diff --git a/lib/couchrest/support/class.rb b/lib/couchrest/support/class.rb index 3b5f370..1862c31 100644 --- a/lib/couchrest/support/class.rb +++ b/lib/couchrest/support/class.rb @@ -25,151 +25,167 @@ # example, an array without those additions being shared with either their # parent, siblings, or children, which is unlike the regular class-level # attributes that are shared across the entire hierarchy. -class Class - # Defines class-level and instance-level attribute reader. - # - # @param *syms Array of attributes to define reader for. - # @return List of attributes that were made into cattr_readers - # - # @api public - # - # @todo Is this inconsistent in that it does not allow you to prevent - # an instance_reader via :instance_reader => false - def cattr_reader(*syms) - syms.flatten.each do |sym| - next if sym.is_a?(Hash) - class_eval(<<-RUBY, __FILE__, __LINE__ + 1) -unless defined? @@#{sym} -@@#{sym} = nil -end - -def self.#{sym} -@@#{sym} -end - -def #{sym} -@@#{sym} -end -RUBY +module CouchRest + module ClassExtension + def self.included(base) + if CouchRest::ClassExtension::InstanceMethods.instance_methods.all? {|m| base.respond_to?(m)} + # do nothing + elsif CouchRest::ClassExtension::InstanceMethods.instance_methods.any? {|m| base.respond_to?(m)} + raise RuntimeError, "Conflicting extentions to Class, work it out" + else + base.send(:include, CouchRest::ClassExtension::InstanceMethods) + end + end + + module InstanceMethods + # Defines class-level and instance-level attribute reader. + # + # @param *syms Array of attributes to define reader for. + # @return List of attributes that were made into cattr_readers + # + # @api public + # + # @todo Is this inconsistent in that it does not allow you to prevent + # an instance_reader via :instance_reader => false + def cattr_reader(*syms) + syms.flatten.each do |sym| + next if sym.is_a?(Hash) + class_eval(<<-RUBY, __FILE__, __LINE__ + 1) + unless defined? @@#{sym} + @@#{sym} = nil end - end - # Defines class-level (and optionally instance-level) attribute writer. - # - # @param Boolean}]> Array of attributes to define writer for. - # @option syms :instance_writer if true, instance-level attribute writer is defined. - # @return List of attributes that were made into cattr_writers - # - # @api public - def cattr_writer(*syms) - options = syms.last.is_a?(Hash) ? syms.pop : {} - syms.flatten.each do |sym| - class_eval(<<-RUBY, __FILE__, __LINE__ + 1) -unless defined? @@#{sym} -@@#{sym} = nil -end + def self.#{sym} + @@#{sym} + end -def self.#{sym}=(obj) -@@#{sym} = obj -end -RUBY + def #{sym} + @@#{sym} + end + RUBY + end + end - unless options[:instance_writer] == false - class_eval(<<-RUBY, __FILE__, __LINE__ + 1) -def #{sym}=(obj) -@@#{sym} = obj -end -RUBY + # Defines class-level (and optionally instance-level) attribute writer. + # + # @param Boolean}]> Array of attributes to define writer for. + # @option syms :instance_writer if true, instance-level attribute writer is defined. + # @return List of attributes that were made into cattr_writers + # + # @api public + def cattr_writer(*syms) + options = syms.last.is_a?(Hash) ? syms.pop : {} + syms.flatten.each do |sym| + class_eval(<<-RUBY, __FILE__, __LINE__ + 1) + unless defined? @@#{sym} + @@#{sym} = nil + end + + def self.#{sym}=(obj) + @@#{sym} = obj + end + RUBY + + unless options[:instance_writer] == false + class_eval(<<-RUBY, __FILE__, __LINE__ + 1) + def #{sym}=(obj) + @@#{sym} = obj + end + RUBY + end + end + end + + # Defines class-level (and optionally instance-level) attribute accessor. + # + # @param *syms Boolean}]> Array of attributes to define accessor for. + # @option syms :instance_writer if true, instance-level attribute writer is defined. + # @return List of attributes that were made into accessors + # + # @api public + def cattr_accessor(*syms) + cattr_reader(*syms) + cattr_writer(*syms) + end + + # Defines class-level inheritable attribute reader. Attributes are available to