Turn json_pure into an empty gem

Fix: ruby#650
Closes: ruby#682

Gemfile

@@ -1,10 +1,6 @@
 source 'https://rubygems.org'
 
-if ENV['JSON'] == 'pure'
-  gemspec name: 'json_pure'
-else
-  gemspec name: 'json'
-end
+gemspec name: 'json'
 
 group :development do
   gem "ruby_memcheck" if RUBY_PLATFORM =~ /linux/i

README.md

@@ -5,16 +5,10 @@
 ## Description
 
 This is an implementation of the JSON specification according to RFC 7159
-http://www.ietf.org/rfc/rfc7159.txt . There is two variants available:
+http://www.ietf.org/rfc/rfc7159.txt .
 
-* A pure ruby variant, that relies on the `strscan` extensions, which is
-  part of the ruby standard library.
-* The quite a bit faster native extension variant, which is in parts
-  implemented in C or Java and comes with a parser generated by the [Ragel]
-  state machine compiler.
-
-Both variants of the JSON generator generate UTF-8 character sequences by
-default. If an :ascii\_only option with a true value is given, they escape all
+The JSON generator generate UTF-8 character sequences by default.
+If an :ascii\_only option with a true value is given, they escape all
 non-ASCII and control characters with \uXXXX escape sequences, and support
 UTF-16 surrogate pairs in order to be able to generate the whole range of
 unicode code points.

Rakefile

@@ -56,12 +56,8 @@ else
   RAGEL_DOTGEN      = %w[rlgen-dot rlgen-cd ragel].find(&which)
 end
 
-desc "Installing library (pure)"
-task :install_pure do
-  ruby 'install.rb'
-end
-
-task :install_ext_really do
+desc "Installing library (extension)"
+task :install => [ :compile ] do
   sitearchdir = CONFIG["sitearchdir"]
   cd 'ext' do
     for file in Dir["json/ext/*.#{CONFIG['DLEXT']}"]
@@ -73,30 +69,6 @@ task :install_ext_really do
   end
 end
 
-desc "Installing library (extension)"
-task :install_ext => [ :compile, :install_pure, :install_ext_really ]
-
-desc "Installing library (extension)"
-task :install => :install_ext
-
-task :check_env do
-  ENV.key?('JSON') or fail "JSON env var is required"
-end
-
-desc "Testing library (pure ruby)"
-task :test_pure => [ :set_env_pure, :check_env, :do_test_pure ]
-task(:set_env_pure) { ENV['JSON'] = 'pure' }
-
-UndocumentedTestTask.new do |t|
-  t.name = 'do_test_pure'
-  t.test_files = FileList['test/json/*_test.rb']
-  t.verbose = true
-  t.options = '-v'
-end
-
-desc "Testing library (pure ruby and extension)"
-task :test => [ :test_pure, :test_ext ]
-
 namespace :gems do
   desc 'Install all development gems'
   task :install do
@@ -177,16 +149,14 @@ if defined?(RUBY_ENGINE) and RUBY_ENGINE == 'jruby'
     sh "gem build -o pkg/json-#{PKG_VERSION}-java.gem json.gemspec"
   end
 
-  desc "Testing library (jruby)"
-  task :test_ext => [ :set_env_ext, :create_jar, :check_env, :do_test_ext ]
-  task(:set_env_ext) { ENV['JSON'] = 'ext' }
-
   UndocumentedTestTask.new do |t|
-    t.name = 'do_test_ext'
+    t.name = :test
     t.test_files = FileList['test/json/*_test.rb']
     t.verbose = true
     t.options = '-v'
   end
+  desc "Testing library (jruby)"
+  task :test => [:create_jar ]
 
   file JRUBY_PARSER_JAR => :compile do
     cd 'java/src' do
@@ -239,20 +209,19 @@ else
     task :compile => [ :ragel, EXT_PARSER_DL, EXT_GENERATOR_DL ]
   end
 
-  desc "Testing library (extension)"
-  task :test_ext => [ :set_env_ext, :check_env, :compile, :do_test_ext ]
-  task(:set_env_ext) { ENV['JSON'] = 'ext' }
-
   UndocumentedTestTask.new do |t|
-    t.name = 'do_test_ext'
+    t.name = :test
     t.test_files = FileList['test/json/*_test.rb']
     t.verbose = true
     t.options = '-v'
   end
 
