X-Git-Url: https://git.njae.me.uk/?a=blobdiff_plain;f=vendor%2Frails%2Factivesupport%2Flib%2Factive_support%2Fdependencies.rb;fp=vendor%2Frails%2Factivesupport%2Flib%2Factive_support%2Fdependencies.rb;h=e7df2bdbeee9699c8a8e70b4e96fe8dcdfbd4316;hb=d115f2e23823271635bad69229a42cd8ac68debe;hp=0000000000000000000000000000000000000000;hpb=37cb670bf3ddde90b214e591f100ed4446469484;p=depot.git

diff --git a/vendor/rails/activesupport/lib/active_support/dependencies.rb b/vendor/rails/activesupport/lib/active_support/dependencies.rb
new file mode 100644
index 0000000..e7df2bd
--- /dev/null
+++ b/vendor/rails/activesupport/lib/active_support/dependencies.rb
@@ -0,0 +1,621 @@
+module ActiveSupport #:nodoc:
+  module Dependencies #:nodoc:
+    extend self
+
+    # Should we turn on Ruby warnings on the first load of dependent files?
+    mattr_accessor :warnings_on_first_load
+    self.warnings_on_first_load = false
+
+    # All files ever loaded.
+    mattr_accessor :history
+    self.history = Set.new
+
+    # All files currently loaded.
+    mattr_accessor :loaded
+    self.loaded = Set.new
+
+    # Should we load files or require them?
+    mattr_accessor :mechanism
+    self.mechanism = :load
+
+    # The set of directories from which we may automatically load files. Files
+    # under these directories will be reloaded on each request in development mode,
+    # unless the directory also appears in load_once_paths.
+    mattr_accessor :load_paths
+    self.load_paths = []
+
+    # The set of directories from which automatically loaded constants are loaded
+    # only once. All directories in this set must also be present in +load_paths+.
+    mattr_accessor :load_once_paths
+    self.load_once_paths = []
+
+    # An array of qualified constant names that have been loaded. Adding a name to
+    # this array will cause it to be unloaded the next time Dependencies are cleared.
+    mattr_accessor :autoloaded_constants
+    self.autoloaded_constants = []
+
+    # An array of constant names that need to be unloaded on every request. Used
+    # to allow arbitrary constants to be marked for unloading.
+    mattr_accessor :explicitly_unloadable_constants
+    self.explicitly_unloadable_constants = []
+
+    # The logger is used for generating information on the action run-time (including benchmarking) if available.
+    # Can be set to nil for no logging. Compatible with both Ruby's own Logger and Log4r loggers.
+    mattr_accessor :logger
+
+    # Set to true to enable logging of const_missing and file loads
+    mattr_accessor :log_activity
+    self.log_activity = false
+
+    # An internal stack used to record which constants are loaded by any block.
+    mattr_accessor :constant_watch_stack
+    self.constant_watch_stack = []
+
+    # Module includes this module
+    module ModuleConstMissing #:nodoc:
+      def self.included(base) #:nodoc:
+        base.class_eval do
+          unless defined? const_missing_without_dependencies
+            alias_method_chain :const_missing, :dependencies
+          end
+        end
+      end
+
+      def self.excluded(base) #:nodoc:
+        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
+        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
+      end
+
+      def unloadable(const_desc = self)
+        super(const_desc)
+      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
+      end
+
+      def require_or_load(file_name)
+        Dependencies.require_or_load(file_name)
+      end
+
+      def require_dependency(file_name)
+        Dependencies.depend_on(file_name)
+      end
+
+      def require_association(file_name)
+        Dependencies.associate_with(file_name)
+      end
+
+      def load_with_new_constant_marking(file, *extras) #:nodoc:
+        if Dependencies.load?
+          Dependencies.new_constants_in(Object) { load_without_new_constant_marking(file, *extras) }
+        else
+          load_without_new_constant_marking(file, *extras)
+        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
+      end
+
+      # Mark the given constant as unloadable. Unloadable constants are removed each
+      # time dependencies are cleared.
+      #
+      # Note that marking a constant for unloading need only be done once. Setup
+      # or init scripts may list each unloadable constant that may need unloading;
+      # each constant will be removed for every subsequent clear, as opposed to for
+      # the first clear.
+      #
+      # The provided constant descriptor may be a (non-anonymous) module or class,
+      # or a qualified constant name as a string or symbol.
+      #
+      # Returns true if the constant was not previously marked for unloading, false
+      # otherwise.
+      def unloadable(const_desc)
+        Dependencies.mark_for_unload const_desc
+      end
+    end
+
+    # Exception file-blaming
+    module Blamable #:nodoc:
+      def blame_file!(file)
+        (@blamed_files ||= []).unshift file
+      end
+
+      def blamed_files
+        @blamed_files ||= []
+      end
+
+      def describe_blame
+        return nil if blamed_files.empty?
