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require 'abstract_unit'
require 'active_support/core_ext/module'
module One
Constant1 = "Hello World"
Constant2 = "What's up?"
end
class Ab
include One
Constant1 = "Hello World" # Will have different object id than One::Constant1
Constant3 = "Goodbye World"
end
module Xy
class Bc
include One
end
end
module Yz
module Zy
class Cd
include One
end
end
end
Somewhere = Struct.new(:street, :city) do
protected
def protected_method
end
private
def private_method
end
end
class Someone < Struct.new(:name, :place)
delegate :street, :city, :to_f, :protected_method, :private_method, :to => :place
delegate :upcase, :to => "place.city"
FAILED_DELEGATE_LINE = __LINE__ + 1
delegate :foo, :to => :place
end
Invoice = Struct.new(:client) do
delegate :street, :city, :name, :to => :client, :prefix => true
delegate :street, :city, :name, :to => :client, :prefix => :customer
end
Project = Struct.new(:description, :person) do
delegate :name, :to => :person, :allow_nil => true
delegate :to_f, :to => :description, :allow_nil => true
end
Developer = Struct.new(:client) do
delegate :name, :to => :client, :prefix => nil
end
Tester = Struct.new(:client) do
delegate :name, :to => :client, :prefix => false
end
class Name
delegate :upcase, :to => :@full_name
def initialize(first, last)
@full_name = "#{first} #{last}"
end
end
class ModuleTest < Test::Unit::TestCase
def setup
@david = Someone.new("David", Somewhere.new("Paulina", "Chicago"))
end
def test_delegation_to_methods
assert_equal "Paulina", @david.street
assert_equal "Chicago", @david.city
end
def test_delegation_to_protected_method
assert_raise(NoMethodError) { @david.protected_method }
end
def test_delegation_to_private_method
assert_raise(NoMethodError) { @david.private_method }
end
def test_delegation_down_hierarchy
assert_equal "CHICAGO", @david.upcase
end
def test_delegation_to_instance_variable
david = Name.new("David", "Hansson")
assert_equal "DAVID HANSSON", david.upcase
end
def test_missing_delegation_target
assert_raise(ArgumentError) do
Name.send :delegate, :nowhere
end
assert_raise(ArgumentError) do
Name.send :delegate, :noplace, :tos => :hollywood
end
end
def test_delegation_prefix
invoice = Invoice.new(@david)
assert_equal invoice.client_name, "David"
assert_equal invoice.client_street, "Paulina"
assert_equal invoice.client_city, "Chicago"
end
def test_delegation_custom_prefix
invoice = Invoice.new(@david)
assert_equal invoice.customer_name, "David"
assert_equal invoice.customer_street, "Paulina"
assert_equal invoice.customer_city, "Chicago"
end
def test_delegation_prefix_with_nil_or_false
assert_equal Developer.new(@david).name, "David"
assert_equal Tester.new(@david).name, "David"
end
def test_delegation_prefix_with_instance_variable
assert_raise ArgumentError do
Class.new do
def initialize(client)
@client = client
end
delegate :name, :address, :to => :@client, :prefix => true
end
end
end
def test_delegation_with_allow_nil
rails = Project.new("Rails", Someone.new("David"))
assert_equal rails.name, "David"
end
def test_delegation_with_allow_nil_and_nil_value
rails = Project.new("Rails")
assert_nil rails.name
end
def test_delegation_with_allow_nil_and_nil_value_and_prefix
Project.class_eval do
delegate :name, :to => :person, :allow_nil => true, :prefix => true
end
rails = Project.new("Rails")
assert_nil rails.person_name
end
def test_delegation_without_allow_nil_and_nil_value
david = Someone.new("David")
assert_raise(RuntimeError) { david.street }
end
def test_delegation_to_method_that_exists_on_nil
nil_person = Someone.new(nil)
assert_equal 0.0, nil_person.to_f
end
def test_delegation_to_method_that_exists_on_nil_when_allowing_nil
nil_project = Project.new(nil)
assert_equal 0.0, nil_project.to_f
end
def test_delegation_does_not_raise_error_when_removing_singleton_instance_methods
parent = Class.new do
def self.parent_method; end
end
assert_nothing_raised do
Class.new(parent) do
class << self
delegate :parent_method, :to => :superclass
end
end
end
end
def test_delegation_exception_backtrace
someone = Someone.new("foo", "bar")
someone.foo
rescue NoMethodError => e
file_and_line = "#{__FILE__}:#{Someone::FAILED_DELEGATE_LINE}"
assert e.backtrace.first.include?(file_and_line),
"[#{e.backtrace.first}] did not include [#{file_and_line}]"
end
def test_parent
assert_equal Yz::Zy, Yz::Zy::Cd.parent
assert_equal Yz, Yz::Zy.parent
assert_equal Object, Yz.parent
end
def test_parents
assert_equal [Yz::Zy, Yz, Object], Yz::Zy::Cd.parents
assert_equal [Yz, Object], Yz::Zy.parents
end
def test_local_constants
assert_equal %w(Constant1 Constant3), Ab.local_constants.sort.map(&:to_s)
end
end
module BarMethodAliaser
def self.included(foo_class)
foo_class.class_eval do
include BarMethods
alias_method_chain :bar, :baz
end
end
end
module BarMethods
def bar_with_baz
bar_without_baz << '_with_baz'
end
def quux_with_baz!
