Class: Dataset::Block

Inherits:
Base
  • Object
show all
Includes:
InstanceMethods
Defined in:
lib/dataset/base.rb

Overview

The easiest way to create some data before a suite of tests is run is by using a Dataset::Block. An example works wonders:

class PeopleTest < Test::Unit::TestCase
 dataset do
   create_record :person, :billy, :name => 'Billy'
 end
       
 def test_name
   assert_equal 'Billy', people(:billy).name
 end
end

The database will be cleared and billy will be inserted once before running each of the tests within a transaction. All the normal transaction fixtures stuff will still work.

One of the great features of Dataset, at least when things get really interesting in your data needs, is that nested contexts will be additive. Consider this:

describe Something do
 dataset :a              => Dataset :a is loaded (at the right time)
    
 it 'should whatever'
 end
    
 describe More do
   dataset :b            => Dataset :b is loaded. :a data is still there
      
   it 'should'
   end
 end
    
 describe Another do     => Database is restored to :a, without re-running :a logic
   it 'should'
   end
 end
end

Instance Variables

You may also assign instance variables in a dataset block, and they will be available to your test methods. You have to be careful with this in a similar way that you must with an RSpec before :all block. Since the instance variables are pointing to the same instances accross all tests, things can get weird if you intend to change their state. It's best use is for loading objects that you want to read a lot without loading over and over again for each test.

Building on Other Datasets

You may pass any number of Dataset::Base subclasses - or better yet, their names - to the dataset method. When you use a block, this adds a lot of clarity:

class PersonTest < Test::Unit::TestCase
 dataset :organization, :people do
   id = create_record :person, :second_admin, :name => 'Admin Three'
   create_record :organization_administratorship, :organization_id => organization_id(:first_bank), :person_id => id
 end
  
 def test_admins
   assert organizations(:first_bank).admins.include?(people(:second_admin))
 end
end

Reusing a Dataset

When you need to go beyond the block, create a Dataset::Base subclass!

Instance Method Summary collapse

Methods included from InstanceMethods

#extend_from_dataset_load

Methods inherited from Base

helper_methods, helpers, used_datasets, uses

Instance Method Details

#load ⇒ Object

:nodoc:



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# File 'lib/dataset/base.rb', line 151

def load # :nodoc:
  dataset_session_binding.install_block_variables(self)
  doload
  dataset_session_binding.copy_block_variables(self)
end