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|
require_relative '../../spec_helper'
require_relative 'fixtures/classes'
describe "Module#prepend" do
it "is a public method" do
Module.should have_public_instance_method(:prepend, false)
end
it "does not affect the superclass" do
Class.new { prepend Module.new }.superclass.should == Object
end
it "calls #prepend_features(self) in reversed order on each module" do
ScratchPad.record []
m = Module.new do
def self.prepend_features(mod)
ScratchPad << [ self, mod ]
end
end
m2 = Module.new do
def self.prepend_features(mod)
ScratchPad << [ self, mod ]
end
end
m3 = Module.new do
def self.prepend_features(mod)
ScratchPad << [ self, mod ]
end
end
c = Class.new { prepend(m, m2, m3) }
ScratchPad.recorded.should == [ [ m3, c], [ m2, c ], [ m, c ] ]
end
it "updates the method when a module is prepended" do
m_module = Module.new do
def foo
"m"
end
end
a_class = Class.new do
def foo
'a'
end
end
a = a_class.new
foo = -> { a.foo }
foo.call.should == 'a'
a_class.class_eval do
prepend m_module
end
foo.call.should == 'm'
end
it "updates the method when a prepended module is updated" do
m_module = Module.new
a_class = Class.new do
prepend m_module
def foo
'a'
end
end
a = a_class.new
foo = -> { a.foo }
foo.call.should == 'a'
m_module.module_eval do
def foo
"m"
end
end
foo.call.should == 'm'
end
it "updates the method when there is a base included method and the prepended module overrides it" do
base_module = Module.new do
def foo
'a'
end
end
a_class = Class.new do
include base_module
end
a = a_class.new
foo = -> { a.foo }
foo.call.should == 'a'
m_module = Module.new do
def foo
"m"
end
end
a_class.prepend m_module
foo.call.should == 'm'
end
it "updates the method when there is a base included method and the prepended module is later updated" do
base_module = Module.new do
def foo
'a'
end
end
a_class = Class.new do
include base_module
end
a = a_class.new
foo = -> { a.foo }
foo.call.should == 'a'
m_module = Module.new
a_class.prepend m_module
foo.call.should == 'a'
m_module.module_eval do
def foo
"m"
end
end
foo.call.should == 'm'
end
it "updates the method when a module prepended after a call is later updated" do
m_module = Module.new
a_class = Class.new do
def foo
'a'
end
end
a = a_class.new
foo = -> { a.foo }
foo.call.should == 'a'
a_class.prepend m_module
foo.call.should == 'a'
m_module.module_eval do
def foo
"m"
end
end
foo.call.should == 'm'
end
it "updates the method when a module is prepended after another and the method is defined later on that module" do
m_module = Module.new do
def foo
'a'
end
end
a_class = Class.new
a_class.prepend m_module
a = a_class.new
foo = -> { a.foo }
foo.call.should == 'a'
n_module = Module.new
a_class.prepend n_module
foo.call.should == 'a'
n_module.module_eval do
def foo
"n"
end
end
foo.call.should == 'n'
end
it "updates the method when a module is included in a prepended module and the method is defined later" do
a_class = Class.new
base_module = Module.new do
def foo
'a'
end
end
a_class.prepend base_module
a = a_class.new
foo = -> { a.foo }
foo.call.should == 'a'
m_module = Module.new
n_module = Module.new
m_module.include n_module
a_class.prepend m_module
n_module.module_eval do
def foo
"n"
end
end
foo.call.should == 'n'
end
it "updates the method when a new module with an included module is prepended" do
a_class = Class.new do
def foo
'a'
end
end
n_module = Module.new do
def foo
'n'
end
end
m_module = Module.new do
include n_module