+        "This error occurred while loading the following files:\n   #{blamed_files.join "\n   "}"
+      end
+
+      def copy_blame!(exc)
+        @blamed_files = exc.blamed_files.clone
+        self
+      end
+    end
+
+    def hook!
+      Object.instance_eval { include Loadable }
+      Module.instance_eval { include ModuleConstMissing }
+      Class.instance_eval { include ClassConstMissing }
+      Exception.instance_eval { include Blamable }
+      true
+    end
+
+    def unhook!
+      ModuleConstMissing.excluded(Module)
+      Loadable.excluded(Object)
+      true
+    end
+
+    def load?
+      mechanism == :load
+    end
+
+    def depend_on(file_name, swallow_load_errors = false)
+      path = search_for_file(file_name)
+      require_or_load(path || file_name)
+    rescue LoadError
+      raise unless swallow_load_errors
+    end
+
+    def associate_with(file_name)
+      depend_on(file_name, true)
+    end
+
+    def clear
+      log_call
+      loaded.clear
+      remove_unloadable_constants!
+    end
+
+    def require_or_load(file_name, const_path = nil)
+      log_call file_name, const_path
+      file_name = $1 if file_name =~ /^(.*)\.rb$/
+      expanded = File.expand_path(file_name)
+      return if loaded.include?(expanded)
+
+      # Record that we've seen this file *before* loading it to avoid an
+      # infinite loop with mutual dependencies.
+      loaded << expanded
+
+      begin
+        if load?
+          log "loading #{file_name}"
+
+          # Enable warnings iff this file has not been loaded before and
+          # warnings_on_first_load is set.
+          load_args = ["#{file_name}.rb"]
+          load_args << const_path unless const_path.nil?
+
+          if !warnings_on_first_load or history.include?(expanded)
+            result = load_file(*load_args)
+          else
+            enable_warnings { result = load_file(*load_args) }
+          end
+        else
+          log "requiring #{file_name}"
+          result = require file_name
+        end
+      rescue Exception
+        loaded.delete expanded
+        raise
+      end
+
+      # Record history *after* loading so first load gets warnings.
+      history << expanded
+      return result
+    end
+
+    # 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.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)
+        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)
+        mod.const_defined?(const)
+      end
+    else
+      def uninherited_const_defined?(mod, const) #:nodoc:
+        mod.const_defined?(const, false)
+      end
+    end
+
+    # 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)
+
+      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.camelize,
+          # Special case: application.rb might define ApplicationControlller.
+          ('ApplicationController' if nesting == 'application')
+        ]
+      end.flatten.compact.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.ends_with? '.rb'
+      load_paths.each do |root|
+        path = File.join(root, path_suffix)
+        return path if File.file? path
+      end
+      nil # Gee, I sure wish we had first_match ;-)
+    end
+
+    # Does the provided path_suffix correspond to an autoloadable module?
+    # Instead of returning a boolean, the autoload base for this module is returned.
+    def autoloadable_module?(path_suffix)
+      load_paths.each do |load_path|
+        return load_path if File.directory? File.join(load_path, path_suffix)
+      end
+      nil
+    end
+
+    def load_once_path?(path)
+      load_once_paths.any? { |base| path.starts_with? base }
+    end
+
+    # Attempt to autoload the provided module name by searching for a directory
+    # matching the expect path suffix. If found, the module is created and assigned
+    # to +into+'s constants with the name +const_name+. Provided that the directory
+    # was loaded from a reloadable base path, it is added to the set of constants
+    # that are to be unloaded.
+    def autoload_module!(into, const_name, qualified_name, path_suffix)
+      return nil unless base_path = autoloadable_module?(path_suffix)
+      mod = Module.new
+      into.const_set const_name, mod
+      autoloaded_constants << qualified_name unless load_once_paths.include?(base_path)
+      return mod
+    end
+
+    # Load the file at the provided path. +const_paths+ is a set of qualified
+    # constant names. When loading the file, Dependencies will watch for the
+    # addition of these constants. Each that is defined will be marked as
+    # autoloaded, and will be removed when Dependencies.clear is next called.
+    #
+    # If the second parameter is left off, then Dependencies will construct a set
+    # of names that the file at +path+ may define. See
+    # +loadable_constants_for_path+ for more details.
+    def load_file(path, const_paths = loadable_constants_for_path(path))
+      log_call path, const_paths
+      const_paths = [const_paths].compact unless const_paths.is_a? Array
+      parent_paths = const_paths.collect { |const_path| /(.*)::[^:]+\Z/ =~ const_path ? $1 : :Object }
+
+      result = nil
+      newly_defined_paths = new_constants_in(*parent_paths) do
+        result = load_without_new_constant_marking path
+      end
+
+      autoloaded_constants.concat newly_defined_paths unless load_once_path?(path)
+      autoloaded_constants.uniq!
