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+module Code0
+  module ZeroTrack
+    module Database
+      module MigrationHelpers
+        module RemoveColumnEnhancements
+          def remove_column(table_name, column_name, type = nil, **kwargs)
+            if type == :text
+              limit = kwargs.delete(:limit)
+              unique = kwargs.delete(:unique)
+
+              if limit
+                quoted_column_name = quote_column_name(column_name)
+                name = text_limit_name(table_name, column_name)
+                definition = "char_length(#{quoted_column_name}) <= #{limit}"
+
+                remove_check_constraint(table_name, definition, name: name)
+              end
+
+              if unique.is_a?(Hash)
+                quoted_column_name ||= quote_column_name(column_name)
+                index_column = column_name
+                unique[:where] = "#{column_name} IS NOT NULL" if unique.delete(:allow_nil_duplicate)
+                index_column = "LOWER(#{quoted_column_name})" if unique.delete(:case_insensitive)
+
+                remove_index table_name, index_column, unique: true, **unique
+              elsif unique
+                remove_index table_name, column_name, unique: unique
+              end
+            end
+
+            super
+          end
+        end
+      end
+    end
+  end
+end