subclasses, + # each subclass has a copy of parent's attribute. + # + # @param *syms Array of attributes to define inheritable reader for. + # @return Array of attributes converted into inheritable_readers. + # + # @api public + # + # @todo Do we want to block instance_reader via :instance_reader => false + # @todo It would be preferable that we do something with a Hash passed in + # (error out or do the same as other methods above) instead of silently + # moving on). In particular, this makes the return value of this function + # less useful. + def class_inheritable_reader(*ivars) + instance_reader = ivars.pop[:reader] if ivars.last.is_a?(Hash) + + ivars.each do |ivar| + self.class_eval <<-RUBY, __FILE__, __LINE__ + 1 + def self.#{ivar} + return @#{ivar} if self.object_id == #{self.object_id} || defined?(@#{ivar}) + ivar = superclass.#{ivar} + return nil if ivar.nil? && !#{self}.instance_variable_defined?("@#{ivar}") + @#{ivar} = ivar && !ivar.is_a?(Module) && !ivar.is_a?(Numeric) && !ivar.is_a?(TrueClass) && !ivar.is_a?(FalseClass) && !ivar.is_a?(Symbol) ? ivar.dup : ivar + end + RUBY + unless instance_reader == false + self.class_eval <<-RUBY, __FILE__, __LINE__ + 1 + def #{ivar} + self.class.#{ivar} + end + RUBY + end + end + end + + # Defines class-level inheritable attribute writer. Attributes are available to subclasses, + # each subclass has a copy of parent's attribute. + # + # @param *syms Boolean}]> Array of attributes to + # define inheritable writer for. + # @option syms :instance_writer if true, instance-level inheritable attribute writer is defined. + # @return An Array of the attributes that were made into inheritable writers. + # + # @api public + # + # @todo We need a style for class_eval <<-HEREDOC. I'd like to make it + # class_eval(<<-RUBY, __FILE__, __LINE__), but we should codify it somewhere. + def class_inheritable_writer(*ivars) + instance_writer = ivars.pop[:instance_writer] if ivars.last.is_a?(Hash) + ivars.each do |ivar| + self.class_eval <<-RUBY, __FILE__, __LINE__ + 1 + def self.#{ivar}=(obj) + @#{ivar} = obj + end + RUBY + unless instance_writer == false + self.class_eval <<-RUBY, __FILE__, __LINE__ + 1 + def #{ivar}=(obj) self.class.#{ivar} = obj end + RUBY + end + end + end + + # Defines class-level inheritable attribute accessor. Attributes are available to subclasses, + # each subclass has a copy of parent's attribute. + # + # @param *syms Boolean}]> Array of attributes to + # define inheritable accessor for. + # @option syms :instance_writer if true, instance-level inheritable attribute writer is defined. + # @return An Array of attributes turned into inheritable accessors. + # + # @api public + def class_inheritable_accessor(*syms) + class_inheritable_reader(*syms) + class_inheritable_writer(*syms) end end end - - # Defines class-level (and optionally instance-level) attribute accessor. - # - # @param *syms Boolean}]> Array of attributes to define accessor for. - # @option syms :instance_writer if true, instance-level attribute writer is defined. - # @return List of attributes that were made into accessors - # - # @api public - def cattr_accessor(*syms) - cattr_reader(*syms) - cattr_writer(*syms) - end - - # Defines class-level inheritable attribute reader. Attributes are available to subclasses, - # each subclass has a copy of parent's attribute. - # - # @param *syms Array of attributes to define inheritable reader for. - # @return Array of attributes converted into inheritable_readers. - # - # @api public - # - # @todo Do we want to block instance_reader via :instance_reader => false - # @todo It would be preferable that we do something with a Hash passed in - # (error out or do the same as other methods above) instead of silently - # moving on). In particular, this makes the return value of this function - # less useful. - def class_inheritable_reader(*ivars) - instance_reader = ivars.pop[:reader] if ivars.last.is_a?(Hash) - - ivars.each do |ivar| - self.class_eval <<-RUBY, __FILE__, __LINE__ + 1 -def self.