+      log "loading #{path} defined #{newly_defined_paths * ', '}" unless newly_defined_paths.empty?
+      return result
+    end
+
+    # 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}"
+    end
+
+    # Load the constant named +const_name+ which is missing from +from_mod+. If
+    # it is not possible to load the constant into from_mod, try its parent module
+    # 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) && from_mod.name.constantize.object_id == from_mod.object_id
+        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)
+
+      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)
+        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) }
+        # 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
+        # return constants from from_mod's parents.
+        begin
+          return parent.const_missing(const_name)
+        rescue NameError => e
+          raise unless e.missing_name? qualified_name_for(parent, const_name)
+          raise name_error
+        end
+      else
+        raise name_error
+      end
+    end
+
+    # Remove the constants that have been autoloaded, and those that have been
+    # marked for unloading.
+    def remove_unloadable_constants!
+      autoloaded_constants.each { |const| remove_constant const }
+      autoloaded_constants.clear
+      explicitly_unloadable_constants.each { |const| remove_constant const }
+    end
+
+    # Determine if the given constant has been automatically loaded.
+    def autoloaded?(desc)
+      # No name => anonymous module.
+      return false if desc.is_a?(Module) && desc.name.blank?
+      name = to_constant_name desc
+      return false unless qualified_const_defined? name
+      return autoloaded_constants.include?(name)
+    end
+
+    # Will the provided constant descriptor be unloaded?
+    def will_unload?(const_desc)
+      autoloaded?(const_desc) ||
+        explicitly_unloadable_constants.include?(to_constant_name(const_desc))
+    end
+
+    # Mark the provided constant name for unloading. This constant will be
+    # unloaded on each request, not just the next one.
+    def mark_for_unload(const_desc)
+      name = to_constant_name const_desc
+      if explicitly_unloadable_constants.include? name
+        return false
+      else
+        explicitly_unloadable_constants << name
+        return true
+      end
+    end
+
+    # Run the provided block and detect the new constants that were loaded during
+    # its execution. Constants may only be regarded as 'new' once -- so if the
+    # block calls +new_constants_in+ again, then the constants defined within the
+    # inner call will not be reported in this one.
+    #
+    # If the provided block does not run to completion, and instead raises an
+    # exception, any new constants are regarded as being only partially defined
+    # 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)
+            mod_name.constantize.local_constant_names
+          else
+            []
+          end
+        else
+          raise Argument, "#{desc.inspect} does not describe a module!"
+        end
+
+        [mod_name, initial_constants]
+      end
+
+      constant_watch_stack.concat watch_frames
+
+      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 = mod_name.constantize
+          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.each do |frame_name, constants|
+            constants.concat new_constants if frame_name == mod_name
+          end
+
+          new_constants.collect do |suffix|
+            mod_name == "Object" ? suffix : "#{mod_name}::#{suffix}"
+          end
+        end.flatten
+
+        log "New constants: #{new_constants * ', '}"
+
+        if aborting
+          log "Error during loading, removing partially loaded constants "
+          new_constants.each { |name| remove_constant name }
+          new_constants.clear
+        end
+      end
+
+      return new_constants
+    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.delete_if do |watch_frame|
+          frame_ids.include? watch_frame.object_id
+        end
+      end
+    end
+
+    class LoadingModule #:nodoc:
+      # Old style environment.rb referenced this method directly.  Please note, it doesn't
+      # actually *do* anything any more.
+      def self.root(*args)
+        if defined?(RAILS_DEFAULT_LOGGER)
+          RAILS_DEFAULT_LOGGER.warn "Your environment.rb uses the old syntax, it may not continue to work in future releases."
+          RAILS_DEFAULT_LOGGER.warn "For upgrade instructions please see: http://manuals.rubyonrails.com/read/book/19"
+        end
+      end
+    end
+
+    # Convert the provided const desc to a qualified constant name (as a string).
+    # 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 Symbol then desc.to_s
+        when Module
+          raise ArgumentError, "Anonymous modules have no name to be referenced by" if desc.name.blank?
+          desc.name
+        else raise TypeError, "Not a valid constant descriptor: #{desc.inspect}"
+      end
+    end
+
+    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 = (names[0..-2] * '::').constantize
+      end
+
+      log "removing constant #{const}"
+      parent.instance_eval { remove_const names.last }
+      return true
+    end
+
+    protected
+      def log_call(*args)
+        if logger && log_activity
+          arg_str = args.collect { |arg| arg.inspect } * ', '
+          /in `([a-z_\?\!]+)'/ =~ caller(1).first
+          selector = $1 || '<unknown>'
+          log "called #{selector}(#{arg_str})"
+        end
+      end
+
+      def log(msg)
+        if logger && log_activity
+          logger.debug "Dependencies: #{msg}"
+        end
+      end
+  end
+end
+
+ActiveSupport::Dependencies.hook!