# module Gem::Util

This module contains various utility methods as module methods.

### Public Class Methods

glob_files_in_dir(glob, base_path) click to toggle source

Globs for files matching `pattern` inside of `directory`, returning absolute paths to the matching files.

    # File lib/rubygems/util.rb, line 123
    def self.glob_files_in_dir(glob, base_path)
      if RUBY_VERSION >= "2.5"
        Dir.glob(glob, base: base_path).map! {|f| File.expand_path(f, base_path) }
      else
        Dir.glob(File.expand_path(glob, base_path))
      end
    end

gunzip(data) click to toggle source

`Zlib::GzipReader` wrapper that unzips `data`.

    # File lib/rubygems/util.rb, line 12
    def self.gunzip(data)
      require 'zlib'
      require 'stringio'
      data = StringIO.new(data, 'r')

      unzipped = Zlib::GzipReader.new(data).read
      unzipped.force_encoding Encoding::BINARY
      unzipped
    end

gzip(data) click to toggle source

`Zlib::GzipWriter` wrapper that zips `data`.

    # File lib/rubygems/util.rb, line 25
    def self.gzip(data)
      require 'zlib'
      require 'stringio'
      zipped = StringIO.new(String.new, 'w')
      zipped.set_encoding Encoding::BINARY

      Zlib::GzipWriter.wrap zipped do |io| io.write data end

      zipped.string
    end

inflate(data) click to toggle source

A `Zlib::Inflate#inflate` wrapper

    # File lib/rubygems/util.rb, line 39
    def self.inflate(data)
      require 'zlib'
      Zlib::Inflate.inflate data
    end

popen(*command) click to toggle source

This calls `IO.popen` where it accepts an array for a `command` (Ruby 1.9+) and implements an `IO.popen`-like behavior where it does not accept an array for a command.

    # File lib/rubygems/util.rb, line 49
    def self.popen(*command)
      IO.popen command, &:read
    rescue TypeError # ruby 1.8 only supports string command
      r, w = IO.pipe

      pid = fork do
        STDIN.close
        STDOUT.reopen w

        exec(*command)
      end

      w.close

      begin
        return r.read
      ensure
        Process.wait pid
      end
    end

silent_system(*command) click to toggle source

Invokes system, but silences all output.

    # File lib/rubygems/util.rb, line 73
    def self.silent_system(*command)
      opt = {:out => IO::NULL, :err => [:child, :out]}
      if Hash === command.last
        opt.update(command.last)
        cmds = command[0...-1]
      else
        cmds = command.dup
      end
      return system(*(cmds << opt))
    rescue TypeError
      @silent_mutex ||= Mutex.new

      @silent_mutex.synchronize do
        begin
          stdout = STDOUT.dup
          stderr = STDERR.dup

          STDOUT.reopen IO::NULL, 'w'
          STDERR.reopen IO::NULL, 'w'

          return system(*command)
        ensure
          STDOUT.reopen stdout
          STDERR.reopen stderr
          stdout.close
          stderr.close
        end
      end
    end

traverse_parents(directory, &block) click to toggle source

Enumerates the parents of `directory`.

    # File lib/rubygems/util.rb, line 106
    def self.traverse_parents(directory, &block)
      return enum_for __method__, directory unless block_given?

      here = File.expand_path directory
      loop do
        Dir.chdir here, &block rescue Errno::EACCES

        new_here = File.expand_path('..', here)
        return if new_here == here # toplevel
        here = new_here
      end
    end