stdlib/pp.rb
# frozen_string_literal: true
# backtick_javascript: true
# Opal: load stdlib/thread.rb
require 'thread'
require 'stringio'
require 'prettyprint'
##
# A pretty-printer for Ruby objects.
#
##
# == What PP Does
#
# Standard output by #p returns this:
# #<PP:0x81fedf0 @genspace=#<Proc:0x81feda0>, @group_queue=#<PrettyPrint::GroupQueue:0x81fed3c @queue=[[#<PrettyPrint::Group:0x81fed78 @breakables=[], @depth=0, @break=false>], []]>, @buffer=[], @newline="\n", @group_stack=[#<PrettyPrint::Group:0x81fed78 @breakables=[], @depth=0, @break=false>], @buffer_width=0, @indent=0, @maxwidth=79, @output_width=2, @output=#<IO:0x8114ee4>>
#
# Pretty-printed output returns this:
# #<PP:0x81fedf0
# @buffer=[],
# @buffer_width=0,
# @genspace=#<Proc:0x81feda0>,
# @group_queue=
# #<PrettyPrint::GroupQueue:0x81fed3c
# @queue=
# [[#<PrettyPrint::Group:0x81fed78 @break=false, @breakables=[], @depth=0>],
# []]>,
# @group_stack=
# [#<PrettyPrint::Group:0x81fed78 @break=false, @breakables=[], @depth=0>],
# @indent=0,
# @maxwidth=79,
# @newline="\n",
# @output=#<IO:0x8114ee4>,
# @output_width=2>
#
##
# == Usage
#
# pp(obj) #=> obj
# pp obj #=> obj
# pp(obj1, obj2, ...) #=> [obj1, obj2, ...]
# pp() #=> nil
#
# Output <tt>obj(s)</tt> to <tt>$></tt> in pretty printed format.
#
# It returns <tt>obj(s)</tt>.
#
##
# == Output Customization
#
# To define a customized pretty printing function for your classes,
# redefine method <code>#pretty_print(pp)</code> in the class.
#
# <code>#pretty_print</code> takes the +pp+ argument, which is an instance of the PP class.
# The method uses #text, #breakable, #nest, #group and #pp to print the
# object.
#
##
# == Pretty-Print JSON
#
# To pretty-print JSON refer to JSON#pretty_generate.
#
##
# == Author
# Tanaka Akira <akr@fsij.org>
class PP < PrettyPrint
# Outputs +obj+ to +out+ in pretty printed format of
# +width+ columns in width.
#
# If +out+ is omitted, <code>$></code> is assumed.
# If +width+ is omitted, 79 is assumed.
#
# PP.pp returns +out+.
def PP.pp(obj, out=$stdout, width=79) # Opal: replace $> with $stdout
q = PP.new(out, width)
q.guard_inspect_key {q.pp obj}
q.flush
#$pp = q
out << "\n"
end
# Outputs +obj+ to +out+ like PP.pp but with no indent and
# newline.
#
# PP.singleline_pp returns +out+.
def PP.singleline_pp(obj, out=$stdout) # Opal: replace $> with $stdout
q = SingleLine.new(out)
q.guard_inspect_key {q.pp obj}
q.flush
out
end
# :stopdoc:
def PP.mcall(obj, mod, meth, *args, &block)
mod.instance_method(meth).bind_call(obj, *args, &block)
end
# :startdoc:
@sharing_detection = false
class << self
# Returns the sharing detection flag as a boolean value.
# It is false by default.
attr_accessor :sharing_detection
end
module PPMethods
# Yields to a block
# and preserves the previous set of objects being printed.
def guard_inspect_key
if Thread.current[:__recursive_key__] == nil
Thread.current[:__recursive_key__] = {}.compare_by_identity
end
if Thread.current[:__recursive_key__][:inspect] == nil
Thread.current[:__recursive_key__][:inspect] = {}.compare_by_identity
end
save = Thread.current[:__recursive_key__][:inspect]