end
a = a_class.new
foo = -> { a.foo }
foo.call.should == 'a'
a_class.class_eval do
prepend m_module
end
foo.call.should == 'n'
end
it "updates the constant when a module is prepended" do
module ModuleSpecs::ConstUpdatePrepended
module M
FOO = 'm'
end
module A
FOO = 'a'
end
module B
include A
def self.foo
FOO
end
end
B.foo.should == 'a'
B.prepend M
B.foo.should == 'm'
end
end
it "updates the constant when a prepended module is updated" do
module ModuleSpecs::ConstPrependedUpdated
module M
end
module A
FOO = 'a'
end
module B
include A
prepend M
def self.foo
FOO
end
end
B.foo.should == 'a'
M.const_set(:FOO, 'm')
B.foo.should == 'm'
end
end
it "updates the constant when there is a base included constant and the prepended module overrides it" do
module ModuleSpecs::ConstIncludedPrependedOverride
module Base
FOO = 'a'
end
module A
include Base
def self.foo
FOO
end
end
A.foo.should == 'a'
module M
FOO = 'm'
end
A.prepend M
A.foo.should == 'm'
end
end
it "updates the constant when there is a base included constant and the prepended module is later updated" do
module ModuleSpecs::ConstIncludedPrependedLaterUpdated
module Base
FOO = 'a'
end
module A
include Base
def self.foo
FOO
end
end
A.foo.should == 'a'
module M
end
A.prepend M
A.foo.should == 'a'
M.const_set(:FOO, 'm')
A.foo.should == 'm'
end
end
it "updates the constant when a module prepended after a constant is later updated" do
module ModuleSpecs::ConstUpdatedPrependedAfterLaterUpdated
module M
end
module A
FOO = 'a'
end
module B
include A
def self.foo
FOO
end
end
B.foo.should == 'a'
B.prepend M
B.foo.should == 'a'
M.const_set(:FOO, 'm')
B.foo.should == 'm'
end
end
it "updates the constant when a module is prepended after another and the constant is defined later on that module" do
module ModuleSpecs::ConstUpdatedPrependedAfterConstDefined
module M
FOO = 'm'
end
module A
prepend M
def self.foo
FOO
end
end
A.foo.should == 'm'
module N
end
A.prepend N
A.foo.should == 'm'
N.const_set(:FOO, 'n')
A.foo.should == 'n'
end
end
it "updates the constant when a module is included in a prepended module and the constant is defined later" do
module ModuleSpecs::ConstUpdatedIncludedInPrependedConstDefinedLater
module A
def self.foo
FOO
end
end
module Base
FOO = 'a'
end
A.prepend Base
A.foo.should == 'a'
module N
end
module M
include N
end
A.prepend M
N.const_set(:FOO, 'n')
A.foo.should == 'n'
end
end
it "updates the constant when a new module with an included module is prepended" do
module ModuleSpecs::ConstUpdatedNewModuleIncludedPrepended
module A
FOO = 'a'
end
module B
include A
def self.foo
FOO
end
end
module N
FOO = 'n'
end
module M
include N
end
B.foo.should == 'a'
B.prepend M
B.foo.should == 'n'
end
end
it "raises a TypeError when the argument is not a Module" do
-> { ModuleSpecs::Basic.prepend(Class.new) }.should raise_error(TypeError)
end
it "does not raise a TypeError when the argument is an instance of a subclass of Module" do
-> { ModuleSpecs::SubclassSpec.prepend(ModuleSpecs::Subclass.new) }.should_not raise_error(TypeError)
end
it "imports constants" do
m1 = Module.new
m1::MY_CONSTANT = 1
m2 = Module.new { prepend(m1) }
m2.constants.should include(:MY_CONSTANT)
end
it "imports instance methods" do
Module.new { prepend ModuleSpecs::A }.instance_methods.should include(:ma)
end
it "does not import methods to modules and classes" do
Module.new { prepend ModuleSpecs::A }.methods.should_not include(:ma)
end
it "allows wrapping methods" do
m = Module.new { def calc(x) super + 3 end }
