diff options
Diffstat (limited to 'activerecord/lib/active_record/migration/command_recorder.rb')
| -rw-r--r-- | activerecord/lib/active_record/migration/command_recorder.rb | 41 |
1 files changed, 30 insertions, 11 deletions
diff --git a/activerecord/lib/active_record/migration/command_recorder.rb b/activerecord/lib/active_record/migration/command_recorder.rb index dcc2362397..0fa665c7e0 100644 --- a/activerecord/lib/active_record/migration/command_recorder.rb +++ b/activerecord/lib/active_record/migration/command_recorder.rb @@ -5,15 +5,36 @@ module ActiveRecord # knows how to invert the following commands: # # * add_column + # * add_foreign_key # * add_index + # * add_reference # * add_timestamps - # * create_table + # * change_column + # * change_column_default (must supply a :from and :to option) + # * change_column_null # * create_join_table + # * create_table + # * disable_extension + # * drop_join_table + # * drop_table (must supply a block) + # * enable_extension + # * remove_column (must supply a type) + # * remove_columns (must specify at least one column name or more) + # * remove_foreign_key (must supply a second table) + # * remove_index + # * remove_reference # * remove_timestamps # * rename_column # * rename_index # * rename_table class CommandRecorder + ReversibleAndIrreversibleMethods = [:create_table, :create_join_table, :rename_table, :add_column, :remove_column, + :rename_index, :rename_column, :add_index, :remove_index, :add_timestamps, :remove_timestamps, + :change_column_default, :add_reference, :remove_reference, :transaction, + :drop_join_table, :drop_table, :execute_block, :enable_extension, :disable_extension, + :change_column, :execute, :remove_columns, :change_column_null, + :add_foreign_key, :remove_foreign_key + ] include JoinTable attr_accessor :commands, :delegate, :reverting @@ -41,7 +62,7 @@ module ActiveRecord @reverting = !@reverting end - # record +command+. +command+ should be a method name and arguments. + # Record +command+. +command+ should be a method name and arguments. # For example: # # recorder.record(:method_name, [:arg1, :arg2]) @@ -62,7 +83,12 @@ module ActiveRecord # invert the +command+. def inverse_of(command, args, &block) method = :"invert_#{command}" - raise IrreversibleMigration unless respond_to?(method, true) + raise IrreversibleMigration, <<-MSG.strip_heredoc unless respond_to?(method, true) + This migration uses #{command}, which is not automatically reversible. + To make the migration reversible you can either: + 1. Define #up and #down methods in place of the #change method. + 2. Use the #reversible method to define reversible behavior. + MSG send(method, args, &block) end @@ -70,14 +96,7 @@ module ActiveRecord super || delegate.respond_to?(*args) end - [:create_table, :create_join_table, :rename_table, :add_column, :remove_column, - :rename_index, :rename_column, :add_index, :remove_index, :add_timestamps, :remove_timestamps, - :add_reference, :remove_reference, :transaction, - :drop_join_table, :drop_table, :execute_block, :enable_extension, - :change_column, :execute, :remove_columns, :change_column_null, - :add_foreign_key, :remove_foreign_key - # irreversible methods need to be here too - ].each do |method| + ReversibleAndIrreversibleMethods.each do |method| class_eval <<-EOV, __FILE__, __LINE__ + 1 def #{method}(*args, &block) # def create_table(*args, &block) record(:"#{method}", args, &block) # record(:create_table, args, &block) |