module Gem::Util

def self.correct_for_windows_path(path)
  if path[0].chr == '/' && path[1].chr =~ /[a-z]/i && path[2].chr == ':'
    path[1..-1]
  else
    path
  end
end

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

def self.gunzip(data)
  require 'zlib'
  require 'stringio'
  data = StringIO.new(data, 'r')
  gzip_reader = begin
                  Zlib::GzipReader.new(data)
                rescue Zlib::GzipFile::Error => e
                  raise e.class, e.inspect, e.backtrace
                end
  unzipped = gzip_reader.read
  unzipped.force_encoding Encoding::BINARY
  unzipped
end

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

def self.inflate(data)
  require 'zlib'
  Zlib::Inflate.inflate data
end

def self.popen(*command)
  IO.popen command, &:read
end

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
  system(*(cmds << opt))
end

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