quux_without_baz! << '_with_baz'
end
def quux_with_baz?
false
end
def quux_with_baz=(v)
send(:quux_without_baz=, v) << '_with_baz'
end
def duck_with_orange
duck_without_orange << '_with_orange'
end
end
class MethodAliasingTest < Test::Unit::TestCase
def setup
Object.const_set :FooClassWithBarMethod, Class.new { def bar() 'bar' end }
@instance = FooClassWithBarMethod.new
end
def teardown
Object.instance_eval { remove_const :FooClassWithBarMethod }
end
def test_alias_method_chain
assert @instance.respond_to?(:bar)
feature_aliases = [:bar_with_baz, :bar_without_baz]
feature_aliases.each do |method|
assert !@instance.respond_to?(method)
end
assert_equal 'bar', @instance.bar
FooClassWithBarMethod.class_eval { include BarMethodAliaser }
feature_aliases.each do |method|
assert_respond_to @instance, method
end
assert_equal 'bar_with_baz', @instance.bar
assert_equal 'bar', @instance.bar_without_baz
end
def test_alias_method_chain_with_punctuation_method
FooClassWithBarMethod.class_eval do
def quux!; 'quux' end
end
assert !@instance.respond_to?(:quux_with_baz!)
FooClassWithBarMethod.class_eval do
include BarMethodAliaser
alias_method_chain :quux!, :baz
end
assert_respond_to @instance, :quux_with_baz!
assert_equal 'quux_with_baz', @instance.quux!
assert_equal 'quux', @instance.quux_without_baz!
end
def test_alias_method_chain_with_same_names_between_predicates_and_bang_methods
FooClassWithBarMethod.class_eval do
def quux!; 'quux!' end
def quux?; true end
def quux=(v); 'quux=' end
end
assert !@instance.respond_to?(:quux_with_baz!)
assert !@instance.respond_to?(:quux_with_baz?)
assert !@instance.respond_to?(:quux_with_baz=)
FooClassWithBarMethod.class_eval { include BarMethodAliaser }
assert_respond_to @instance, :quux_with_baz!
assert_respond_to @instance, :quux_with_baz?
assert_respond_to @instance, :quux_with_baz=
FooClassWithBarMethod.alias_method_chain :quux!, :baz
assert_equal 'quux!_with_baz', @instance.quux!
assert_equal 'quux!', @instance.quux_without_baz!
FooClassWithBarMethod.alias_method_chain :quux?, :baz
assert_equal false, @instance.quux?
assert_equal true, @instance.quux_without_baz?
FooClassWithBarMethod.alias_method_chain :quux=, :baz
assert_equal 'quux=_with_baz', @instance.send(:quux=, 1234)
assert_equal 'quux=', @instance.send(:quux_without_baz=, 1234)
end
def test_alias_method_chain_with_feature_punctuation
FooClassWithBarMethod.class_eval do
def quux; 'quux' end
def quux?; 'quux?' end
include BarMethodAliaser
alias_method_chain :quux, :baz!
end
assert_nothing_raised do
assert_equal 'quux_with_baz', @instance.quux_with_baz!
end
assert_raise(NameError) do
FooClassWithBarMethod.alias_method_chain :quux?, :baz!
end
end
def test_alias_method_chain_yields_target_and_punctuation
args = nil
FooClassWithBarMethod.class_eval do
def quux?; end
include BarMethods
FooClassWithBarMethod.alias_method_chain :quux?, :baz do |target, punctuation|
args = [target, punctuation]
end
end
assert_not_nil args
assert_equal 'quux', args[0]
assert_equal '?', args[1]
end
def test_alias_method_chain_preserves_private_method_status
FooClassWithBarMethod.class_eval do
def duck; 'duck' end
include BarMethodAliaser
private :duck
alias_method_chain :duck, :orange
end
assert_raise NoMethodError do
@instance.duck
end
assert_equal 'duck_with_orange', @instance.instance_eval { duck }
assert FooClassWithBarMethod.private_method_defined?(:duck)
end
def test_alias_method_chain_preserves_protected_method_status
FooClassWithBarMethod.class_eval do
def duck; 'duck' end
include BarMethodAliaser
protected :duck
alias_method_chain :duck, :orange
end
assert_raise NoMethodError do
@instance.duck
end
assert_equal 'duck_with_orange', @instance.instance_eval { duck }
assert FooClassWithBarMethod.protected_method_defined?(:duck)
end
def test_alias_method_chain_preserves_public_method_status
FooClassWithBarMethod.class_eval do
def duck; 'duck' end
include BarMethodAliaser
public :duck
alias_method_chain :duck, :orange
end
assert_equal 'duck_with_orange', @instance.duck
assert FooClassWithBarMethod.public_method_defined?(:duck)
end
end
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