begin
Thread.current[:__recursive_key__][:inspect] = {}.compare_by_identity
yield
ensure
Thread.current[:__recursive_key__][:inspect] = save
end
end
# Check whether the object_id +id+ is in the current buffer of objects
# to be pretty printed. Used to break cycles in chains of objects to be
# pretty printed.
def check_inspect_key(id)
Thread.current[:__recursive_key__] &&
Thread.current[:__recursive_key__][:inspect] &&
Thread.current[:__recursive_key__][:inspect].include?(id)
end
# Adds the object_id +id+ to the set of objects being pretty printed, so
# as to not repeat objects.
def push_inspect_key(id)
Thread.current[:__recursive_key__][:inspect][id] = true
end
# Removes an object from the set of objects being pretty printed.
def pop_inspect_key(id)
Thread.current[:__recursive_key__][:inspect].delete id
end
# Adds +obj+ to the pretty printing buffer
# using Object#pretty_print or Object#pretty_print_cycle.
#
# Object#pretty_print_cycle is used when +obj+ is already
# printed, a.k.a the object reference chain has a cycle.
def pp(obj = undefined)
# Opal: consider JS-native variables:
%x{
if (obj === null) {
#{text "null"}
#{return}
}
else if (obj === undefined) {
#{text "undefined"}
#{return}
}
else if (obj.$$class === undefined) {
#{text `Object.prototype.toString.apply(obj)`}
#{return}
}
}
# If obj is a Delegator then use the object being delegated to for cycle
# detection
obj = obj.__getobj__ if defined?(::Delegator) and obj.is_a?(::Delegator)
if check_inspect_key(obj)
group {obj.pretty_print_cycle self}
return
end
begin
push_inspect_key(obj)
group {obj.pretty_print self}
ensure
pop_inspect_key(obj) unless PP.sharing_detection
end
end
# A convenience method which is same as follows:
#
# group(1, '#<' + obj.class.name, '>') { ... }
def object_group(obj, &block) # :yield:
group(1, '#<' + obj.class.name, '>', &block)
end
# A convenience method, like object_group, but also reformats the Object's
# object_id.
def object_address_group(obj, &block)
str = Kernel.instance_method(:to_s).bind_call(obj)
str = str.chomp('>')
group(1, str, '>', &block)
end
# A convenience method which is same as follows:
#
# text ','
# breakable
def comma_breakable
text ','
breakable
end
# Adds a separated list.
# The list is separated by comma with breakable space, by default.
#
# #seplist iterates the +list+ using +iter_method+.
# It yields each object to the block given for #seplist.
# The procedure +separator_proc+ is called between each yields.
#
# If the iteration is zero times, +separator_proc+ is not called at all.
#
# If +separator_proc+ is nil or not given,
# +lambda { comma_breakable }+ is used.
# If +iter_method+ is not given, :each is used.
#
# For example, following 3 code fragments has similar effect.
#
# q.seplist([1,2,3]) {|v| xxx v }
#
# q.seplist([1,2,3], lambda { q.comma_breakable }, :each) {|v| xxx v }
#
# xxx 1
# q.comma_breakable
# xxx 2
# q.comma_breakable
# xxx 3
def seplist(list, sep=nil, iter_method=:each) # :yield: element
sep ||= lambda { comma_breakable }
first = true
list.__send__(iter_method) {|*v|
if first
first = false
else
sep.call
end
yield(*v)
}
end
# A present standard failsafe for pretty printing any given Object
def pp_object(obj)
object_address_group(obj) {
seplist(obj.pretty_print_instance_variables, lambda { text ',' }) {|v|
breakable
v = v.to_s if Symbol === v
text v
text '='
group(1) {
breakable ''
pp(obj.instance_eval(v))
}
}
}
end
# A pretty print for a Hash
def pp_hash(obj)
group(1, '{', '}') {
seplist(obj, nil, :each_pair) {|k, v|
group {
pp k
text '=>'
group(1) {
breakable ''
pp v
}
}
}
}
end
end
include PPMethods
class SingleLine < PrettyPrint::SingleLine # :nodoc:
include PPMethods
end
module ObjectMixin # :nodoc:
# 1. specific pretty_print
# 2. specific inspect
# 3. generic pretty_print
# A default pretty printing method for general objects.
# It calls #pretty_print_instance_variables to list instance variables.
#
# If +self+ has a customized (redefined) #inspect method,
# the result of self.inspect is used but it obviously has no
# line break hints.
#
# This module provides predefined #pretty_print methods for some of
# the most commonly used built-in classes for convenience.
def pretty_print(q)
umethod_method = Object.instance_method(:method)
begin
inspect_method = umethod_method.bind_call(self, :inspect)
rescue NameError
end
if inspect_method && inspect_method.owner != Kernel
q.text self.inspect
elsif !inspect_method && self.respond_to?(:inspect)
q.text self.inspect
else
q.pp_object(self)
end
end
# A default pretty printing method for general objects that are
# detected as part of a cycle.
def pretty_print_cycle(q)
q.object_address_group(self) {
q.breakable
q.text '...'
