lib/ostruct.rb in ostruct-0.1.0 vs lib/ostruct.rb in ostruct-0.3.0
- old
+ new
@@ -34,13 +34,14 @@
# # => #<OpenStruct country="Australia", capital="Canberra">
#
# Hash keys with spaces or characters that could normally not be used for
# method calls (e.g. <code>()[]*</code>) will not be immediately available
# on the OpenStruct object as a method for retrieval or assignment, but can
-# still be reached through the Object#send method.
+# still be reached through the Object#send method or using [].
#
# measurements = OpenStruct.new("length (in inches)" => 24)
+# measurements[:"length (in inches)"] # => 24
# measurements.send("length (in inches)") # => 24
#
# message = OpenStruct.new(:queued? => true)
# message.queued? # => true
# message.send("queued?=", false)
@@ -59,22 +60,56 @@
#
# first_pet.delete_field(:owner)
# first_pet # => #<OpenStruct name="Rowdy">
# first_pet == second_pet # => true
#
+# Ractor compatibility: A frozen OpenStruct with shareable values is itself shareable.
#
-# == Implementation
+# == Caveats
#
# An OpenStruct utilizes Ruby's method lookup structure to find and define the
# necessary methods for properties. This is accomplished through the methods
# method_missing and define_singleton_method.
#
# This should be a consideration if there is a concern about the performance of
# the objects that are created, as there is much more overhead in the setting
# of these properties compared to using a Hash or a Struct.
+# Creating an open struct from a small Hash and accessing a few of the
+# entries can be 200 times slower than accessing the hash directly.
#
+# This is a potential security issue; building OpenStruct from untrusted user data
+# (e.g. JSON web request) may be susceptible to a "symbol denial of service" attack
+# since the keys create methods and names of methods are never garbage collected.
+#
+# This may also be the source of incompatibilities between Ruby versions:
+#
+# o = OpenStruct.new
+# o.then # => nil in Ruby < 2.6, enumerator for Ruby >= 2.6
+#
+# Builtin methods may be overwritten this way, which may be a source of bugs
+# or security issues:
+#
+# o = OpenStruct.new
+# o.methods # => [:to_h, :marshal_load, :marshal_dump, :each_pair, ...
+# o.methods = [:foo, :bar]
+# o.methods # => [:foo, :bar]
+#
+# To help remedy clashes, OpenStruct uses only protected/private methods ending with `!`
+# and defines aliases for builtin public methods by adding a `!`:
+#
+# o = OpenStruct.new(make: 'Bentley', class: :luxury)
+# o.class # => :luxury
+# o.class! # => OpenStruct
+#
+# It is recommended (but not enforced) to not use fields ending in `!`;
+# Note that a subclass' methods may not be overwritten, nor can OpenStruct's own methods
+# ending with `!`.
+#
+# For all these reasons, consider not using OpenStruct at all.
+#
class OpenStruct
+ VERSION = "0.3.0"
#
# Creates a new OpenStruct object. By default, the resulting OpenStruct
# object will have no attributes.
#
@@ -87,35 +122,68 @@
# data = OpenStruct.new(hash)
#
# data # => #<OpenStruct country="Australia", capital="Canberra">
#
def initialize(hash=nil)
- @table = {}
if hash
- hash.each_pair do |k, v|
- k = k.to_sym
- @table[k] = v
- end
+ update_to_values!(hash)
+ else
+ @table = {}
end
end
# Duplicates an OpenStruct object's Hash table.
- def initialize_copy(orig) # :nodoc:
+ private def initialize_clone(orig) # :nodoc:
+ super # clones the singleton class for us
+ @table = @table.dup unless @table.frozen?
+ end
+
+ private def initialize_dup(orig) # :nodoc:
super
- @table = @table.dup
+ update_to_values!(@table)
end
+ private def update_to_values!(hash) # :nodoc:
+ @table = {}
+ hash.each_pair do |k, v|
+ set_ostruct_member_value!(k, v)
+ end
+ end
+
#
+ # call-seq:
+ # ostruct.to_h -> hash
+ # ostruct.to_h {|name, value| block } -> hash
+ #
# Converts the OpenStruct to a hash with keys representing
# each attribute (as symbols) and their corresponding values.
#
+ # If a block is given, the results of the block on each pair of
+ # the receiver will be used as pairs.