+  desc "Testing library (extension)"
+  task :test => [ :compile ]
+
   begin
     require "ruby_memcheck"
-    RubyMemcheck::TestTask.new(valgrind: [ :set_env_ext, :check_env, :compile, :do_test_ext ]) do |t|
+    RubyMemcheck::TestTask.new(valgrind: [ :compile, :test ]) do |t|
       t.test_files = FileList['test/json/*_test.rb']
       t.verbose = true
       t.options = '-v'

json_pure.gemspec

@@ -23,28 +23,7 @@ Gem::Specification.new do |s|
     "LEGAL",
     "README.md",
     "json_pure.gemspec",
-    "lib/json.rb",
-    "lib/json/add/bigdecimal.rb",
-    "lib/json/add/complex.rb",
-    "lib/json/add/core.rb",
-    "lib/json/add/date.rb",
-    "lib/json/add/date_time.rb",
-    "lib/json/add/exception.rb",
-    "lib/json/add/ostruct.rb",
-    "lib/json/add/range.rb",
-    "lib/json/add/rational.rb",
-    "lib/json/add/regexp.rb",
-    "lib/json/add/set.rb",
-    "lib/json/add/struct.rb",
-    "lib/json/add/symbol.rb",
-    "lib/json/add/time.rb",
-    "lib/json/common.rb",
-    "lib/json/ext.rb",
-    "lib/json/generic_object.rb",
     "lib/json/pure.rb",
-    "lib/json/pure/generator.rb",
-    "lib/json/pure/parser.rb",
-    "lib/json/version.rb",
   ]
   s.homepage = "https://ruby.github.io/json"
   s.metadata = {
@@ -56,5 +35,7 @@ Gem::Specification.new do |s|
     'wiki_uri'          => 'https://github.com/ruby/json/wiki'
   }
 
+  s.add_dependency "json"
+
   s.required_ruby_version = Gem::Requirement.new(">= 2.7")
 end

lib/json.rb

@@ -583,10 +583,5 @@
 #
 module JSON
   require 'json/version'
-
-  begin
-    require 'json/ext'
-  rescue LoadError
-    require 'json/pure'
-  end
+  require 'json/ext'
 end

lib/json/common.rb

@@ -32,9 +32,7 @@ def [](object, opts = {})
       JSON.generate(object, opts)
     end
 
-    # Returns the JSON parser class that is used by JSON. This is either
-    # JSON::Ext::Parser or JSON::Pure::Parser:
-    #   JSON.parser # => JSON::Ext::Parser
+    # Returns the JSON parser class that is used by JSON.
     attr_reader :parser
 
     # Set the JSON parser class _parser_ to be used by JSON.
@@ -97,14 +95,10 @@ def create_pretty_state
       )
     end
 
-    # Returns the JSON generator module that is used by JSON. This is
-    # either JSON::Ext::Generator or JSON::Pure::Generator:
-    #   JSON.generator # => JSON::Ext::Generator
+    # Returns the JSON generator module that is used by JSON.
     attr_reader :generator
 
-    # Sets or Returns the JSON generator state class that is used by JSON. This is
-    # either JSON::Ext::Generator::State or JSON::Pure::Generator::State:
-    #   JSON.state # => JSON::Ext::Generator::State
+    # Sets or Returns the JSON generator state class that is used by JSON.
     attr_accessor :state
   end
 

lib/json/ext.rb

@@ -8,14 +8,12 @@ module JSON
   module Ext
     if RUBY_ENGINE == 'truffleruby'
       require 'json/ext/parser'
-      require 'json/pure'
-      $DEBUG and warn "Using Ext extension for JSON parser and Pure library for JSON generator."
+      require 'json/truffle_ruby/generator'
       JSON.parser = Parser
-      JSON.generator = JSON::Pure::Generator
+      JSON.generator = ::JSON::TruffleRuby::Generator
     else
       require 'json/ext/parser'
       require 'json/ext/generator'
-      $DEBUG and warn "Using Ext extension for JSON."
       JSON.parser = Parser
       JSON.generator = Generator
     end

lib/json/pure.rb

@@ -1,16 +1,4 @@
 # frozen_string_literal: true
-require 'json/common'
 
-module JSON
-  # This module holds all the modules/classes that implement JSON's
-  # functionality in pure ruby.
-  module Pure
-    require 'json/pure/parser'
-    require 'json/pure/generator'
-    $DEBUG and warn "Using Pure library for JSON."
-    JSON.parser = Parser
-    JSON.generator = Generator
-  end
-
-  JSON_LOADED = true unless defined?(::JSON::JSON_LOADED)
-end
+warn "`json_pure` is deprecated and has no effect, just use `json`"
+require "json"