gem_prelude.rb

   1 # depends on: array.rb dir.rb env.rb file.rb hash.rb module.rb regexp.rb
   2
   3 # empty gem_prelude.rb
   4 #
   5 # p Gem::Enable
   6
   7 if defined?(Gem::Enable) && Gem::Enable then
   8
   9   module Kernel
  10
  11     def gem(gem_name, *version_requirements)
  12       Gem.push_gem_version_on_load_path(gem_name, *version_requirements)
  13     end
  14
  15   end
  16
  17   module Gem
  18
  19     ConfigMap = {
  20       :sitedir => RbConfig::CONFIG["sitedir"],
  21       :ruby_version => RbConfig::CONFIG["ruby_version"],
  22       :libdir => RbConfig::CONFIG["libdir"],
  23       :sitelibdir => RbConfig::CONFIG["sitelibdir"],
  24       :arch => RbConfig::CONFIG["arch"],
  25       :bindir => RbConfig::CONFIG["bindir"],
  26       :EXEEXT => RbConfig::CONFIG["EXEEXT"],
  27       :RUBY_SO_NAME => RbConfig::CONFIG["RUBY_SO_NAME"],
  28       :ruby_install_name => RbConfig::CONFIG["ruby_install_name"]
  29     }
  30
  31     class << self
  32
  33       def default_dir
  34         if defined? RUBY_FRAMEWORK_VERSION
  35           return File.join(File.dirname(ConfigMap[:sitedir]), "Gems")
  36         else
  37           File.join(ConfigMap[:libdir], 'ruby', 'gems', ConfigMap[:ruby_version])
  38         end
  39       end
  40
  41       def dir
  42         @gem_home ||= nil
  43         set_home(ENV['GEM_HOME'] || default_dir) unless @gem_home
  44         @gem_home
  45       end
  46
  47       def path
  48         @gem_path ||= nil
  49         unless @gem_path
  50           paths = [ENV['GEM_PATH']]
  51           paths << APPLE_GEM_HOME if defined? APPLE_GEM_HOME
  52           set_paths(paths.compact.join(File::PATH_SEPARATOR))
  53         end
  54         @gem_path
  55       end
  56
  57       # Set the Gem home directory (as reported by +dir+).
  58       def set_home(home)
  59         @gem_home = home
  60         ensure_gem_subdirectories(@gem_home)
  61       end
  62
  63       def set_paths(gpaths)
  64         if gpaths
  65           @gem_path = gpaths.split(File::PATH_SEPARATOR)
  66           @gem_path << Gem.dir
  67         else
  68           @gem_path = [Gem.dir]
  69         end
  70         @gem_path.uniq!
  71         @gem_path.each do |gp| ensure_gem_subdirectories(gp) end
  72       end
  73
  74       def ensure_gem_subdirectories(path)
  75       end
  76
  77     end
  78
  79     module QuickLoader
  80
  81       class << self
  82         def load_full_rubygems_library
  83           class << Gem
  84             Gem.methods(false).each do |method_name|
  85               undef_method method_name
  86             end
  87           end
  88
  89           Kernel.send :undef_method, :gem
  90
  91           $".delete File.join(Gem::ConfigMap[:libdir], 'ruby',
  92                               Gem::ConfigMap[:ruby_version], 'rubygems.rb')
  93
  94           require 'rubygems'
  95         end
  96       end
  97
  98       GemPaths = {}
  99       GemVersions = {}
 100
 101       def push_gem_version_on_load_path(gem_name, *version_requirements)
 102         if version_requirements.empty?
 103           unless GemPaths.has_key?(gem_name)
 104             raise LoadError.new("Could not find RubyGem #{gem_name} (>= 0)\n")
 105           end
 106
 107           # highest version gems already active
 108           return false
 109         else
 110           if version_requirements.length > 1
 111             QuickLoader.load_full_rubygems_library
 112             return gem(gem_name, *version_requirements)
 113           end
 114
 115           requirement, version = version_requirements[0].split
 116           requirement.strip!
