diff options
5 files changed, 64 insertions, 2 deletions
diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md index 8cedfd5277..87420a0746 100644 --- a/activerecord/CHANGELOG.md +++ b/activerecord/CHANGELOG.md @@ -1,3 +1,9 @@ +* Version the API presented to migration classes, so we can change parameter + defaults without breaking existing migrations, or forcing them to be + rewritten through a deprecation cycle. + + *Matthew Draper*, *Ravil Bayramgalin* + * Use bind params for `limit` and `offset`. This will generate significantly fewer prepared statements for common tasks like pagination. To support this change, passing a string containing a comma to `limit` has been deprecated, diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb index ca2537cdc3..53a84c1342 100644 --- a/activerecord/lib/active_record/migration.rb +++ b/activerecord/lib/active_record/migration.rb @@ -476,6 +476,32 @@ module ActiveRecord # are in a Migration with <tt>self.disable_ddl_transaction!</tt>. class Migration autoload :CommandRecorder, 'active_record/migration/command_recorder' + autoload :Compatibility, 'active_record/migration/compatibility' + + # This must be defined before the inherited hook, below + class Current < Migration # :nodoc: + end + + def self.inherited(subclass) # :nodoc: + super + if subclass.superclass == Migration + subclass.include Compatibility::Legacy + end + end + + def self.[](version) + version = version.to_s + name = "V#{version.tr('.', '_')}" + unless Compatibility.const_defined?(name) + versions = Compatibility.constants.grep(/\AV[0-9_]+\z/).map { |s| s.to_s.delete('V').tr('_', '.').inspect } + raise "Unknown migration version #{version.inspect}; expected one of #{versions.sort.join(', ')}" + end + Compatibility.const_get(name) + end + + def self.current_version + Rails.version.to_f + end MigrationFilenameRegexp = /\A([0-9]+)_([_a-z0-9]*)\.?([_a-z0-9]*)?\.rb\z/ # :nodoc: diff --git a/activerecord/lib/active_record/migration/compatibility.rb b/activerecord/lib/active_record/migration/compatibility.rb new file mode 100644 index 0000000000..71d702e812 --- /dev/null +++ b/activerecord/lib/active_record/migration/compatibility.rb @@ -0,0 +1,30 @@ +module ActiveRecord + class Migration + module Compatibility # :nodoc: all + V5_0 = Current + + module FourTwoShared + end + + class V4_2 < V5_0 + # 4.2 is defined as a module because it needs to be shared with + # Legacy. When the time comes, V5_0 should be defined straight + # in its class. + include FourTwoShared + end + + module Legacy + include FourTwoShared + + def run(*) + ActiveSupport::Deprecation.warn \ + "Directly inheriting from ActiveRecord::Migration is deprecated. " \ + "Please specify the Rails release the migration was written for:\n" \ + "\n" \ + " class #{self.class.name} < ActiveRecord::Migration[4.2]" + super + end + end + end + end +end diff --git a/activerecord/lib/rails/generators/active_record/migration/templates/create_table_migration.rb b/activerecord/lib/rails/generators/active_record/migration/templates/create_table_migration.rb index fadab2a1e6..5f7201cfe1 100644 --- a/activerecord/lib/rails/generators/active_record/migration/templates/create_table_migration.rb +++ b/activerecord/lib/rails/generators/active_record/migration/templates/create_table_migration.rb @@ -1,4 +1,4 @@ -class <%= migration_class_name %> < ActiveRecord::Migration +class <%= migration_class_name %> < ActiveRecord::Migration[<%= ActiveRecord::Migration.current_version %>] def change create_table :<%= table_name %><%= primary_key_type %> do |t| <% attributes.each do |attribute| -%> diff --git a/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb b/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb index 23a377db6a..107f107dc4 100644 --- a/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb +++ b/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb @@ -1,4 +1,4 @@ -class <%= migration_class_name %> < ActiveRecord::Migration +class <%= migration_class_name %> < ActiveRecord::Migration[<%= ActiveRecord::Migration.current_version %>] <%- if migration_action == 'add' -%> def change <% attributes.each do |attribute| -%> |