#{ivar} -return @#{ivar} if self.object_id == #{self.object_id} || defined?(@#{ivar}) -ivar = superclass.#{ivar} -return nil if ivar.nil? && !#{self}.instance_variable_defined?("@#{ivar}") -@#{ivar} = ivar && !ivar.is_a?(Module) && !ivar.is_a?(Numeric) && !ivar.is_a?(TrueClass) && !ivar.is_a?(FalseClass) && !ivar.is_a?(Symbol) ? ivar.dup : ivar end -RUBY - unless instance_reader == false - self.class_eval <<-RUBY, __FILE__, __LINE__ + 1 -def #{ivar} -self.class.#{ivar} -end -RUBY - end - end - end - - # Defines class-level inheritable attribute writer. Attributes are available to subclasses, - # each subclass has a copy of parent's attribute. - # - # @param *syms Boolean}]> Array of attributes to - # define inheritable writer for. - # @option syms :instance_writer if true, instance-level inheritable attribute writer is defined. - # @return An Array of the attributes that were made into inheritable writers. - # - # @api public - # - # @todo We need a style for class_eval <<-HEREDOC. I'd like to make it - # class_eval(<<-RUBY, __FILE__, __LINE__), but we should codify it somewhere. - def class_inheritable_writer(*ivars) - instance_writer = ivars.pop[:instance_writer] if ivars.last.is_a?(Hash) - ivars.each do |ivar| - self.class_eval <<-RUBY, __FILE__, __LINE__ + 1 -def self.#{ivar}=(obj) -@#{ivar} = obj -end -RUBY - unless instance_writer == false - self.class_eval <<-RUBY, __FILE__, __LINE__ + 1 -def #{ivar}=(obj) self.class.#{ivar} = obj end -RUBY - end - end - end - - # Defines class-level inheritable attribute accessor. Attributes are available to subclasses, - # each subclass has a copy of parent's attribute. - # - # @param *syms Boolean}]> Array of attributes to - # define inheritable accessor for. - # @option syms :instance_writer if true, instance-level inheritable attribute writer is defined. - # @return An Array of attributes turned into inheritable accessors. - # - # @api public - def class_inheritable_accessor(*syms) - class_inheritable_reader(*syms) - class_inheritable_writer(*syms) - end -end \ No newline at end of file + +Class.send(:include, CouchRest::ClassExtension) diff --git a/spec/couchrest/support/class_spec.rb b/spec/couchrest/support/class_spec.rb new file mode 100644 index 0000000..7805f42 --- /dev/null +++ b/spec/couchrest/support/class_spec.rb @@ -0,0 +1,59 @@ +require File.join(File.dirname(__FILE__), '..', '..', 'spec_helper') +require File.join(File.dirname(__FILE__), '..', '..', '..', 'lib', 'couchrest', 'support', 'class') + +describe CouchRest::ClassExtension do + + before :all do + class FullyDefinedClassExtensions + def self.respond_to?(method) + if CouchRest::ClassExtension::InstanceMethods.instance_methods.include?(method) + true + else + super + end + end + end + + class PartDefinedClassExtensions + def self.respond_to?(method) + methods = CouchRest::ClassExtension::InstanceMethods.instance_methods + methods.delete('cattr_reader') + + if methods.include?(method) + false + else + super + end + end + end + + class NoClassExtensions + def self.respond_to?(method) + if CouchRest::ClassExtension::InstanceMethods.instance_methods.include?(method) + false + else + super + end + end + end + + + end + + it "should not include InstanceMethods if the class extensions are already defined" do + FullyDefinedClassExtensions.send(:include, CouchRest::ClassExtension) + FullyDefinedClassExtensions.ancestors.should_not include(CouchRest::ClassExtension::InstanceMethods) + end + + it "should raise RuntimeError if the class extensions are only partially defined" do + lambda { + PartDefinedClassExtensions.send(:include, CouchRest::ClassExtension) + }.should raise_error(RuntimeError) + end + + it "should include class extensions if they are not already defined" do + NoClassExtensions.send(:include, CouchRest::ClassExtension) + NoClassExtensions.ancestors.should include(CouchRest::ClassExtension::InstanceMethods) + end + +end \ No newline at end of file