 117
 118           if requirement == ">" || requirement == ">="
 119             if (GemVersions[gem_name] <=> Gem.calculate_integers_for_gem_version(version)) >= 0
 120               return false
 121             end
 122           elsif requirement == "~>"
 123             loaded_version = GemVersions[gem_name]
 124             required_version = Gem.calculate_integers_for_gem_version(version)
 125             if loaded_version && (loaded_version[0] == required_version[0])
 126               return false
 127             end
 128           end
 129
 130           QuickLoader.load_full_rubygems_library
 131           gem(gem_name, *version_requirements)
 132         end
 133       end
 134
 135       def calculate_integers_for_gem_version(gem_version)
 136         numbers = gem_version.split(".").collect {|n| n.to_i}
 137         numbers.pop while numbers.last == 0
 138         numbers << 0 if numbers.empty?
 139         numbers
 140       end
 141
 142       def push_all_highest_version_gems_on_load_path
 143         Gem.path.each do |path|
 144           gems_directory = File.join(path, "gems")
 145           if File.exist?(gems_directory)
 146             Dir.entries(gems_directory).each do |gem_directory_name|
 147               next if gem_directory_name == "." || gem_directory_name == ".."
 148               dash = gem_directory_name.rindex("-")
 149               next if dash.nil?
 150               gem_name = gem_directory_name[0...dash]
 151               current_version = GemVersions[gem_name]
 152               new_version = calculate_integers_for_gem_version(gem_directory_name[dash+1..-1])
 153               if current_version
 154                 if (current_version <=> new_version) == -1
 155                   GemVersions[gem_name] = new_version
 156                   GemPaths[gem_name] = File.join(gems_directory, gem_directory_name)
 157                 end
 158               else
 159                 GemVersions[gem_name] = new_version
 160                 GemPaths[gem_name] = File.join(gems_directory, gem_directory_name)
 161               end
 162             end
 163           end
 164         end
 165
 166         require_paths = []
 167
 168         GemPaths.values.each do |path|
 169           if File.exist?(File.join(path, ".require_paths"))
 170             require_paths.concat(File.read(File.join(path, ".require_paths")).split.map {|require_path| File.join(path, require_path)})
 171           else
 172             require_paths << File.join(path, "bin") if File.exist?(File.join(path, "bin"))
 173             require_paths << File.join(path, "lib") if File.exist?(File.join(path, "lib"))
 174           end
 175         end
 176
 177         # "tag" the first require_path inserted into the $LOAD_PATH to enable
 178         # indexing correctly with rubygems proper when it inserts an explicitly
 179         # gem version
 180         unless require_paths.empty?
 181           require_paths.first.instance_variable_set(:@gem_prelude_index, true)
 182         end
 183         # gem directories must come after -I and ENV['RUBYLIB']
 184         $:[$:.index(ConfigMap[:sitelibdir]),0] = require_paths
 185       end
 186
 187       def const_missing(constant)
 188         QuickLoader.load_full_rubygems_library
 189         Gem.const_get(constant)
 190       end
 191
 192       def method_missing(method, *args, &block)
 193         QuickLoader.load_full_rubygems_library
 194         super unless Gem.respond_to?(method)
 195         Gem.send(method, *args, &block)
 196       end
 197     end
 198
 199     extend QuickLoader
 200
 201   end
 202
 203   begin
 204     Gem.push_all_highest_version_gems_on_load_path
 205     $" << File.join(Gem::ConfigMap[:libdir], "ruby",
 206                     Gem::ConfigMap[:ruby_version], "rubygems.rb")
 207   rescue Exception => e
 208     puts "Error loading gem paths on load path in gem_prelude"
 209     puts e
 210     puts e.backtrace.join("\n")
 211   end
 212
 213 end
 214