NamedFunction cannot be used for ordering anymore in arel 6

[fschwahn]

Hi,
with arel 5 I could do the following:

t = Arel::Table.new(:table)
Arel::Nodes::NamedFunction.new('CAST', [t[:date].as("TIME")]).desc

Which would allow me to order according to a named function. This does not work in arel 6 anymore:

undefined method `asc' for #<Arel::Nodes::NamedFunction:0x007fc858b977d8> (NoMethodError)

Is there any reason this functionality was removed, or is this a regression?

The following can be used to reproduce:

#!/usr/bin/env ruby

begin
  require 'bundler/inline'
rescue LoadError => e
  $stderr.puts 'Bundler version 1.10 or later is required. Please update your Bundler'
  raise e
end

gemfile(true) do
  source 'https://rubygems.org'
  gem 'sqlite3'

  # Arel 6
  gem 'activerecord', '~> 4.2', require: 'active_record'
  gem 'arel', '~> 6.0'

  # Arel 5
  # gem 'activerecord', '~> 4.1', require: 'active_record'
  # gem 'arel', '~> 5.0'
end

ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")

t = Arel::Table.new(:table, ActiveRecord::Base)
puts Arel::Nodes::NamedFunction.new('CAST', [t[:date].as("TIME")]).desc.to_sql

All the best,
Fabian

[vipulnsward]

Looks like a regression.
Arel::Expression was deprecated and removed. The desc, asc calls were being imported from Arel::OrderPredications into Arel::Expression and later to NamedFunction.

You can import OrderPredications manually though. I don't think there's a need to import in in NamedFunction right now.

[fschwahn]

@vipulnsward Thank you for your answer, I manually imported Arel::OrderPredications into Arel::Nodes::NamedFunction and it works perfectly.

I'm not sure if this issue should be closed, as it seems to be a regression. Maybe documenting it somewhere would be enough?

[carsonreinke]

Fix here #381