Import RubyGems trunk revision 1493.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@13862 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/rubygems/commands/pristine_command.rb

@@ -0,0 +1,133 @@
+require 'fileutils'
+require 'rubygems/command'
+require 'rubygems/format'
+require 'rubygems/installer'
+require 'rubygems/version_option'
+
+class Gem::Commands::PristineCommand < Gem::Command
+
+  include Gem::VersionOption
+
+  def initialize
+    super 'pristine',
+          'Restores installed gems to pristine condition from files located in the gem cache',
+          :version => Gem::Requirement.default
+
+    add_option('--all',
+               'Restore all installed gems to pristine',
+               'condition') do |value, options|
+      options[:all] = value
+    end
+
+    add_version_option('restore to', 'pristine condition')
+  end
+
+  def arguments # :nodoc:
+    "GEMNAME       gem to restore to pristine condition (unless --all)"
+  end
+
+  def defaults_str # :nodoc:
+    "--all"
+  end
+
+  def description # :nodoc:
+    <<-EOF
+The pristine command compares the installed gems with the contents of the
+cached gem and restores any files that don't match the cached gem's copy.
+
+If you have made modifications to your installed gems, the pristine command
+will revert them.  After all the gem's files have been checked all bin stubs
+for the gem are regenerated.
+
+If the cached gem cannot be found, you will need to use `gem install` to
+revert the gem.
+    EOF
+  end
+
+  def usage # :nodoc:
+    "#{program_name} [args]"
+  end
+
+  def execute
+    gem_name = nil
+
+    specs = if options[:all] then
+              Gem::SourceIndex.from_installed_gems.map do |name, spec|
+                spec
+              end
+            else
+              gem_name = get_one_gem_name
+              Gem::SourceIndex.from_installed_gems.search(gem_name,
+                                                          options[:version])
+            end
+
+    if specs.empty? then
+      raise Gem::Exception,
+            "Failed to find gem #{gem_name} #{options[:version]}"
+    end
+
+    install_dir = Gem.dir # TODO use installer option
+
+    raise Gem::FilePermissionError.new(install_dir) unless
+      File.writable?(install_dir)
+
+    say "Restoring gem(s) to pristine condition..."
+
+    specs.each do |spec|
+      gem = Dir[File.join(Gem.dir, 'cache', "#{spec.full_name}.gem")].first
+
+      if gem.nil? then
+        alert_error "Cached gem for #{spec.full_name} not found, use `gem install` to restore"
+        next
+      end
+
+      # TODO use installer options
+      installer = Gem::Installer.new gem, :wrappers => true
+
+      gem_file = File.join install_dir, "cache", "#{spec.full_name}.gem"
+
+      security_policy = nil # TODO use installer option
+
+      format = Gem::Format.from_file_by_path gem_file, security_policy
+
+      target_directory = File.join(install_dir, "gems", format.spec.full_name)
+      target_directory.untaint
+
+      pristine_files = format.file_entries.collect { |data| data[0]["path"] }
+      file_map = {}
+
+      format.file_entries.each do |entry, file_data|
+        file_map[entry["path"]] = file_data
+      end
+
+      Dir.chdir target_directory do
+        deployed_files = Dir.glob(File.join("**", "*")) +
+                         Dir.glob(File.join("**", ".*"))
+
+        pristine_files = pristine_files.map { |f| File.expand_path f }
+        deployed_files = deployed_files.map { |f| File.expand_path f }
+
+        to_redeploy = (pristine_files - deployed_files)
+        to_redeploy = to_redeploy.map { |path| path.untaint}
+
+        if to_redeploy.length > 0 then
+          say "Restoring #{to_redeploy.length} file#{to_redeploy.length == 1 ? "" : "s"} to #{spec.full_name}..."
+
+          to_redeploy.each do |path|
+            say "  #{path}"
+            FileUtils.mkdir_p File.dirname(path)
+            File.open(path, "wb") do |out|
+              out.write file_map[path]
+            end
+          end
+        else
+          say "#{spec.full_name} is in pristine condition"
+        end
+      end
+
+      installer.generate_bin
+    end
+  end
+
+end
+