118 lines
2.6 KiB
Ruby
118 lines
2.6 KiB
Ruby
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require 'spec_helper'
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require 'logger'
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describe 'null object mimicking a class' do
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class User
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def login
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'bob'
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end
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end
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module Authorizable
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def authorized_for?(object)
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true
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end
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end
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class LibraryPatron < User
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include Authorizable
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def member?
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true
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end
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def name
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'Bob'
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end
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def notify_of_overdue_books(titles)
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puts 'Notifying...'
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end
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end
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subject(:null) { mimic_class.new }
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let(:mimic_class) do
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Naught.build do |b|
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b.mimic LibraryPatron
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end
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end
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it 'responds to all methods defined on the target class' do
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expect(null.member?).to be_nil
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expect(null.name).to be_nil
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expect(null.notify_of_overdue_books(['The Grapes of Wrath'])).to be_nil
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end
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it 'does not respond to methods not defined on the target class' do
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expect { null.foobar }.to raise_error(NoMethodError)
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end
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it 'reports which messages it does and does not respond to' do
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expect(null).to respond_to(:member?)
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expect(null).to respond_to(:name)
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expect(null).to respond_to(:notify_of_overdue_books)
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expect(null).not_to respond_to(:foobar)
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end
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it 'has an informative inspect string' do
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expect(null.inspect).to eq('<null:LibraryPatron>')
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end
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it 'excludes Object methods from being mimicked' do
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expect(null.object_id).not_to be_nil
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expect(null.hash).not_to be_nil
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end
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it 'includes inherited methods' do
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expect(null.authorized_for?('something')).to be_nil
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expect(null.login).to be_nil
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end
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describe 'with include_super: false' do
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let(:mimic_class) do
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Naught.build do |b|
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b.mimic LibraryPatron, :include_super => false
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end
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end
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it 'excludes inherited methods' do
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expect(null).to_not respond_to(:authorized_for?)
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expect(null).to_not respond_to(:login)
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end
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end
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end
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describe 'using mimic with black_hole' do
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subject(:null) { mimic_class.new }
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let(:mimic_class) do
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Naught.build do |b|
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b.mimic Logger
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b.black_hole
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end
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end
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def self.it_behaves_like_a_black_hole_mimic
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it 'returns self from mimicked methods' do
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expect(null.info).to equal(null)
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expect(null.error).to equal(null)
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expect(null << 'test').to equal(null)
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end
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it 'does not respond to methods not defined on the target class' do
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expect { null.foobar }.to raise_error(NoMethodError)
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end
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end
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it_behaves_like_a_black_hole_mimic
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describe '(reverse order)' do
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let(:mimic_class) do
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Naught.build do |b|
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b.black_hole
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b.mimic Logger
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end
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end
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it_behaves_like_a_black_hole_mimic
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end
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end
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