Simplify dependencies.rb some. Remove alias of Kernel::Foo to Object::Foo as it was not used and breaks Ruby semantics.

This commit is contained in:
Yehuda Katz 2010-02-14 10:47:50 -08:00
parent d68f8ba5c3
commit 4da45060a2
2 changed files with 142 additions and 202 deletions

View File

@ -1,5 +1,6 @@
require 'set'
require 'thread'
require 'pathname'
require 'active_support/core_ext/module/aliasing'
require 'active_support/core_ext/module/attribute_accessors'
require 'active_support/core_ext/module/introspection'
@ -58,37 +59,105 @@ module ActiveSupport #:nodoc:
mattr_accessor :log_activity
self.log_activity = false
class WatchStack < Array
def initialize
@mutex = Mutex.new
end
def self.locked(*methods)
methods.each { |m| class_eval "def #{m}(*) lock { super } end" }
end
def get(key)
(val = assoc(key)) ? val[1] : []
end
locked :concat, :each, :delete_if, :<<
def new_constants_for(frames)
frames.map do |mod_name, prior_constants|
mod = Inflector.constantize(mod_name)
next unless mod.is_a?(Module)
new_constants = mod.local_constant_names - prior_constants
get(mod_name).concat(new_constants)
new_constants.map do |suffix|
([mod_name, suffix] - ["Object"]).join("::")
end
end.flatten
end
# Add a set of modules to the watch stack, remembering the initial constants
def add_modules(modules)
list = modules.map do |desc|
name = Dependencies.to_constant_name(desc)
consts = Dependencies.qualified_const_defined?(name) ?
Inflector.constantize(name).local_constant_names : []
[name, consts]
end
concat(list)
list
end
def lock
@mutex.synchronize { yield self }
end
end
# An internal stack used to record which constants are loaded by any block.
mattr_accessor :constant_watch_stack
self.constant_watch_stack = []
mattr_accessor :constant_watch_stack_mutex
self.constant_watch_stack_mutex = Mutex.new
self.constant_watch_stack = WatchStack.new
# Module includes this module
module ModuleConstMissing #:nodoc:
def self.included(base) #:nodoc:
def self.append_features(base)
base.class_eval do
unless defined? const_missing_without_dependencies
alias_method_chain :const_missing, :dependencies
end
# Emulate #exclude via an ivar
return if @_const_missing
@_const_missing = method(:const_missing)
remove_method(:const_missing)
end
super
end
def self.excluded(base) #:nodoc:
def self.exclude_from(base)
base.class_eval do
if defined? const_missing_without_dependencies
undef_method :const_missing
alias_method :const_missing, :const_missing_without_dependencies
undef_method :const_missing_without_dependencies
end
define_method :const_missing, @_const_missing
@_const_missing = nil
end
end
# Use const_missing to autoload associations so we don't have to
# require_association when using single-table inheritance.
def const_missing_with_dependencies(class_id)
ActiveSupport::Dependencies.load_missing_constant self, class_id
def const_missing(const_name, nesting = nil)
klass_name = name.presence || "Object"
if !nesting
# We'll assume that the nesting of Foo::Bar is ["Foo::Bar", "Foo"]
# even though it might not be, such as in the case of
# class Foo::Bar; Baz; end
nesting = []
klass_name.to_s.scan(/::|$/) { nesting.unshift $` }
end
# If there are multiple levels of nesting to search under, the top
# level is the one we want to report as the lookup fail.
error = nil
nesting.each do |namespace|
begin
return Dependencies.load_missing_constant namespace.constantize, const_name
rescue NoMethodError then raise
rescue NameError => e
error ||= e
end
end
# Raise the first error for this set. If this const_missing came from an
# earlier const_missing, this will result in the real error bubbling
# all the way up
raise error
end
def unloadable(const_desc = self)
@ -96,47 +165,10 @@ module ActiveSupport #:nodoc:
end
end
# Class includes this module
module ClassConstMissing #:nodoc:
def const_missing(const_name)
if [Object, Kernel].include?(self) || parent == self
super
else
begin
begin
Dependencies.load_missing_constant self, const_name
rescue NameError
parent.send :const_missing, const_name
end
rescue NameError => e
# Make sure that the name we are missing is the one that caused the error
parent_qualified_name = Dependencies.qualified_name_for parent, const_name
raise unless e.missing_name? parent_qualified_name
qualified_name = Dependencies.qualified_name_for self, const_name
raise NameError.new("uninitialized constant #{qualified_name}").copy_blame!(e)
end
end
end
end
# Object includes this module
module Loadable #:nodoc:
def self.included(base) #:nodoc:
base.class_eval do
unless defined? load_without_new_constant_marking
alias_method_chain :load, :new_constant_marking
end
end
end
def self.excluded(base) #:nodoc:
base.class_eval do
if defined? load_without_new_constant_marking
undef_method :load
alias_method :load, :load_without_new_constant_marking
undef_method :load_without_new_constant_marking
end
end
def self.exclude_from(base)
base.class_eval { define_method(:load, Kernel.instance_method(:load)) }
end
def require_or_load(file_name)
@ -151,26 +183,23 @@ module ActiveSupport #:nodoc:
Dependencies.associate_with(file_name)
end
def load_with_new_constant_marking(file, *extras) #:nodoc:
def load_dependency(file)
if Dependencies.load?