}
end
# Returns a sorted array of instance variable names.
#
# This method should return an array of names of instance variables as symbols or strings as:
# +[:@a, :@b]+.
def pretty_print_instance_variables
instance_variables.sort
end
# Is #inspect implementation using #pretty_print.
# If you implement #pretty_print, it can be used as follows.
#
# alias inspect pretty_print_inspect
#
# However, doing this requires that every class that #inspect is called on
# implement #pretty_print, or a RuntimeError will be raised.
def pretty_print_inspect
if Object.instance_method(:method).bind_call(self, :pretty_print).owner == PP::ObjectMixin
raise "pretty_print is not overridden for #{self.class}"
end
PP.singleline_pp(self, ''.dup)
end
end
end
class Array # :nodoc:
def pretty_print(q) # :nodoc:
q.group(1, '[', ']') {
q.seplist(self) {|v|
q.pp v
}
}
end
def pretty_print_cycle(q) # :nodoc:
q.text(empty? ? '[]' : '[...]')
end
end
class Hash # :nodoc:
def pretty_print(q) # :nodoc:
q.pp_hash self
end
def pretty_print_cycle(q) # :nodoc:
q.text(empty? ? '{}' : '{...}')
end
end
class << ENV # :nodoc:
def pretty_print(q) # :nodoc:
h = {}
ENV.keys.sort.each {|k|
h[k] = ENV[k]
}
q.pp_hash h
end
end
class Struct # :nodoc:
def pretty_print(q) # :nodoc:
q.group(1, sprintf("#<struct %s", PP.mcall(self, Kernel, :class).name), '>') {
q.seplist(PP.mcall(self, Struct, :members), lambda { q.text "," }) {|member|
q.breakable
q.text member.to_s
q.text '='
q.group(1) {
q.breakable ''
q.pp self[member]
}
}
}
end
def pretty_print_cycle(q) # :nodoc:
q.text sprintf("#<struct %s:...>", PP.mcall(self, Kernel, :class).name)
end
end
class Range # :nodoc:
def pretty_print(q) # :nodoc:
q.pp self.begin
q.breakable ''
q.text(self.exclude_end? ? '...' : '..')
q.breakable ''
q.pp self.end if self.end
end
end
class String # :nodoc:
def pretty_print(q) # :nodoc:
lines = self.lines
if lines.size > 1
q.group(0, '', '') do
q.seplist(lines, lambda { q.text ' +'; q.breakable }) do |v|
q.pp v
end
end
else
q.text inspect
end
end
end
# Opal: does not have File::Stat
#class File < IO # :nodoc:
# class Stat # :nodoc:
# def pretty_print(q) # :nodoc:
# require 'etc.so'
# q.object_group(self) {
# q.breakable
# q.text sprintf("dev=0x%x", self.dev); q.comma_breakable
# q.text "ino="; q.pp self.ino; q.comma_breakable
# q.group {
# m = self.mode
# q.text sprintf("mode=0%o", m)
# q.breakable
# q.text sprintf("(%s %c%c%c%c%c%c%c%c%c)",
# self.ftype,
# (m & 0400 == 0 ? ?- : ?r),
# (m & 0200 == 0 ? ?- : ?w),
# (m & 0100 == 0 ? (m & 04000 == 0 ? ?- : ?S) :
# (m & 04000 == 0 ? ?x : ?s)),
# (m & 0040 == 0 ? ?- : ?r),
# (m & 0020 == 0 ? ?- : ?w),
# (m & 0010 == 0 ? (m & 02000 == 0 ? ?- : ?S) :
# (m & 02000 == 0 ? ?x : ?s)),
# (m & 0004 == 0 ? ?- : ?r),
# (m & 0002 == 0 ? ?- : ?w),
# (m & 0001 == 0 ? (m & 01000 == 0 ? ?