c = Class.new { def calc(x) x*2 end }
c.prepend(m)
c.new.calc(1).should == 5
end
it "also prepends included modules" do
a = Module.new { def calc(x) x end }
b = Module.new { include a }
c = Class.new { prepend b }
c.new.calc(1).should == 1
end
it "prepends multiple modules in the right order" do
m1 = Module.new { def chain; super << :m1; end }
m2 = Module.new { def chain; super << :m2; end; prepend(m1) }
c = Class.new { def chain; [:c]; end; prepend(m2) }
c.new.chain.should == [:c, :m2, :m1]
end
it "includes prepended modules in ancestors" do
m = Module.new
Class.new { prepend(m) }.ancestors.should include(m)
end
it "reports the prepended module as the method owner" do
m = Module.new { def meth; end }
c = Class.new { def meth; end; prepend(m) }
c.new.method(:meth).owner.should == m
end
it "reports the prepended module as the unbound method owner" do
m = Module.new { def meth; end }
c = Class.new { def meth; end; prepend(m) }
c.instance_method(:meth).owner.should == m
c.public_instance_method(:meth).owner.should == m
end
it "causes the prepended module's method to be aliased by alias_method" do
m = Module.new { def meth; :m end }
c = Class.new { def meth; :c end; prepend(m); alias_method :alias, :meth }
c.new.alias.should == :m
end
it "reports the class for the owner of an aliased method on the class" do
m = Module.new
c = Class.new { prepend(m); def meth; :c end; alias_method :alias, :meth }
c.instance_method(:alias).owner.should == c
end
it "reports the class for the owner of a method aliased from the prepended module" do
m = Module.new { def meth; :m end }
c = Class.new { prepend(m); alias_method :alias, :meth }
c.instance_method(:alias).owner.should == c
end
it "sees an instance of a prepended class as kind of the prepended module" do
m = Module.new
c = Class.new { prepend(m) }
c.new.should be_kind_of(m)
end
it "keeps the module in the chain when dupping the class" do
m = Module.new
c = Class.new { prepend(m) }
c.dup.new.should be_kind_of(m)
end
ruby_version_is ''...'3.0' do
it "keeps the module in the chain when dupping an intermediate module" do
m1 = Module.new { def calc(x) x end }
m2 = Module.new { prepend(m1) }
c1 = Class.new { prepend(m2) }
m2dup = m2.dup
m2dup.ancestors.should == [m2dup,m1,m2]
c2 = Class.new { prepend(m2dup) }
c1.ancestors[0,3].should == [m1,m2,c1]
c1.new.should be_kind_of(m1)
c2.ancestors[0,4].should == [m2dup,m1,m2,c2]
c2.new.should be_kind_of(m1)
end
end
ruby_version_is '3.0' do
it "uses only new module when dupping the module" do
m1 = Module.new { def calc(x) x end }
m2 = Module.new { prepend(m1) }
c1 = Class.new { prepend(m2) }
m2dup = m2.dup
m2dup.ancestors.should == [m1,m2dup]
c2 = Class.new { prepend(m2dup) }
c1.ancestors[0,3].should == [m1,m2,c1]
c1.new.should be_kind_of(m1)
c2.ancestors[0,3].should == [m1,m2dup,c2]
c2.new.should be_kind_of(m1)
end
end
it "depends on prepend_features to add the module" do
m = Module.new { def self.prepend_features(mod) end }
Class.new { prepend(m) }.ancestors.should_not include(m)
end
it "adds the module in the subclass chains" do
parent = Class.new { def chain; [:parent]; end }
child = Class.new(parent) { def chain; super << :child; end }
mod = Module.new { def chain; super << :mod; end }
parent.prepend(mod)
parent.ancestors[0,2].should == [mod, parent]
child.ancestors[0,3].should == [child, mod, parent]
parent.new.chain.should == [:parent, :mod]
child.new.chain.should == [:parent, :mod, :child]
end