Dependencies.new_constants_in(Object) { load_without_new_constant_marking(file, *extras) }
Dependencies.new_constants_in(Object) { yield }.presence
else
load_without_new_constant_marking(file, *extras)
yield
end
rescue Exception => exception # errors from loading file
exception.blame_file! file
raise
end
def require(file, *extras) #:nodoc:
if Dependencies.load?
Dependencies.new_constants_in(Object) { super }
else
super
end
rescue Exception => exception # errors from required file
exception.blame_file! file
raise
def load(file, *)
load_dependency(file) { super }
end
def require(file, *)
load_dependency(file) { super }
end
# Mark the given constant as unloadable. Unloadable constants are removed each
@ -213,16 +242,15 @@ module ActiveSupport #:nodoc:
end
def hook!
Object.instance_eval { include Loadable }
Module.instance_eval { include ModuleConstMissing }
Class.instance_eval { include ClassConstMissing }
Exception.instance_eval { include Blamable }
Object.class_eval { include Loadable }
Module.class_eval { include ModuleConstMissing }
Exception.class_eval { include Blamable }
true
end
def unhook!
ModuleConstMissing.excluded(Module)
Loadable.excluded(Object)
ModuleConstMissing.exclude_from(Module)
Loadable.exclude_from(Object)
true
end
@ -292,29 +320,22 @@ module ActiveSupport #:nodoc:
# Is the provided constant path defined?
def qualified_const_defined?(path)
raise NameError, "#{path.inspect} is not a valid constant name!" unless
/^(::)?([A-Z]\w*)(::[A-Z]\w*)*$/ =~ path
names = path.sub(/^::/, '').to_s.split('::')
names = path.to_s.split('::')
names.shift if names.first.empty?
# We can't use defined? because it will invoke const_missing for the parent
# of the name we are checking.
names.inject(Object) do |mod, name|
return false unless uninherited_const_defined?(mod, name)
return false unless local_const_defined?(mod, name)
mod.const_get name
end
return true
end
if Module.method(:const_defined?).arity == 1
# Does this module define this constant?
# Wrapper to accomodate changing Module#const_defined? in Ruby 1.9
def uninherited_const_defined?(mod, const)
def local_const_defined?(mod, const)
mod.const_defined?(const)
end
else
def uninherited_const_defined?(mod, const) #:nodoc:
def local_const_defined?(mod, const) #:nodoc:
mod.const_defined?(const, false)
end
end
@ -322,29 +343,20 @@ module ActiveSupport #:nodoc:
# Given +path+, a filesystem path to a ruby file, return an array of constant
# paths which would cause Dependencies to attempt to load this file.
def loadable_constants_for_path(path, bases = load_paths)
path = $1 if path =~ /\A(.*)\.rb\Z/
expanded_path = File.expand_path(path)
expanded_path = Pathname.new(path[/\A(.*?)(\.rb)?\Z/, 1]).expand_path
bases.collect do |root|
expanded_root = File.expand_path(root)
next unless %r{\A#{Regexp.escape(expanded_root)}(/|\\)} =~ expanded_path
nesting = expanded_path[(expanded_root.size)..-1]
nesting = nesting[1..-1] if nesting && nesting[0] == ?/
next if nesting.blank?
nesting_camel = nesting.camelize
begin
qualified_const_defined?(nesting_camel)
rescue NameError
next
end
[ nesting_camel ]
end.compact.flatten.compact.uniq
bases.inject([]) do |paths, root|
expanded_root = Pathname.new(root).expand_path
nesting = expanded_path.relative_path_from(expanded_root).to_s
next paths if nesting =~ /\.\./
paths << nesting.camelize
end.uniq
end
# Search for a file in load_paths matching the provided suffix.
def search_for_file(path_suffix)
path_suffix = "#{path_suffix}.rb" unless path_suffix =~ /\.rb\Z/
path_suffix = path_suffix.sub(/(\.rb)?$/, ".rb")
load_paths.each do |root|
path = File.join(root, path_suffix)
return path if File.file? path
@ -393,7 +405,7 @@ module ActiveSupport #:nodoc:
result = nil
newly_defined_paths = new_constants_in(*parent_paths) do
result = load_without_new_constant_marking path
result = Kernel.load path
end
autoloaded_constants.concat newly_defined_paths unless load_once_path?(path)
@ -405,7 +417,7 @@ module ActiveSupport #:nodoc:
# Return the constant path for the provided parent and constant name.
def qualified_name_for(mod, name)
mod_name = to_constant_name mod
(%w(Object Kernel).include? mod_name) ? name.to_s : "#{mod_name}::#{name}"
mod_name == "Object" ? name.to_s : "#{mod_name}::#{name}"
end
# Load the constant named +const_name+ which is missing from +from_mod+. If
@ -413,38 +425,27 @@ module ActiveSupport #:nodoc:
# using const_missing.
def load_missing_constant(from_mod, const_name)
log_call from_mod, const_name
if from_mod == Kernel
if ::Object.const_defined?(const_name)
log "Returning Object::#{const_name} for Kernel::#{const_name}"
return ::Object.const_get(const_name)
else
log "Substituting Object for Kernel"
from_mod = Object
end
end
# If we have an anonymous module, all we can do is attempt to load from Object.
from_mod = Object if from_mod.name.blank?
unless qualified_const_defined?(from_mod.name) && Inflector.constantize(from_mod.name).object_id == from_mod.object_id
unless qualified_const_defined?(from_mod.name) && Inflector.constantize(from_mod.name).equal?(from_mod)
raise ArgumentError, "A copy of #{from_mod} has been removed from the module tree but is still active!"
end
raise ArgumentError, "#{from_mod} is not missing constant #{const_name}!" if uninherited_const_defined?(from_mod, const_name)
raise ArgumentError, "#{from_mod} is not missing constant #{const_name}!" if local_const_defined?(from_mod, const_name)
qualified_name = qualified_name_for from_mod, const_name
path_suffix = qualified_name.underscore
name_error = NameError.new("uninitialized constant #{qualified_name}")
file_path = search_for_file(path_suffix)
if file_path && ! loaded.include?(File.expand_path(file_path)) # We found a matching file to load
require_or_load file_path
raise LoadError, "Expected #{file_path} to define #{qualified_name}" unless uninherited_const_defined?(from_mod, const_name)
raise LoadError, "Expected #{file_path} to define #{qualified_name}" unless local_const_defined?(from_mod, const_name)
return from_mod.const_get(const_name)
elsif mod = autoload_module!(from_mod, const_name, qualified_name, path_suffix)
return mod
elsif (parent = from_mod.parent) && parent != from_mod &&
! from_mod.parents.any? { |p| uninherited_const_defined?(p, const_name) }
! from_mod.parents.any? { |p| local_const_defined?(p, const_name) }
# If our parents do not have a constant named +const_name+ then we are free
# to attempt to load upwards. If they do have such a constant, then this
# const_missing must be due to from_mod::const_name, which should not
@ -505,79 +506,26 @@ module ActiveSupport #:nodoc:
# and will be removed immediately.
def new_constants_in(*descs)
log_call(*descs)
# Build the watch frames. Each frame is a tuple of
# [module_name_as_string, constants_defined_elsewhere]
watch_frames = descs.collect do |desc|
if desc.is_a? Module
mod_name = desc.name
initial_constants = desc.local_constant_names
elsif desc.is_a?(String) || desc.is_a?(Symbol)
mod_name = desc.to_s
# Handle the case where the module has yet to be defined.
initial_constants = if qualified_const_defined?(mod_name)
Inflector.constantize(mod_name).local_constant_names
else
[]
end
else
raise Argument, "#{desc.inspect} does not describe a module!"
end
[mod_name, initial_constants]
end
constant_watch_stack_mutex.synchronize do
constant_watch_stack.concat watch_frames
end
watch_frames = constant_watch_stack.add_modules(descs)
aborting = true
begin
yield # Now yield to the code that is to define new constants.
aborting = false
ensure
# Find the new constants.
new_constants = watch_frames.collect do |mod_name, prior_constants|
# Module still doesn't exist? Treat it as if it has no constants.
next [] unless qualified_const_defined?(mod_name)
mod = Inflector.constantize(mod_name)
next [] unless mod.is_a? Module
new_constants = mod.local_constant_names - prior_constants
# Make sure no other frames takes credit for these constants.
constant_watch_stack_mutex.synchronize do
constant_watch_stack.each do |frame_name, constants|
constants.concat new_constants if frame_name == mod_name
end
end
new_constants.collect do |suffix|
mod_name == "Object" ? suffix : "#{mod_name}::#{suffix}"
end
end.flatten
new_constants = constant_watch_stack.new_constants_for(watch_frames)
log "New constants: #{new_constants * ', '}"
return new_constants unless aborting
if aborting
log "Error during loading, removing partially loaded constants "
new_constants.each { |name| remove_constant name }
new_constants.clear
end
log "Error during loading, removing partially loaded constants "
new_constants.each {|c| remove_constant(c) }.clear
end
return new_constants
return []
ensure
# Remove the stack frames that we added.
if defined?(watch_frames) && ! watch_frames.blank?