- : ?T) :
# (m & 01000 == 0 ? ?x : ?t)))
# }
# q.comma_breakable
# q.text "nlink="; q.pp self.nlink; q.comma_breakable
# q.group {
# q.text "uid="; q.pp self.uid
# begin
# pw = Etc.getpwuid(self.uid)
# rescue ArgumentError
# end
# if pw
# q.breakable; q.text "(#{pw.name})"
# end
# }
# q.comma_breakable
# q.group {
# q.text "gid="; q.pp self.gid
# begin
# gr = Etc.getgrgid(self.gid)
# rescue ArgumentError
# end
# if gr
# q.breakable; q.text "(#{gr.name})"
# end
# }
# q.comma_breakable
# q.group {
# q.text sprintf("rdev=0x%x", self.rdev)
# if self.rdev_major && self.rdev_minor
# q.breakable
# q.text sprintf('(%d, %d)', self.rdev_major, self.rdev_minor)
# end
# }
# q.comma_breakable
# q.text "size="; q.pp self.size; q.comma_breakable
# q.text "blksize="; q.pp self.blksize; q.comma_breakable
# q.text "blocks="; q.pp self.blocks; q.comma_breakable
# q.group {
# t = self.atime
# q.text "atime="; q.pp t
# q.breakable; q.text "(#{t.tv_sec})"
# }
# q.comma_breakable
# q.group {
# t = self.mtime
# q.text "mtime="; q.pp t
# q.breakable; q.text "(#{t.tv_sec})"
# }
# q.comma_breakable
# q.group {
# t = self.ctime
# q.text "ctime="; q.pp t
# q.breakable; q.text "(#{t.tv_sec})"
# }
# }
# end
# end
#end
class MatchData # :nodoc:
def pretty_print(q) # :nodoc:
nc = []
self.regexp.named_captures.each {|name, indexes|
indexes.each {|i| nc[i] = name }
}
q.object_group(self) {
q.breakable
q.seplist(0...self.size, lambda { q.breakable }) {|i|
if i == 0
q.pp self[i]
else
if nc[i]
q.text nc[i]
else
q.pp i
end
q.text ':'
q.pp self[i]
end
}
}
end
end
# Opal: does not have RubyVM
#class RubyVM::AbstractSyntaxTree::Node
# def pretty_print_children(q, names = [])
# children.zip(names) do |c, n|
# if n
# q.breakable
# q.text "#{n}:"
# end
# q.group(2) do
# q.breakable
# q.pp c
# end
# end
# end
#
# def pretty_print(q)
# q.group(1, "(#{type}@#{first_lineno}:#{first_column}-#{last_lineno}:#{last_column}", ")") {
# case type
# when :SCOPE
# pretty_print_children(q, %w"tbl args body")
# when :ARGS
# pretty_print_children(q, %w[pre_num pre_init opt first_post post_num post_init rest kw kwrest block])
# when :DEFN
# pretty_print_children(q, %w[mid body])
# when :ARYPTN
# pretty_print_children(q, %w[const pre rest post])
# when :HSHPTN
# pretty_print_children(q, %w[const kw kwrest])
# else
# pretty_print_children(q)
# end
# }
# end
#end
class Object < BasicObject # :nodoc:
include PP::ObjectMixin
end
[Numeric, Symbol, FalseClass, TrueClass, NilClass, Module].each {|c|
c.class_eval {
def pretty_print_cycle(q)
q.text inspect
end
}
}
[Numeric, FalseClass, TrueClass, Module].each {|c|
c.class_eval {
def pretty_print(q)
q.text inspect
end
}
}
module Kernel
# Returns a pretty printed object as a string.
#
# In order to use this method you must first require the PP module:
#
# require 'pp'
#
# See the PP module for more information.
def pretty_inspect
PP.pp(self, StringIO.new).string
end
# prints arguments in pretty form.
#
# pp returns argument(s).
def pp(*objs)
objs.each {|obj|
PP.pp(obj)
}
objs.size <= 1 ? objs.first : objs
end
module_function :pp
end