gitlab-org--gitlab-foss/spec/models/concerns/each_batch_spec.rb
Yorick Peterse ff78af152c
Added EachBatch for iterating tables in batches
This module provides a class method called `each_batch` that can be used
to iterate tables in batches in a more efficient way compared to Rails'
`in_batches` method. This commit also includes a RuboCop cop to
blacklist the use of `in_batches` in favour of this new method.
2017-07-07 16:39:36 +02:00

53 lines
1.2 KiB
Ruby

require 'spec_helper'
describe EachBatch do
describe '.each_batch' do
let(:model) do
Class.new(ActiveRecord::Base) do
include EachBatch
self.table_name = 'users'
end
end
before do
5.times { create(:user, updated_at: 1.day.ago) }
end
it 'yields an ActiveRecord::Relation when a block is given' do
model.each_batch do |relation|
expect(relation).to be_a_kind_of(ActiveRecord::Relation)
end
end
it 'yields a batch index as the second argument' do
model.each_batch do |_, index|
expect(index).to eq(1)
end
end
it 'accepts a custom batch size' do
amount = 0
model.each_batch(of: 1) { amount += 1 }
expect(amount).to eq(5)
end
it 'does not include ORDER BYs in the yielded relations' do
model.each_batch do |relation|
expect(relation.to_sql).not_to include('ORDER BY')
end
end
it 'allows updating of the yielded relations' do
time = Time.now
model.each_batch do |relation|
relation.update_all(updated_at: time)
end
expect(model.where(updated_at: time).count).to eq(5)
end
end
end