it "inserts a later prepended module into the chain" do
m1 = Module.new { def chain; super << :m1; end }
m2 = Module.new { def chain; super << :m2; end }
c1 = Class.new { def chain; [:c1]; end; prepend m1 }
c2 = Class.new(c1) { def chain; super << :c2; end }
c2.new.chain.should == [:c1, :m1, :c2]
c1.prepend(m2)
c2.new.chain.should == [:c1, :m1, :m2, :c2]
end
it "works with subclasses" do
m = Module.new do
def chain
super << :module
end
end
c = Class.new do
prepend m
def chain
[:class]
end
end
s = Class.new(c) do
def chain
super << :subclass
end
end
s.new.chain.should == [:class, :module, :subclass]
end
it "throws a NoMethodError when there is no more superclass" do
m = Module.new do
def chain
super << :module
end
end
c = Class.new do
prepend m
def chain
super << :class
end
end
-> { c.new.chain }.should raise_error(NoMethodError)
end
it "calls prepended after prepend_features" do
ScratchPad.record []
m = Module.new do
def self.prepend_features(klass)
ScratchPad << [:prepend_features, klass]
end
def self.prepended(klass)
ScratchPad << [:prepended, klass]
end
end
c = Class.new { prepend(m) }
ScratchPad.recorded.should == [[:prepend_features, c], [:prepended, c]]
end
it "prepends a module if it is included in a super class" do
module ModuleSpecs::M3
module M; end
class A; include M; end
class B < A; prepend M; end
all = [A, B, M]
(B.ancestors.filter { |a| all.include?(a) }).should == [M, B, A, M]
end
end
it "detects cyclic prepends" do
-> {
module ModuleSpecs::P
prepend ModuleSpecs::P
end
}.should raise_error(ArgumentError)
end
it "doesn't accept no-arguments" do
-> {
Module.new do
prepend
end
}.should raise_error(ArgumentError)
end
it "returns the class it's included into" do
m = Module.new
r = nil
c = Class.new { r = prepend m }
r.should == c
end
it "clears any caches" do
module ModuleSpecs::M3
module PM1
def foo
:m1
end
end
module PM2
def foo
:m2
end
end
klass = Class.new do
prepend PM1
def get
foo
end
end
o = klass.new
o.get.should == :m1
klass.class_eval do
prepend PM2
end
o.get.should == :m2
end
end
it "supports super when the module is prepended into a singleton class" do
ScratchPad.record []
mod = Module.new do
def self.inherited(base)
super
end
end
module_with_singleton_class_prepend = Module.new do
singleton_class.prepend(mod)
end
klass = Class.new(ModuleSpecs::RecordIncludedModules) do
include module_with_singleton_class_prepend
end
ScratchPad.recorded.should == klass
end
it "supports super when the module is prepended into a singleton class with a class super" do
ScratchPad.record []
base_class = Class.new(ModuleSpecs::RecordIncludedModules) do
def self.inherited(base)
super
end
end
prepended_module = Module.new
base_class.singleton_class.prepend(prepended_module)
child_class = Class.new(base_class)
ScratchPad.recorded.should == child_class
end
it "does not interfere with a define_method super in the original class" do
base_class = Class.new do
def foo(ary)
ary << 1
end
end
child_class = Class.new(base_class) do
define_method :foo do |ary|
ary << 2
super(ary)
end
end
prep_mod = Module.new do
def foo(ary)
ary << 3
super(ary)
end
end
child_class.prepend(prep_mod)
ary = []
child_class.new.foo(ary)
ary.should == [3, 2, 1]
end
describe "called on a module" do
describe "included into a class"
it "does not obscure the module's methods from reflective access" do
mod = Module.new do
def foo; end
end
cls = Class.new do
include mod
end
pre = Module.new
mod.prepend pre
cls.instance_methods.should include(:foo)
end
end
end
|