frame_ids = watch_frames.collect { |frame| frame.object_id }
constant_watch_stack_mutex.synchronize do
constant_watch_stack.delete_if do |watch_frame|
frame_ids.include? watch_frame.object_id
end
end
end
watch_frames.each {|f| constant_watch_stack.delete(f) } if watch_frames.present?
end
class LoadingModule #:nodoc:
@ -595,11 +543,11 @@ module ActiveSupport #:nodoc:
# A module, class, symbol, or string may be provided.
def to_constant_name(desc) #:nodoc:
name = case desc
when String then desc.starts_with?('::') ? desc[2..-1] : desc
when String then desc.sub(/^::/, '')
when Symbol then desc.to_s
when Module
raise ArgumentError, "Anonymous modules have no name to be referenced by" if desc.name.blank?
desc.name
desc.name.presence ||
raise(ArgumentError, "Anonymous modules have no name to be referenced by")
else raise TypeError, "Not a valid constant descriptor: #{desc.inspect}"
end
end
@ -607,16 +555,13 @@ module ActiveSupport #:nodoc:
def remove_constant(const) #:nodoc:
return false unless qualified_const_defined? const
const = $1 if /\A::(.*)\Z/ =~ const.to_s
names = const.to_s.split('::')
if names.size == 1 # It's under Object
parent = Object
else
parent = Inflector.constantize(names[0..-2] * '::')
end
# Normalize ::Foo, Foo, Object::Foo, and ::Object::Foo to Object::Foo
names = const.to_s.sub(/^::(Object)?/, 'Object::').split("::")
to_remove = names.pop
parent = Inflector.constantize(names * '::')
log "removing constant #{const}"
parent.instance_eval { remove_const names.last }
parent.instance_eval { remove_const to_remove }
return true
end

View File

@ -291,7 +291,7 @@ class DependenciesTest < Test::Unit::TestCase
assert ActiveSupport::Dependencies.qualified_const_defined?("::Test::Unit::TestCase")
end
def test_qualified_const_defined_should_not_call_method_missing
def test_qualified_const_defined_should_not_call_const_missing
ModuleWithMissing.missing_count = 0
assert ! ActiveSupport::Dependencies.qualified_const_defined?("ModuleWithMissing::A")
assert_equal 0, ModuleWithMissing.missing_count
@ -299,6 +299,10 @@ class DependenciesTest < Test::Unit::TestCase
assert_equal 0, ModuleWithMissing.missing_count
end
def test_qualified_const_defined_explodes_with_invalid_const_name
assert_raises(NameError) { ActiveSupport::Dependencies.qualified_const_defined?("invalid") }
end
def test_autoloaded?
with_autoloading_fixtures do
assert ! ActiveSupport::Dependencies.autoloaded?("ModuleFolder")
@ -333,7 +337,6 @@ class DependenciesTest < Test::Unit::TestCase
assert_equal "A", ActiveSupport::Dependencies.qualified_name_for(:Object, :A)
assert_equal "A", ActiveSupport::Dependencies.qualified_name_for("Object", :A)
assert_equal "A", ActiveSupport::Dependencies.qualified_name_for("::Object", :A)
assert_equal "A", ActiveSupport::Dependencies.qualified_name_for("::Kernel", :A)
assert_equal "ActiveSupport::Dependencies::A", ActiveSupport::Dependencies.qualified_name_for(:'ActiveSupport::Dependencies', :A)
assert_equal "ActiveSupport::Dependencies::A", ActiveSupport::Dependencies.qualified_name_for(ActiveSupport::Dependencies, :A)
@ -460,14 +463,6 @@ class DependenciesTest < Test::Unit::TestCase
end
end
def test_const_missing_on_kernel_should_fallback_to_object
with_autoloading_fixtures do
kls = Kernel::E
assert_equal "E", kls.name
assert_equal kls.object_id, Kernel::E.object_id
end
end
def test_preexisting_constants_are_not_marked_as_autoloaded
with_autoloading_fixtures do
require_dependency 'e'
@ -711,7 +706,7 @@ class DependenciesTest < Test::Unit::TestCase
def test_autoload_doesnt_shadow_name_error
with_autoloading_fixtures do
Object.send(:remove_const, :RaisesNameError) if defined?(::RaisesNameError)
2.times do
2.times do |i|
begin
::RaisesNameError::FooBarBaz.object_id
flunk 'should have raised NameError when autoloaded file referenced FooBarBaz'