+ #
# require "ostruct"
# data = OpenStruct.new("country" => "Australia", :capital => "Canberra")
# data.to_h # => {:country => "Australia", :capital => "Canberra" }
+ # data.to_h {|name, value| [name.to_s, value.upcase] }
+ # # => {"country" => "AUSTRALIA", "capital" => "CANBERRA" }
#
- def to_h
- @table.dup
+ if {test: :to_h}.to_h{ [:works, true] }[:works] # RUBY_VERSION < 2.6 compatibility
+ def to_h(&block)
+ if block
+ @table.to_h(&block)
+ else
+ @table.dup
+ end
+ end
+ else
+ def to_h(&block)
+ if block
+ @table.map(&block).to_h
+ else
+ @table.dup
+ end
+ end
end
#
# :call-seq:
# ostruct.each_pair {|name, value| block } -> ostruct
@@ -135,96 +203,73 @@
end
#
# Provides marshalling support for use by the Marshal library.
#
- def marshal_dump
+ def marshal_dump # :nodoc:
@table
end
#
# Provides marshalling support for use by the Marshal library.
#
- def marshal_load(x)
+ def marshal_load(x) # :nodoc:
+ x.each_key{|key| new_ostruct_member!(key)}
@table = x
end
#
- # Used internally to check if the OpenStruct is able to be
- # modified before granting access to the internal Hash table to be modified.
- #
- def modifiable? # :nodoc:
- begin
- @modifiable = true
- rescue
- exception_class = defined?(FrozenError) ? FrozenError : RuntimeError
- raise exception_class, "can't modify frozen #{self.class}", caller(3)
- end
- @table
- end
- private :modifiable?
-
- # ::Kernel.warn("do not use OpenStruct#modifiable", uplevel: 1)
- alias modifiable modifiable? # :nodoc:
- protected :modifiable
-
- #
# Used internally to defined properties on the
# OpenStruct. It does this by using the metaprogramming function
# define_singleton_method for both the getter method and the setter method.
#
def new_ostruct_member!(name) # :nodoc:
- name = name.to_sym
- unless singleton_class.method_defined?(name)
- define_singleton_method(name) { @table[name] }
- define_singleton_method("#{name}=") {|x| modifiable?[name] = x}
+ unless @table.key?(name) || is_method_protected!(name)
+ define_singleton_method!(name) { @table[name] }
+ define_singleton_method!("#{name}=") {|x| @table[name] = x}
end
- name
end
private :new_ostruct_member!
- # ::Kernel.warn("do not use OpenStruct#new_ostruct_member", uplevel: 1)
- alias new_ostruct_member new_ostruct_member! # :nodoc:
- protected :new_ostruct_member
+ private def is_method_protected!(name) # :nodoc:
+ if !respond_to?(name, true)
+ false
+ elsif name.match?(/!$/)
+ true
+ else
+ method!(name).owner < OpenStruct
+ end
+ end
def freeze
- @table.each_key {|key| new_ostruct_member!(key)}
+ @table.freeze
super
end
- def respond_to_missing?(mid, include_private = false) # :nodoc:
- mname = mid.to_s.chomp("=").to_sym
- @table&.key?(mname) || super
- end
-
- def method_missing(mid, *args) # :nodoc:
+ private def method_missing(mid, *args) # :nodoc:
len = args.length
if mname = mid[/.*(?==\z)/m]
if len != 1
- raise ArgumentError, "wrong number of arguments (#{len} for 1)", caller(1)
+ raise! ArgumentError, "wrong number of arguments (given #{len}, expected 1)", caller(1)
end
- modifiable?[new_ostruct_member!(mname)] = args[0]
- elsif len == 0 # and /\A[a-z_]\w*\z/ =~ mid #
- if @table.key?(mid)
- new_ostruct_member!(mid) unless frozen?
- @table[mid]
- end
+ set_ostruct_member_value!(mname, args[0])
+ elsif len == 0
else
begin
super
rescue NoMethodError => err
err.backtrace.shift
- raise
+ raise!
end
end
end
#
# :call-seq:
# ostruct[name] -> object
#
- # Returns the value of an attribute.
+ # Returns the value of an attribute, or `nil` if there is no such attribute.
#
# require "ostruct"
# person = OpenStruct.new("name" => "John Smith", "age" => 70)
# person[:age] # => 70, same as person.age
#
@@ -242,38 +287,36 @@
# person = OpenStruct.new("name" => "John Smith", "age" => 70)
# person[:age] = 42 # equivalent to person.age = 42
# person.age # => 42
#
def []=(name, value)
- modifiable?[new_ostruct_member!(name)] = value
+ name = name.to_sym
+ new_ostruct_member!(name)
+ @table[name] = value
end
+ alias_method :set_ostruct_member_value!, :[]=
+ private :set_ostruct_member_value!
- #
# :call-seq:
- # ostruct.dig(name, ...) -> object
+ # ostruct.dig(name, *identifiers) -> object
#
- # Extracts the nested value specified by the sequence of +name+
- # objects by calling +dig+ at each step, returning +nil+ if any
- # intermediate step is +nil+.
+ # Finds and returns the object in nested objects
+ # that is specified by +name+ and +identifiers+.
+ # The nested objects may be instances of various classes.
+ # See {Dig Methods}[rdoc-ref:doc/dig_methods.rdoc].
#
+ # Examples:
# require "ostruct"
# address = OpenStruct.new("city" => "Anytown NC", "zip" => 12345)
# person = OpenStruct.new("name" => "John Smith", "address" => address)
- #
- # person.dig(:address, "zip") # => 12345
- # person.dig(:business_address, "zip") # => nil
- #
- # data = OpenStruct.new(:array => [1, [2, 3]])
- #
- # data.dig(:array, 1, 0) # => 2
- # data.dig(:array, 0, 0) # TypeError: Integer does not have #dig method
- #
+ # person.dig(:address, "zip") # => 12345
+ # person.dig(:business_address, "zip") # => nil
def dig(name, *names)
begin
name = name.to_sym
rescue NoMethodError
- raise TypeError, "#{name} is not a symbol nor a string"
+ raise! TypeError, "#{name} is not a symbol nor a string"
end
@table.dig(name, *names)
end
#
@@ -282,11 +325,11 @@
#
# require "ostruct"
#
# person = OpenStruct.new(name: "John", age: 70, pension: 300)
#
- # person.delete_field("age") # => 70
+ # person.delete_field!("age") # => 70
# person # => #<OpenStruct name="John", pension=300>
#
# Setting the value to +nil+ will not remove the attribute:
#
# person.pension = nil
@@ -297,11 +340,11 @@
begin
singleton_class.remove_method(sym, "#{sym}=")
rescue NameError
end
@table.delete(sym) do
- raise NameError.new("no field `#{sym}' in #{self}", sym)
+ raise! NameError.new("no field `#{sym}' in #{self}", sym)
end
end
InspectKey = :__inspect_key__ # :nodoc:
@@ -320,17 +363,17 @@
end.join(',')
ensure
ids.pop
end
end
- ['#<', self.class, detail, '>'].join
+ ['#<', self.class!, detail, '>'].join
end
alias :to_s :inspect
attr_reader :table # :nodoc:
- protected :table
alias table! table
+ protected :table!
#
# Compares this object and +other+ for equality. An OpenStruct is equal to
# +other+ when +other+ is an OpenStruct and the two objects' Hash tables are
# equal.
@@ -357,13 +400,45 @@
return false unless other.kind_of?(OpenStruct)
@table.eql?(other.table!)
end
# Computes a hash code for this OpenStruct.
- # Two OpenStruct objects with the same content will have the same hash code
- # (and will compare using #eql?).
- #
- # See also Object#hash.
- def hash
+ def hash # :nodoc:
@table.hash
end
+
+ #
+ # Provides marshalling support for use by the YAML library.
+ #
+ def encode_with(coder) # :nodoc:
+ @table.each_pair do |key, value|
+ coder[key.to_s] = value
+ end
+ if @table.size == 1 && @table.key?(:table) # support for legacy format
+ # in the very unlikely case of a single entry called 'table'
+ coder['legacy_support!'] = true # add a bogus second entry
+ end
+ end
+
+ #
+ # Provides marshalling support for use by the YAML library.
+ #
+ def init_with(coder) # :nodoc:
+ h = coder.map
+ if h.size == 1 # support for legacy format
+ key, val = h.first
+ if key == 'table'
+ h = val
+ end
+ end
+ update_to_values!(h)
+ end
+
+ # Make all public methods (builtin or our own) accessible with `!`:
+ instance_methods.each do |method|
+ new_name = "#{method}!"
+ alias_method new_name, method
+ end
+ # Other builtin private methods we use:
+ alias_method :raise!, :raise
+ private :raise!
end